Energetics of cultivation: draft animals vs. combustion engines and the Haber process

The energy use by the agricultural sector of the economy has been widely discussed and debated in the peak oil community.  The amount of energy used directly at farms is not very large; typical claims for the fuel required to cover a field with a plow or other implement are in the range of one gallon of diesel per acre per pass.  Assuming seeding, harvesting and 3 other passes per year, the total comes to approximately 750 MJ per acre per year.  Nitrogen fertilizer applied at 200 pounds of nitrogen per acre would account for another 4600 MJ per acre1.  Residues from many crops such as corn can supply over 20 GJ per acre and energy sources such as wood chips and fuel grasses are even more productive.  Farming operations such as dairies have already become net exporters of energy as electricity.  This suggests that even a mechanized farm can be self-sufficient in energy, and "fast crash" doom scenarios involving the collapse of farming are not very likely.

1    Farming before powered machinery

Before self-powered farm machinery, there were draft animals.  They were slow to reproduce and train, and often dangerous to work.  They were fed using the one quarter to one third of land fallowed as pasture at any given time.  Some grain (such as oats) was also needed as supplemental feed.

Despite use of animal manures as fertilizer, the yields of the time were not very high.  40 bushels of corn (maize) per acre were typical.  Combined with fallowed acreage, net productivity was a fraction of today's averages.  Productivity was also low; a double-furrow plow pulled by 3 or 4 horses could only plow 2.5 acres per day.

2    The transition to modern practices: steam tractors

The change to steam gave several major improvements.  Steam engines could use any fuel which would burn in the fire box; it did not have to be suitable for animal food.  They also did not have to be "fed" when not working.  Last, the productivity went up radically; one man on a steam tractor could plow 25 to 40 acres per day.

The thermal efficiency of open-cycle steam engines is quite low, roughly 5%.  Guessing from the efficiency of modern diesel engines, it would have taken perhaps 1.2 GJ of fuel to make one pass over an acre.  This is about 180 pounds of firewood, or a considerably smaller amount of coal.  Being able to plow several acres with the wood from one tree was a huge improvement over draft animals.

3    Internal combustion engines (ICEs) and their efficiency

Internal combustion engines are much more efficient than piston steam engines, as well as much more convenient to operate.  Thermal efficiency of medium-speed diesel engines runs upwards of 40%, and low-speed marine diesels can top 50%.  Internal combustion engines can also operate on biofuels, with handicaps which depend on the exact fuel fed to the engine.

4    Homegrown ICE fuel supplies

While current vehicles and farm equipment are fairly finicky about their fuel, the generic ICE is quite adaptable.  Spark-ignition ICEs can be run on everything from petroleum to ammonia to carbon monoxide made from partial combustion of charcoal.  Diesel engines are somewhat fussier, but they can be "co-fueled" with some amount of liquid used to ignite a charge of air and a high-octane gaseous fuel.  The addition of gaseous fuel to diesel intake air is called fumigation.  Kits are available to fumigate propane into diesels to improve their power and reduce their smoke emissions.

Most current farm equipment has diesel engines.  One of the features of the fast-crash doom scenario is that there will be little or no time to make major adaptations for different fuel supplies, so the most interesting possibilities are those which can be

  • built from common materials and
  • retrofitted to existing engines.
Are there significant possibilities out there?  I believe there are.  Here's a short list off the top of my head:

Straight vegetable oil (SVO).  SVO is one step removed from biodiesel, but requires no methanol or other processing.  It can be used directly after pressing so long as it is filtered so as not to clog pumps and injectors.  SVO must be kept hot to thin it enough to atomize, so engines must be fully warm before using it.  This can be accomplished by heating the fuel and coolant externally, or starting and warming up on petroleum diesel or biodiesel.  The fuel system must be flushed of SVO before the engine is allowed to cool off again.

Supplies of SVO are likely to be limited, but if SVO is used for a "pilot injection" to ignite a charge of another fuel it can be stretched considerably.

Fumigated bio-gas.  Bio-gas can be produced from animal wastes and stored in tanks.  Introducing gas into diesel intake air creates a fuel-air charge which ignites and burns when oil is injected by the conventional fuel system.  It is not usable as the sole fuel in a diesel engine, but it can stretch the supply of liquid fuel.  A dual-fuel biomethane bus in the UK expects biomethane to supply 60-80% of its fuel.  As no biomethane is used when the engine is at idle, agricultural equipment could expect to use a higher fraction of biogas than a bus.

The downside of biogas is that it is a gas, and storage cylinders are heavy and bulky.  Materials likely to be on-hand would leave a a great deal to be desired:  low-pressure cylinders such as propane tanks can contain biogas but would hold relatively little fuel even if it is purified to remove CO2.  A 250-gallon propane "pig" pressurized to 250 PSI would hold the equivalent of about 4 gallons of diesel fuel.  It might be possible to get work done this way, but refueling would be very frequent and take a great deal of time away from work.

Fumigated producer gas.  Gas does not have to be delivered to the vehicle; it can be produced on board from solid or liquid fuels.  The technology for using gasogenes to produce fuel gas for a combustion engine was brought to a high level of refinement during previous periods of oil rationing (such as WWII).  Gasogenes were revisited by the USDA during the 70's oil price shocks, and designs created which could be built out of available materials to power tractors in the event of fuel shortages.

Gasogenes can use most any dry combustible matter as fuel.  Wood chips and charcoal are conventional feedstocks.  Dried grass pellets and torrefied biomass are other possibilities.  Combustible liquids may be used also; a liquid fuel which is not suitable for an engine's fuel system may be turned into a gas for fumigation.

5    Biofuel energy requirements

For the sake of argument, let's start with a sub-optimal energy system.  Dried biomass loses very little of the original energy (though biomass may not remain dry unless it is stored correctly).  Torrefaction retains roughly 90% of the energy of the original biomass in the product.  Pyrolysis oil retains about 70%.  Production of charcoal may yield about 50% in the solid product (the remainder comes off as gas and heat).  Therefore, let's assume the use of charcoal as the fuel product.

Next, let's assume conversion of charcoal to producer gas in a gasogene.  The fuel portion of charcoal is almost entirely carbon.  Carbon has a heat of combustion of 93960 cal/mol, while carbon monoxide has 68560 cal/mol; 73% of the energy of carbon is retained in the gas product of the gasogene, not including any CO2 from the exhaust gas recycled to CO using excess heat.  The hypothetical conversion efficiency from biomass through charcoal to fuel gas in the vehicle is thus 37% (not including any productive use of heat or off-gas created in the production of the charcoal).

If the vehicle is a farm tractor or combine which requires 1 gallon-equivalent of energy per acre per pass, of which 90% is coming from fuel gas produced from charcoal, 5 passes per season requires 1.7 million BTU of biomass.  A further 10% of liquid fuel, or 700 kBTU/ac/year, is needed for pilot ignition; since this is relatively small I'll just count it at volume parity with petroleum diesel.  This comes to 0.5 gallon per acre per year.

6    Biofuel feedstock availability

The amount of available feedstock depends on the productivity of the crop and the fraction which winds up as byproducts, but we can get some estimates.  At a yield of 150 bushels per acre, corn (maize) produces roughly 1.5 dry tons of excess stover (not needed for erosion control) per acre, of which 15-20% (0.22-0.3 tons) is cobs.  At 17.4 million BTU per ton, the actual fuel requirement is less than 0.1 tons of biomass.  Corn would in fact yield a very large excess of biomass energy beyond the needs for farm machinery working the field.

Oil for ignition can also come from corn.  At 0.5 gal/ac/yr, the ignition requirements can be met by the oil from about 2.5 bushels/acre of corn (0.2 gal/bu).  The byproduct of pressing is also usable as food.

Other crops also appear to produce sufficient byproduct biomass.  The yield of wheat straw from winter wheat is over 2 tons per acre.

If the main crop does not yield oil, some small amount of land can be devoted to oilseeds.  Sunflowers or canola will do for this.  At a yield of 77 gallons per acre, one acre of canola would supply ignition fuel to till and harvest 150 acres.  Such a modest amount of oil would be easy to produce locally.

These figures suggest that the energy situation of most farms is not nearly as bad as some paint it.  Even assuming the least-efficient pathway for converting biomass to vehicle fuel (charcoal), farms still appear to generate much more energy as non-food biomass than they need to run machinery.  Machinery has the virtues of not having to be bred up from small initial stocks, requires no animal training and no major changes in farm practices and skills, and certainly is not going to be stolen and eaten.

6    Biofuel energy excess and nitrogen fixation

The amount of excess energy from crop byproducts suggests that they might be exchanged for other necessary farm inputs.  For instance, bio-oil (pyrolysis oil) can be produced from almost any finely-divided dry biomass.  It preserves about 70% of the energy of the biomass, and is a relatively dense liquid which seems fairly easy to handle.  One ton per acre of corn stover would yield about 12.2 million BTU of bio-oil.  If this were used as a natural gas substitute in an ammonia plant, it would suffice to produce roughly 680 pounds of ammonia, containing 560 pounds of nitrogen.  Most nitrogen application rates for corn are under 200 pounds per acre (some recommendations as little as ~50 lb/ac), so corn would be enough to provide a large excess of nitrogen fertilizer also.

This analysis does not look at the energy economy of livestock operations.  Anaerobic digestion of manure from cattle, chickens and swine produces more fuel gas than many of them can use; already many farms have turned into net producers of electricity generated from biogas.  While the excess is small on the scale of society, it does suggest that rural farming areas may be able to keep the lights on without purchasing energy.


Some have suggested that shortages of petroleum could produce a collapse of mechanized farming in the near term, with all that implies.  This scenario does not appear to be realistic.  Known methods appear to be able to keep farm machinery operational using only the energy produced on farms themselves, mostly using food byproducts rather than dedicated fuel crops; this is considerably better than the food requirements of draft animals.  The superiority of machinery over animal power, both for productivity and economy and reliability of energy supply, guarantees that it would continue to be maintained and used for some time even if the "fast crash" scenarios come to pass.


1 Assuming 1150 m³ of natural gas per metric ton ammonia and 37 MJ/m³ natural gas, ammonia requires approximately 43 GJ/tonne, or about 23 MJ per pound of nitrogen.

Solar powered hydroponics anyone?


Grow the plants directly in a container with water in it... Then you don't need a water pump just an air pump to keep a bit of dissolved oxygen in the water. I did it on the balcony this year and grew a 7 foot tomato plant:


As well as many fine bunches of good tasting tomatoes I've also got the hottest damn chillies you have ever tasted (I think they may be scotch bonnets actually) -so this weekend its chilli-con-carne!


Cool! or is it "hot". :-)

I've actually been experimenting a bit with pumps myself because I want to try my hand at combination aquaculture and hydroponics so for that you really need some flowing water. I have a 45W panel hooked up to a 165 amp hour deep cycle marine battery via a charge controller and an off the shelf AC garden pond pump which I'm running off a cheap 400W sine inverter that's also connected to the battery. I'm currently experimenting with different size containers and configurations to get a handle on what might work best.


Good analysis. I believe that in general you are correct. One concern I have is that modern farm equipment manufactured in the last few years has computers to control the engines. The SVO conversions I have seen use older engines with mechanical controls. Will the newer computer controled engines be capable of being retrofitted to alternate fuels?

My opinion on the most likely alternative is the local production of vegetable oil producing crops. Unlike the feed for draft animals the high protein byproduct of oil crushing operations can be used for human of animal feed. This means that instead of 30% loss of productive lands the effective percentage will be much lower.

I would expect that these high-tech engines, with their common-rail electronic fuel injection, would need to be "re-chipped" or otherwise recalibrated to work as bi-fuel systems.  This is something which ought to be prepared and tested beforehand; fortunately, the inventory costs of software are trivial.

Agreed that sunflower seed meal, rolled corn or corn meal, etc. remain suitable for human consumption and only represent a small loss of calories.  However, even assuming the oil production is lost as food, you've got the loss figure much too high.  2.5 bushels out of 150 is 1.7%, and 1 acre out of 150 planted to canola is 0.7%.  These figures are down in the noise of annual variation.

I, for one, have serious doubts that we can sustainably harvest much of the biomass produced on a farm. Assuming virgin land, you might expect a decade or two of production before the loss of nutrients really starts to seriously damp production. There isn't a whole lot of virgin land left.

I've been experimenting with low-input livestock farming. In my operation, the vast majority of nutrients are returned to the soil. Even so, I have to be very careful about how much is grazed and when. Weather plays a big role in how I control where and how much the animals graze. If I screw up (and that's happened) it takes 1-3 years for the pasture to recover. In an energy operation, where most of the above ground nutrients are harvested and shipped off for processing, replacing nutrients would be key.

Given my experiences, and the fact that most of the world's arable land is pretty tired, I worry that we can harvest economically significant amounts of biomass for energy for any length of time. If the inputs to do so were free and had low embodied energy, I'd think differently, but they aren't. Even if they were, the endeavor still seems like like running on a treadmill to get somewhere.

EP has supplied the numbers necessary to prove what I have said here several times over the last few months-there is no reason to think that we must starve at least here in the US and other rich countries due to a collapse of the oil supply because farming and food delivery requires relatively little fuel most or all of which can be biofuels.

The long term use of corn stover and other crop residue is problematic but at least some of the mineral content can be easily recycled by simply scattering the ashes on cropland if it is processed and used on the farm.There would be a window of several years available to work out problems along this line.

The real crunch -the one that might actually likely result in widespread starvation -will hit countries dependent on paying for food imports by exporting stuff the world no longer wants or can afford.

A second crunch might materialize when the existing machinery reaches the end of its service life but heavy duty equipment can be made to run for many many years beyond its normal servive life and it is likely that there will be enough remmant industrial capacity to manufacture as many new trucks and tractors as are necessary.

The thing that scares me is that the biofuel industries become successful enough to convince the public that we can continue to run many tens of millions of cars,power boats,passenger aircraft,etc,on biofuel.

I am utterly convinced that if this happens we will be irrevocably committed to a ride down the environmental high road to hell.

The thing that scares me is that the biofuel industries become successful enough to convince the public that we can continue to run many tens of millions of cars,power boats,passenger aircraft,etc,on biofuel.

Bio-fuel, unlike fossil fuels, can be made to be sustainable - but it will never be able to sustain world BAU growth. Look to see the world's population 100 years ago to see what sustainable organic agriculture can support.

Peak phosphorus seems to be well in the past and will likely affect intensive agriculture more than the inevitable declining liquid fossil fuels - food and water will be some of the last things to get an allocation of fossil energy for most nations.

I have a concern about phosphorous longer term, but recent peaking is not a sign of lacking resources but an indication of better P management. Over applied P not taken up by plants will chemically bind with soil minerals and become relatively unavailable. This bound P can be slowly released by weathering and soil microorganisms.
Soils had a large deficit of P until inorganic P became available, requiring heavy applications in past years. Today it is common to do soil or leaf testing to determine fertilizer application.

Natural soil fertility varies widely, but almost no soils will produce today’s high wields without additional fertilizer, especially N.

Where I live in the southeast US soils are poor and easily depleted. The Cullers Rotation experiment shows what happens over decades with various fertilizer treatments.


Not returning biomass to soil reduces moisture retaining capacity and friability. Cellulose, a primary constituent of plants, is very absorbent.

In Energy at the Crossroads, V. Smil stated that 50% of all biomass is harvested.

The thing that scares me is that the biofuel industries become successful enough to convince the public that we can continue to run many tens of millions of cars,power boats,passenger aircraft,etc,on biofuel.

I am utterly convinced that if this happens we will be irrevocably committed to a ride down the environmental high road to hell.

This is very true.  The NPP of farmland runs far short of what it takes to replace oil, let alone all fossil fuels.  Biofuel from the farm can give us a reprieve, not amnesty.

During the depression people starved.
There was a lot more land and a lot less people and debt then.......
It's all well and good to say "there is no reason to think that we must starve at least here in the US and other rich countries due to a collapse of the oil supply because farming and food delivery requires relatively little fuel most or all of which can be biofuels" but for that to eventuate you must be assuming economic BAU even though we have a "collapse of the oil supply".

If farmers are like any business they need a market. Out of work people have no money to pay for food. That is where the system will break down. Write your own scenario after you come to grips with that reality. If transport is plentiful and even free it won't make an iota of difference if the product can't be sold profitably.

Perhaps I should have added ,assuming the present status quo of state local and federal government lasts or something to that effect-My assumption is that so long as we still have the vote and television, we will have a welfare net that will prevent outright starvation on a large scale in this country and other wealthy countries if it is still possible to grow or buy food.

If the government fails, people will starve.

How many is anybody's guess-I could easily afford to feed a couple of unpaid extra hands in such a situatuion but where would I get MONEY to pay them ?

People with money would once again find themselves able to afford servants but unable to afford cars.

A relevant article here Researchers study ground cover to reduce impact of biomass harvest Though I agree that even just 1/4 ton/acre erosion loss is not sustainable long-term, still Engineer-Poet proves that for agricultural purposes, nowhere near the 75% stover harvest proposed is required, and certainly in all the scenarios he proposes, the final ash remaining will still contain most mineral nutrients required by the following crops. That removed by the primary food crop of course will still need to be recovered and returned, a job for advanced municipal waste treatment facilities.

..the final ash remaining will still contain most mineral nutrients required by the following crops.

There's more to soil structure & fertility than mineral nutrient content. Stover and other crop residues decay into refractile humic & fulvic substances with half lives on the order of centuries. These substances hold water, serve as substrate for beneficial microorganisms & give texture & structure to soils. Removing biomass from soils to be processed & burnt for fuel deprives soils of vital organic content, even if ash is returned to the fields.

I'm sorry but I find this analysis little more than another food for fuel, greener version of BAU type, exercise in hopeful visionary fantasizing of a better tomorrow. The reality is apt to be considerably different.

I did say explicitly "nowhere near the 75% stover harvest proposed is required". You need to lighten up some, you'll work yourself into a full-on depression way before the economy. No use in that.


You are right-the problems created by farming as we farm today are bad enough and are gradually getting worse-but most people,including most farmers, can't see the truth of this assertion because the process,in terms of monkey time, is too slow but that's the way our mental clocks are calibrated.Or as somebody else put it,we the frogs in the pot don't realize the water is getting hotter.

My gut feeling is that we can manage for a good long while either using a portion of crop residues or dedicated crops to produce enough biofuel to support food production and distribution if it becomes necessary-which seems likely at some point in the not too far distant future.This "good long while"-a decade or two is my wag- should enable us to formulate and enact some realistic longer term plans,assumimg the shock is enough to get the attention of the public and tptb.

Removing the bulk of crop residues is not a viable option even over the very short term except on the very most forgiving of soils-dead flat land not subject to wind or water erosion.Such soils can be kept in production for decades by applying either manufactured fertilizers or recycled organics but there is still a slow steady drop in yields unless the fertilizer application is very heavy.

There is some reason to believe that this kind of production system will eventually collapse even if the fertilizers remain available-and it seems unlikely that the necessary quantities of organic materials can be gathered and transported to the farms.

A truly wrenching shift in population from the urban areas,especially the northern areas and those in desert areas would seem to be necessary to solve the collection and transport problem in an energy constrained world.

It would also probably be necessary to eliminate the use of a lot of products containing toxic substances as it would more than likely prove to be impossible to seperate them efficiently from the waste stream ultimately headed back to the farm.

Harvesting too much residue is as I said-or at least implied above-a ticket to a place we don't want to go.

Otoh,if most of us die off,as you seem to be convinced is a sure thing,soil fertility won't matter much-the survivors aren't likely to be concentrated in the middle of the big former corn and wheat fields.

I do not doubt the wrenching changes to our financial system and the liquid fuel dependent industries. However, I am still hopeful that electrification, Natural Gas, nuclear power, hydropower, coal, and perhaps even cold fusion will provide enough basic energy to keep the essential industries (including farming!) going. This is especially so for the US and Canada. Of course, I can't help but agree with the people who are worried about countries with few if any natural resources (Haiti, Bangladesh, Sub-Saharan Africa and some European countries spring to mind) and high population densities.

I do not doubt for a moment that our current wasteful, suburban, "monster-home", SUV-driven life-styles will have to be sharply curtailed if everyone is going to survive the current demographic transitions that are occurring.

I am very interested however in the idea that Peak Phosphorus may prove to be a greater limiting factor than liquid fuels. I would have thought that ash from biofuels, by-products of coal, bitumen and mineral processing and recycling of human waste, and animal by-product processing might help to mitigate the impact of the Phosporus peak. After all, the Phosphorus is not destroyed but only changed into another form after being used on the farm.

Thank-you for excellent article. I am glad to see some more optimistic viewpoints (not because I like comfortable lies, but because I think that this is closer to the truth than the Doom and Gloom I have seen).


Important thread, touches my world-view, will follow it through. Darwinsdog, I agree. My academic training as a biologist is a while back now, but I mastered about microbial-plant-protozoa interactions and can say that what I found was that there is a lot more to plant growth than nutrients. There are important spatial and hormone-related interactions in the soil influencing plant growth which c not be attributed to nutrients alone but rather depend on organic soil structure. Greetings from Germany.

Greetings ciliata. I hope you stick around The Oil Drum. There are some very knowledgeable petroleum geologists & others who post regularly here, but the site is sadly lacking in biological & ecological perspicacity.

I agree. I would love to see TOD have an expert bat-biologist member, but my guess is they are too frantically busy and/or massively depressed to have time for postings. For any unaware of WNS:

Sounding the alarm for bat health

..With the fungus already wiping out 1 million bats, "that's about 700,000 tons of insects that weren't eaten this summer because those bats weren't there," Redell said.
The article is good except for the poor journalism math error above. My guess is that it should be pounds, not tons. The point is still valid as it takes a lot of mosquitoes to equal a pound. 10,000?

EDIT: 10,000/pound is way off if a single tiny bat can eat 3,000 in one night. Probably more like 3 million blood-suckers to the pound.

For what its worth I saw a few bats the Berkshires in western Mass this summer, even though there have been colonies disappearing in the area. I considered it important that I saw any bats at all, and a cheering sight.

Also, my wife is an organic gardener professionally here and she is all about compost and the importance of all the multi-level interactions of soil components and the problems of nutrients being less or even unavailable if the soil is not a living structure... a living organism, really.

I haven't seen a bat this year-and bees of any kind are fewer than anyone can remember,although some honey bees are doing just fine.Other vigorous hives located only a few feet away died off during the spring-when bee forage was plentiful.

Our bats may be suffering locally from a loss of good den trees due t logging pressure. -there are no caves.

Unfortunately I have not worked as a scientist for 10 years now an am a consultant and manager in corporate comm´s now, so my biological knowledge is certainly a good bit oudated by now. Still, some basics remain ;)

Hi ciliata, you sound like a soil fan! :o) I wonder how you find my water based method in the 2nd video above -no soil there, maybe these interactions are taking place in the water I have? Perhaps even more so...?


I don´t know about water, but plant growth enhancing effects concerning interactions between protozoa, bacteria and nematodes have been observed in tomatoes under laboratory conditions before, see


and my former team´s early paper


for reference. I don´t know about the yield, but the roots were a lot larger - do your tomatoes have elongated, more branched root system? Would be interesting to know whether microbial or faunal abundance is greater in your hydro-system than in a regular dirt-pot..(the old scientist inside me is being challenged ;)

Hello Ciliata and Nick.

Nick, that tomato is fascinating. Makes me want to switch to plain-water hydroponics at once -- er, well almost. I guess you put some nutrients in the water? Couldn't find part 1 of your vid.

Ciliata, I'd be glad to hear your comments on what I'm groping into, though without much expertise; just watching and learning as I go along. I'm committed to the no-tillage, highly-enriched living soil community approach, though. That much I'm very clear about.

At the risk of boring TODers who've seen them before, allow me please to post these pertinent links again:

Concerning 'grow yer own fuel', this link is for David Blume's 'Alcohol Can Be A Gas' work, for those who don't know it: http://www.permaculture.com/book_menu/360 links

The whole of David's 'Permaculture' website is a mine of practical and sound theoretical information, and well worth browsing at length: http://www.permaculture.com/

This most striking page is about David's extraordinarily productive holding, on difficult land, but run on permaculture principles, and with his lifelong professional experience behind it. Seconding what David says in this article, I defy ANY industagri system to come ANYWHERE NEAR this level of ecologically-benign production, and keep doing it into the far future, *with just human muscle power*. This is the basic pattern which I'm teaching myself to do on my ground. This is David's striking article: http://www.permaculture.com/drupal/node/141

Comparing the energetic accounting of modern industagri with that of the nineteenth-century horse-powered methods of Europe and the Anglophone diaspora seems to me a straw-horse argument. What has to be done to be meaningful is to compare it with the best of the growing/food-getting methods which might be available in the near future, and on from there. The best prospects of which I'm aware are several of the many branching strands of permacultural practice, particularly with the Terra Preta aspect factored in. That -- TP -- is good too for practical fuel/heat/cooking supplies, with significant atmospheric-carbon re-sequestration included also in the one integrated fueling/horticulture process. A real bonus there, and no need to pay people to do the resequestering; they see the near-immediate benefit in their own soil and its enhanced health and productivity. I speak from personal experience.

Of course, a lot of these arrangements rest on a background assumption of large-scale land-reform, and the breaking up of the gross latifundia, both in the poor world and in the over-rich part, with broadscale redistribution, so that order's of magnitude more common citizens can have individual modest pieces of land to work, though naturally in cooperation with neighbourhood communities as needed, without undue blocks put artificially in their way by minority hyper-rich power-usurping classes (who of course will need to be deposed, one way or another).

Here's another crucial piece of the emerging puzzle-picture: Emilia Hazelip's extraordinary insight, based on the even more extraordinary pioneering work of Masanobu Fukuoka, and on her own subsequent many years as a practical professional food-grower using permacultural techniques (as is David Blume -- "An art can only be learned in the workshop of one who is earning his bread by it"). Emilia's seeing of this fundamental reality -- as she says, still heresy amongst orthodox professional agronomists -- ties in closely with Nick's extraordinary tomato-plant, doing so much better than the other one in the gro-bag, yet with just oxygenated water in darkness around the massive root-sytem, and -- I presume -- modest additions of non-sky-derived nutrients added to the water(?): http://fukuokafarmingol.info/foverfound.html

I have mentioned these initiatives before on TOD (ALL of them based on a great deal of sharp-end practical tinkering experience, together with a deep grounding in the orthodox relevant sciences), but still a lot of the emphasis amongst posters and commenters here seems to stick fast around orthodox ideas which boil down to an unexamined assumption of background BAU, even if some big things like Peak Oil have to be accommodated.

But obviously BAU isn't going to happen. Cliff Wirth's assertions about overall systemic breakdown caused by energy starvation alone, leaving aside the rest of the Synergising Global Crises, are by now too familiar here for me to need to repost links to them. But I have to say that I have yet to see, here or anywhere, a reassuringly-convincing rebuttal of Cliff's basic insight.

With that in mind, it's important to assert -- yet again -- that what people like David and Emilia (and many others, some equally impressive) have been pioneering is systems of agri/horticulture for the million -- no, read billion -- which can be closely-tailored to each particular locality, using the basic handful of permaculture principles, and which run on HUMAN MUSCLE POWER ALONE, and this on all kinds of difficult terrain previously thought 'useless' for any sort of agri.

And yes, of course there are indeed some terrains that would challenge the most ingenious. But perhaps nothing like as many as we imagine in our hitech dreamworld -- especially once we've endured the dieoff which now seems unavoidable, do what we will. Plenty of ancient SMALL-SCALE convivial cultures managed to wring a sustainable living from terrains and local climates which might look just impossible to us at the moment, pampered jades that we are.

Assuming that there's going to be any kind of human society left at the end of The Long Descent, after our current Single Giant Pulse episode of Earth-history has come and gone, we're going to need these new/ancient techniques a lot more than any futile effort to keep hitech industagri going. That was always just "the continuation of the Second World War against other targets". And always destined to be temporary, I think, on a finite planet.


I believe that most of the Oil Drum community is open to your arguments.I certanly am personally in your camp,or camped nearby,in many respects -if we are talking long term.The short term is another matter altogether as I see it,although I am entirely in favor of researching the concepts you discuss and getting some people started actually practicing them who can be future leaders in the field.It's none too soon to get started.

There is one obvious elephant in the room which you ignore in your long comment today-the transition from bau here and now to the future you envision.It's necessarily going to take a long time and its going to be a rough ride at times.

(Personally I will be questioned because sometimes I paint a strictly doom and gloom picture in a given comment and a more optimistic picture in another.The reason I do this is that I am smart enough to know that I don't know what the future holds other than in a few limited respects.)

We desperately need to work out as many strategies as we can to make sure the transition goes as smoothly as possible-and not just to prevent a lot of unnecessary suffering on the part of little kids and others who did nothing to create this society in which we now live other than to be born into it.A fairly smooth transition could be the difference between WWIII and limited wars.

Personally I am convinced that a collapse is in the cards but the exact form it will take-fast or slow,skirmishes or nuclear war,migration from the big cities to the deep country or a fast build out of railroads and the elimination of the personal automobile.....none of us,if we are willing to admit it, or smart enough to realize it, actually know what our society will be like twenty years from now,except in the broadest sort of terms.

Oldfarmermac, your statement

none of us,if we are willing to admit it, or smart enough to realize it, actually know what our society will be like twenty years from now,except in the broadest sort of terms.

is quite similar to one of Dennis Meadows, one of the authors of the Limits to growth (I still remember his words from a speech he gave in Hamburg a couple of years ago on a panel about climate change): "I do not know what the changes are going to look like, but one thing I know: they will be more drastical than anything we have seen in the last one hundred years.", adding that he was "a pessimist of the mind but an optimist of the heart".

I hope for a smooth, prolongued change which gives us enough time to recombine our heritage of ancient cultural (and agricultural) techniques with what we know about science and technology today.

I read the Limits book some years ago.

It is altogether possible that I retrieved this insight from my mental lumber room minus the identification tag it must once have had attached to it.I tend to think in terms of systems rather than specifics and my memory is not as good as it used to be.

If I were writing books rather than blogging I would probably get in a lot of trouble but they tell me that's what editors are for- to catch this sort of thing.

I join you in hoping for a peaceful and productive transition to a better world.

Hi Rhisiart

Thanks for reposting those links, and your commentary. Permacultural gardening that you are doing (per prior posts of yours ) is a great endeavour. I have started a 3 acre permaculture project, in part inspired by you.

Horse farming scales down very well. John Deere in his quest to gain market share for his tractors wrote a book (perhaps more) in it he attempted to analyze the work requirements of old -by hand versus -with horses and then with tractors. (He also championed a mocking campaign to encourage farmers to abandon the teams and join with: 'progress' )

He spent a lot of time emphasizing just how much better the tractor was at plowing than horses. When you looked at his other comparisons, most were on par or very close to that with horses. Pulling a rake -horses are preferred for the speed and the joy of raking with horses (like pulling a sleigh when the snows up on their bellies)

On the horse powered farm the rotation, was such that small sections usually 5-10 acres would be plowed per year, (following the cows rotation ( corn oats wheat then sod ) and if the fencing was done then after the hay was running down it would be pastured for a few years and then the rotation would start again. In other words low impact minimum till with no commercial fertilizer. Horses fit the year well pulling wood in the winter, making syrup in the spring, and planting.
A horse drawn motorized forecart will drive a baler. Run perhaps on biodiesal or ethanol.

Scalability goes both ways. A blacksmith can handle all the equipment needed for horse farming. A change of model towards a no chemical no -till permaculture model extends the productivity of the horses.

I appreciate the effort E.P.

I stand with small scale farmers sequestering carbon, growing quality food and working to preserve fence rows and habitat for wildlife.

Oh and finally this way of farming (or agri-CULTURE )and raising food is soul filling versus soul draining poisoning of the land and toxic rescue chemistry (Rhisiart check out The eco-farm by Charles Walters and C.J. Fenzau )

Percherons rule!

do your tomatoes have elongated, more branched root system?

If one breaks the tap root, yes.

Dig up a 'volenteer' tomato plant VS a transplant at the end of season and note the difference.

Does the volunteer have a more extensive root system?

Exactly what came to mind for me as well. This especially came to mind when winter wheat was mentioned... the organic matter/residue input of the straw that would be removed for biomass is a cornerstone of soil conservation inputs. I wonder if our conclusions are the result of being in the same part of the world?

if u have clay-like soil the organic matter/residue is necessary so during dry cycles air/oxygen can get to the roots.

Russel, feel free to email me. It's always nice to know a more local Oil Drummer.

My comment wasn't meant to disagree with EngineerPoet's post. However, while walking my pastures tonight and thinking about the post, I came to strongly disagree with the conclusion that farming can continue through drastically reduced fossil fuel availability in a way at all similar to today. I mean, farming requires massive subsidies even today. But I'll digress before building up any momentum and get to my point.

I've been playing with low-input farming on a small corner of our property through management intensive grazing with sheep. The experiment has been very sobering.

During the warm six months of the year, inputs and energy use are minimal. Winter sees input use, mostly in the form of hay, rise. The only diesel I directly burn is bringing the hay in each fall. Everything is done with an eye towards avoiding fossil fuel use. I've even experimented with putting up significant amounts of hay with a rake and scythe. (It's doable, but, man, is it ever a lot of work, even just for a family flock.)

Despite spreading clover seed each spring (most of it hasn't taken), bringing in nutrients in the form of winter feed and rotating a Salatin-style poultry (well, ducks) operation over the saddest parts of the pasture, careful grazing control (but I'm still learning), and using portable shade-shelters to encourage manuring where it is needed (generally near hill-tops and away from ponds), it looks worse today than when I started more than three years ago. And in my operation, almost nothing leaves the property. Just the flock's wool and three animals for the freezer. Heck, I've bought six animals.

Granted, much of this is because of the drought we're suffering from. Even so, I just don't see much room for a harvest if sustainability is an aim. One lamb per acre per year seems (way) on the high side to me at this point. Assuming a profit of $40/lamb and one can't even pay the interest on the land.

My hope is that this year is atypical (and it was very very dry), but honestly, I think the "natural interest" that one can take off a piece of land is much lower than almost any of us would believe.

I see farms being able to export electricity from wind and / or biogas then use upgraded biomethane (from overnight wind electricity) to offset some of the use of diesel in the larger machinery using the dual fuel system you mentioned above.

It also wouldn't be impossible to electrify farming operations with overhead power lines.

I like the idea of building huge greenhouses next to all the power stations and use the heat and CO2 to grow lots of biomass for food or biochar

I see two problems:

1. It seems like the land would quickly lose nutrients, if manure and crop residues are used for fuel. Even if only part of them are used for fuel, it seems like it would be a problem over the long term.

2. Fuel for farm machinery is only a tiny part of an integrated system. Even if we can produce enough fuel for farm machinery, can we also produce enough fuel to make farm machinery and the trucks for transporting the crops? How about to maintain the roads that trucks need to travel on to take the food to town?

If the system goes down, it seems like the most your plan might produce is some food for the particular farmer who can manage to provide inputs to existing machinery. Once things start breaking down and replacement parts are not available, even that little would be gone.

Gail, I agree with your general concerns (see my comment below). However, I do think that if we can find enough surplus energy, we'll be able to continue to manufacture replacement parts and even new generations of tractors & machinery even if the larger "system" starts to fall apart. See, for example, the 100k Garages concept for distributed manufacture of things like replacement machine parts, or Factor-E Farm's work at developing an open-source tractor design that could be built through such a distributed network. Of course, we still need to have the energy to operate these, the metals as inputs, etc...

I agree with you Gail. Many proposals for alternative systems actually imply the continuing existence of the present system. The trouble with complex integrated systems is that if they break down they may break down as a whole, so you probably can't cherry-pick the bits of the system that you'd like to preserve.

Also crop residues and animal manures are essential for maintaining soil structure and ecology, as well as nutrient cycling. Biogas plants seem to do this well, I'm less clear about other processes. Do we have any experts on this?

Nobody is better able or experienced at "simplifying when necessary" than a farmer, or for things like maintenance and minor repair tractor parts, a group co-operative of them. I've seen my father repair a tractor engine which had damaged it's crankshaft due to a spun bearing, with only sandpaper, a length of babbit stock, and a LOT of elbow grease. It ran like new for many years after and may still be doing so.

Lengould, I don't doubt it. And think of all those 1950's cars in Cuba, still running, even (reported in a TV documentary) using a mixture of shampoo and vegetable oil for brake fluid. Don't know what a babbit stock is, but it sounds real handy, like elbow grease. I guess he had some of the other grease though. At some point the complex supply chains will be necessary, even for ingenious and self sufficient people. A new chain for the chain saw? There is plenty of literature about the post-crash scavenging phase, and doubtless this will work ok for some people for some time. Probably not for urban gardeners like me - even if there is work, if I need a sharp blade for my pruning saw I have to buy a new one. They are all 'hard-point' and cannot be sharpened! This may seem a trivial point, but it illustrates how completely tied in we are to the existing network for just about anything.

how completely tied in we are to the existing network for just about anything.

Only if you choose to be. I know, if it becomes a problem for me, I'll get out the grinder and welder and start making my own cutting faces from raw heat-treated steel after the truck springs run out.

You're assuming that gas and electricity will be around to run those tools. If things get so bad that you can't get saw blades, I'd say the chance there will be electricity for the grinder and gas for the welder. And even if there is electricity, it may be too expensive to use on those tools. Just keeping the fridge running and some lights on at night may run $100s of dollars.

The fridge and lights are much lower value than machine tools. They go first.

Canned and dry goods, with fresh foods only in seaseon.

Slight correction. The lights might stay. I just recalled a story from a few weeks ago about a small businessman in a poor area who was investing heavily (for him) in a solar power system so that he could extend his productive hours with reliable lighting.

lengould, I agree that farmers are a resourceful lot but I think the point has been made (and I agree) that the farm machinery of today is a different and much more difficult animal to make "field repairs" to.

There is another consideration here. I sell farm machinery and several times a day, I get calls from growers who are broken down and need a part TODAY. When we do not have one on the shelf, it can be a real problem. Spray and harvest schedules are time critical. A tractor down for just a few days at the wrong time can mean a significant crop loss.

I'm certainly aware of that, but I'm also of the opinion that if the choice comes down to plowing with mules or severly simplifying that tractor, I know which one I'd be doing. A diesel engine is a thing of awesome simplicity at its core provided you leave the injection pump to experts, and any decent machinist could rip apart an 18 speed automatic transmission, scavenge parts, and come up with a simple gearbox that would serve. A doomer investor would likely be wiser to stockpile some injector and pump repair kits and a good cross-section of bearings, rather than canned goods and ammunition. Maybe a good simple knee mill too...

Once you break away from the high finance tax shelter mega everything model you realize very quicly that you can own four middle aged tractors in good working order for the price of one new one. Ditto the trucks and everything else.

Even so , breakdowns can be a real problem-making hay in front of a storm is no joking matter.

But breakdowns are not going to seriously hinder total production-I would guess that out of a hundred combines in good condition-(well maintained and prepped in the off season) not more than one or two will suffer a serous breakdown within sixty days-the kind of breakdown that can't be fixed right in the field in a matter of hours and that most of these will be the same old same old- the tractors we use in this part of the world for instance need tires ,belts starter motors,radiators, batteries ,etc, often but axles, clutches, engine overhauls , etc , only at very long intervals.

Perhaps to put this in perspective ,the average automobile actually BREAKS DOWN only at long intervals -if maintained properly , lots of cars go over a hundred thousand miles without a single on the road failure of any consequence- the kind that requires a tow.

And cars are throwaway products.

The trouble with complex integrated systems is that if they break down they may break down as a whole, so you probably can't cherry-pick the bits of the system that you'd like to preserve.

I am not sure this is true. They MAY break down as a whole, in the sense that it seems that "things don't work like they used to"... but if there is any way what so ever to make the system work at all, people will find it. By using common sense and looking at the present situation. (Which is basically the only thing capitalism does well.) I think people would cherrypick the most important bits of the system and preserve those. SUVs will go before tractors do, for example.

1. It seems like the land would quickly lose nutrients, if manure and crop residues are used for fuel.

If ash is being produced in a gasogene at the field, the easiest thing to do with it is spread it on the field as it comes out of the cyclone trap.

Production of pyrolysis oil leaves most of the solids as ash.  Transport of raw biomass is expensive, so processing would be done close to the source.  This would make the return of ash fairly easy; even exporting the energy does not have to deplete minerals significantly.

2. Fuel for farm machinery is only a tiny part of an integrated system. Even if we can produce enough fuel for farm machinery, can we also produce enough fuel to make farm machinery and the trucks for transporting the crops?

The rail company which sponsors NPR claims 423 ton-miles per gallon.  Figuring 2000 miles to an arbitrary coastal city, 150 bu/ac and 56 pounds per bushel, this is about 20 gallons of fuel per acre of production (more than I expected).  If used as pyrolysis oil, it would require perhaps 4.2 GJ/acre of biomass.  This is much less than the expected production.  Also, rail uses less than 4 billion gallons of fuel per year; we can expect petroleum supplies to be sufficient for it for some time (and electrification of rail should be one of the first responses to our situation even without an immediate crisis).  Water transport is more economical yet, and as I noted before, heavy diesels can be run on slurried coal if petroleum is not available (and there is time to convert).

If the system goes down, it seems like the most your plan might produce is some food for the particular farmer who can manage to provide inputs to existing machinery.

Quite a bit more than that (the local surpluses are large), but a buffer against short-term shortages is all that is required to prevent more dominos from falling.

The rail company which sponsors NPR claims 423 ton-miles per gallon.

The nice thing about this type of figure is that it is systemic. Complicated logistical factors like switching and moving around empty cars are automatically included in the accounting. The rail companies simply compare their total fuel appropriation to their total ton-miles of freight shipped. The latter data are carefully tabulated because it's what they use to charge their customers.

Our nation used to rely almost exclusively on rail for the shipment of freight, from actual beginning point to end point. Nowadays a large percentage of rail freight is intermodal, meaning the first and/or last several hundred miles of a journey is by road. I'm convinced that this trend will at some point reverse itself, with close proximity to rail connections becoming once again of vital importance to businesses of all sorts. We will probably end up with our cities becoming once again more crowded and dirty, as proximity to these nodes of distribution becomes a key factor in where people choose to locate themselves, which it currently is not. My impression is that this is much more of an issue - and will require much more change - on the consumer end of food distribution than on the production end. That is, I would guess there is currently far more fuel used by suburban shoppers driving to supermarkets than by farmers driving their grain to the railroad.

I agree that rail development needs to start right away. When gasoline went up to $4/gal, public transport across the nation was flooded.

However, I don't really see the kind of movement necessary to accomplish what is needed, do you?

If ash is being produced in a gasogene at the field, the easiest thing to do with it is spread it on the field as it comes out of the cyclone trap.

Except now you're changing the ph of the soil. That's not a good thing.

Most ag soils need liming to raise pH periodically, and most ash is basic, so this could work out alright but some numerical analysis of how ash might replace ag lime would be good to have.


But that is very different that what EP is saying. He's suggesting you just dump all the ash back on the fields like you would have done with the manure or crop residues.

Farmers are very careful to manage their soils. Wholesale dumping of ash on their fields would be a very bad idea if you are looking to get those inputs back.

Gail's point is still very valid.

Most crops require a pH of 5.5 to 7.0. Many productive ag soils (organic soils excepted) are already in this pH range. Dumping the ash to them can easily raise pH levels above what is optimal (and induce micronutrient deficiencies). Some crops -- potatoes and blueberries are two that come to mind -- perform better in more acid soils. Soil pH has to be carefully managed. It is overly simplistic to assume that soils, in general, can be made more productive by raising the soil pH.

In that case, I will (with no small amount of snark) suggest neutralizing the ash with pyrolysis oil, which is highly acid.

More seriously, you have to consider that the amounts involved are relatively small, and you'd have a far larger effect from a grain fire.  The effect would also be offset by the uptake of the same minerals during the next growing season; the calcium and potassium might become hydroxides shortly after meeting the soil, but they wouldn't stay that way.

More seriously, you have to consider that the amounts involved are relatively small,

I don't think that's accurate at all.

Soil PH is something that has to been carefully managed. In addition to keeping the PH in the correct range for the target crops Soil PH has a significant impact on the amount and type of fertilizer used.

Liming to increase the PH of the soil is usually done sparingly and infrequently (if not you are probably growing the wrong crop for your soil).

Wholesale dumping of ash on the soil to regain the inputs lost from manure or crop residue will upset the soil ph.

I've never heard of Pyrolysis oil but a quick wikipedia search come up with this tidbit
"The pyrolysis oil is not stable reacting with air and degasing."

I have no idea where you are getting this snark from?

I'm saying something that should be blatantly obvious:  if you burn 10-20% of the stover and leave the ash on the field, you are going to have a much smaller effect than if a fire burns the entire crop (grain included) and leaves it all there.  If the latter does not damage the field, neither will the former.  Prairie soils were developed in part through frequent fires, and that is the origin of much of the fertile land currently planted in corn and wheat.

I honestly have no idea what soil organisms would do with compounds like potassium formate, but if you are looking to neutralize the alkaline nature of ash before returning it, that's one way to do it.

20% harvest of 1.5 tons of corn stover/acre is 600 pounds/acre. Typical ash value for corn stover is 6% which leaves the ash disposal burden for an acre at 36 pounds, a little less than a pound per 1000 sq ft.

There is a difference in burning in the open field though, thats a low temperature burn and leaves behind lots of char.


I'm not sure that it is exactly what others may mean by the word but anyone who wants a small sample of pyrolysis oil,or something close anyway can make it easily.

Fill an old gallon steel paint can with wood chips(put the can in a hot wood fire first to burn out any paint residues) drive the lid on tight,put a nail hole in it, and place it in a hot fire with the nail hole oriented to one side away from the flames.

You will be rewarded with a highly flammable gas jet shortly.If you place a large heavy object such as a chunk of steel or a stone where the jet will strike it,an oil will condense on the surface.

You will additionally be rewarded with a pound or so of light fluffy charcoal-perfect for a fast fire ,great for burgers-if you make several cans full.

We used to make five gallons at a time in larger buckets when we burned the brush(pruned limbs) from the orchard.Burning a very substantial quabtity of wood in one spot never had an adverse effect on the soil in terms of practical farming-the burned spots have always been prized by local orchardists as mini garden spots.

Of course our local soils do tend to be a tad acidic-enough so that we do usually find it worthwhile to apply some lime every five to ten years.

Wood ashes are about 30% CaO, 1-2% P2O5, and 5-6% K2O. Conventional belief is that a ton of ashes is about as neutralizing as 4000-5000 pounds of CaCO3. Stovers and grasses would also have significant levels of silicates.

Edit: I got that backwards. A ton of CaCO3 is about as neutralizing as 4000-5000 lbs of ashes.

Using barrett's figure for ash content above, 1.5 tons/ac of stover would burn to 180 pounds of ash.

Shouldn't we be storing up grain for a seven year supply?

Back at the end of WWII every small town in the midwest had a set of grain storage buildings. Sort of biblical.

We should -but we won't,because the world runs on money nowadays and money has too much interest value for grain to sit around accumulating storage costs and taxes.

A strategic grain reserve makes as much sense as a petroleum reserve.

Admitting that one is needed is not going to get anybody elected.

Hopefully we will not suffer the misfortune of a new virus wiping out a staple crop such as wheat,corn ,or rice ...hopefully.......

i have read we are here due to our ability to store grains for low harvest year[s]!

Thanks for some very important quantitative data. This should improve some conversations, for sure.

On the other hand, I have always been told that energy use on the farm is only a small portion of the total energy input to modern agriculture -- distribution, packaging, financing, transportation infrastructure, etc., etc., using far more energy.

Actually, since the dawn of agriculture, the problem seems to have been what to do with the surplus -- and usually it has gone into powering the division of the population into the wealthy and the destitute classes. Even in the famous Irish Potato Famine, English (and some wealthy Irish) farms on Ireland were exporting beef and wheat to England. And in our own time, no one can say that the stinking, starving slums of Lagos are that way because there isn't enough oil in Nigeria!

Realistically, EP, you seem to have proved once again that if we can get our collective acts together, there is plenty of energy available to make life agreeable for everyone. If we continue in the present paradigm -- even adding exotic energy sources -- we will recreate the primordial slime and evolution will start all over again.

we will recreate the primordial slime and evolution will start all over again.

Yes 'tis the way the world works, nothing to worry about, move along - to assume that 'survival of the fittest' doesn't apply to humans is clearly wrong, when the environment we are adapted to changes enough we will be gone. It is clear from the world's geology and climate history that things never stay the same for very long - I have seen significant changes in just 50 years.

There are plenty of places in the world where complex societies have collapsed - and none have been as complex as ours, nobody really knows how it works so we can't even guess what the failure mode will eventually be.

All we know is that at some stage intensive agriculture will be unable to support BAU growth, plants need many inputs - who knows what the Liebig's minimum will be to cause peak food supplies - it might be crude oil, but I doubt it?

While I think that the energy analysis works if we only consider energy used on the field, I'm concerned about the amount of energy required to make that energy available.

For example, while it may only take 750 MJ of energy per year per acre actually burned by the tractor, the energy required to put that tractor into operation is significantly greater. I think this is reflected in the fact that the financial return on investment for famers is nowhere near as high as the energy return implied if we just look at the energy used on the field. This additional expense--the capital cost and maintenance of the tractor, for example--is representative of at least some amount of additional energy that is a "but for" requirement of using tractors to plough fields. How much energy is required (including all ores, processing, design, manufacture, the energy used to produce the machine tools and plant used in manufacture, the people who work at these facilities, distribution, maintenance, etc.) to allow the farmer to burn those 750 MJ/acre/year? It's only a proxy, but the fact that most (?) farmers are barely scraping by (especially if you eliminate subsidies) suggests to me that the inclusive energy balance using tractors is not nearly as positive as when looking only at on-field energy use. My understanding is that the cost of a purchasing and maintaining a tractor is significantly more than the cost of the fuel it will burn in its lifetime, suggesting that there's more energy locked up in the tractor itself (burned off-field) than is ever burned by that tractor on-field. These same considerations apply, to some extent, to the additional energy inputs required to get the fertilizer onto the field, modern seed production, pesticides/herbicides, distribution/processing of produced crops, etc.

While I don't necessarily think that farms don't or can't produce positive energy balance under mecahnized operations, I don't think we can say that they do with any confidence until these other necessary energy inputs are quantified. I agree with your conclusion that it looks like we can keep existing farm machinery operating with only fuels produced on-farm for a period of time, but I'm not convinced that we'll be able to produce and operate the next-generation of such machines with only fuels produced on-farm (or without using up all the energy surplus otherwise produced by such farms)...

Interesting post.

I agree with Jeff that the fuel energy requirements could be higher than 750 MJ.
Check out Energy use and economical analysis of wheat production report in this post.

In terms of total energy equivalents the following table summarizes the production of wheat in the study:

Inputs (MJ/ha) - 47,078

  • Human Labour - 317
  • Machinery - 4,574
  • Diesel fuel - 12,267
  • Chemical fertilizers - 14,654
  • Farmyard manure - 4,575
  • Chemicals - 260
  • Water for irrigation - 4,230
  • Seeds - 6,201

Outputs (MJ/ha) - 92,786

  • Grain - 66,368 (4,515 kg)
  • Straw - 26,418 (2,113 kg)

Per acres numbers would be smaller. There are also dependencies on geography and other factors.

Some of those inputs are clearly questionable. Farmyard manure if used would be a ready-at-hand item, not an off-farm input. Water for irrigation may apply in some areas you know of in Europe or the western US, but is a rare input to crops where I'm familiar, like wheat which would become the staple if starvation loomed.

After a quick look through the paper, it does seem to support those high off-site energy costs, measuring 73.27% of "indirect energy" (seeds, fertilizer, manure, chemicals, machinery) making up the total consumption.

It claims the "indirect energy" included the embodied energy in the machinery, but I didn't read the deeper reference. That being said, the "Machinery" (which may include electricity) energy inputs cover 9.71% in the study, while diesel is 26.05%.

Some logging operations in my area have picked up on using animals for reasons similar to what you bring up. You can feed a couple of teams of animals for a year for what a tire on a skidder costs. Then there's the woodland damage caused by heavy equipment, recent restrictions require that the loggers clean up the logging roads and replant trees if they caused excessive damage to the undergrowth. The animals are low impact and they save considerable time on the cleanup efforts. After the leaves fall you cant see the logging roads left by animals. The skidders leave ruts that would be visible for years if you didn't go back and clean it up.

There's also other aspects to the growing of the fuel which aren't always directly comparable. Oil seeds require tillage, pasture and hay don't. In many regions farms invariably have hillsides that don't till well and wooded areas that can provide some summer feed. Getting the nutrients back from any type of fuel processing would no doubt involve the farmer buying it. Cover crops can be grazed, stovers are somewhat usable as animal feed so the 1/4 to 1/3 acreage requirement doesn't have to be dedicated, it can overlap some with the cropland with no additional nutrient requirements.

Then there's soil compaction which definitely has a cost, but difficult to quantify.

Oil seeds require tillage, pasture and hay don't.

I'd suggest some application of rose-coloured glass(es) here. Pasture and hay do require tilling, eg. re-seeding of the productive species every third or fourth year. Typically done as part of a three or four year grain crop rotation on low-intensity mixed farms such as the one where I grew up. And fertilizing, else the production drops to near zero quite rapidly. Where Dad used to spend his winters logging "for the man" with horses, in camps with bunkhouses intended to be occupied for entire seasons, no transport available, in order to cover the costs of spending his summers growing and harvesting hay so he could sell it to the loggers (he used to walk out some weekends, and tell us of the wolf tracks he'd see on his return trips where they had followed him). Most other farmers in that district ditto. It is extremely resource intensive. Logging trucks would regularly pull in to haul hay back to the camps. Large numbers of loggers and horses required to do the job of a single mechanical crew today, eg. 2.5 cords / day vs. 100 cords / day.

I'd suggest some application of rose-coloured glass(es) here. Pasture and hay do require tilling, eg. re-seeding of the productive species every third or fourth year.

Thats clearly wrong. Some types do, but some != all. I'm right not about 40 ft away from an hayfield that was last seeded about 15 years ago. One several hundered yards away at a neighboring farm hasn't been tilled or seeded since 1983. About half of the pastures within a half mile radius from where I write this have never been tilled.

And fertilizing, else the production drops to near zero quite rapidly.

For tilled grain crops yes, production doesn't quite drop so rapidly to zero for pasture and hay, much slower so if you're just feeding draft animals and not exporting nutrients by selling cattle. I can think of about a dozen pastures and hayfields near me that haven't been fertilized in more than a decade. Productivity is maybe 60-65%, but that's substantially more than zero.

Large numbers of loggers and horses required to do the job of a single mechanical crew today, eg. 2.5 cords / day vs. 100 cords / day.

"Cord" is a volume measure of firewood and is meaningless in the context of logging, board-feet is the metric used for logs. Teams used locally typically move about 3000-4000 board feet of lumber in a day. The extra time the logs spend in transit getting to the truck isn't that great of a penalty because the portion of the day taken up by moving tree from woods to truck wasn't that great to being with. Most of the operations around here are small with a single cutter. Two teams will give a single cutter all he can do.

Very interesting analysis, mindful of a conversation Gail and I had earlier this year around the question whether the biofuel sector - or agriculture - could support its own energy requirements. Whether agriculture could support its own requirements and still produce sufficient crops. While these insights are helpful, time and experience will define the energy return boundaries.

History suggests that EP is optimistic; if agriculture fuel productivity exists potentially in the fields, why has it not been adopted? Even when oil was 'cheap', money is never, particularly for farmers. Oil has been less and less cheap over the past ten years and farmers are more dependent upon diesel fuel than ever, even with new technology. Within the (more or less) efficient ethanol distillation, the EROEI argument is undecided. Corn stover (or switchgrass) biofuel bogs down on the feedstock transport issue. 'In the field' energy sources are dispersed. Collection and concentration is energy expensive.

So to are the machines that work the fields, these come from factories and get to the field by mechanized means. All this is embedded petroleum fuel; the great bulk of it, in fact ... along with the food processing, packaging, distribution and retail. It is the downstream 'tail'; the 2,000 mile caesar salad, that is the weak link in the US food supply, as it was during the Great Depression. Today, farmers are scarce and most Americans don't know any farmers. To rely on individual farmers as Americans did during the 1930's is improbable; we rely on grocery chains and diesel tractor trailers, ships, container- loads of imported fruits and vegetables. The embedded potential replacement energy of much of our most productive cropland has been paved over with more embedded (asphalt) energy. If the current, widespread, just- in- time food distribution fails there is no replacement; food will rot in warehouses and storage bins while people beg for canned goods in the cities.

This is a continuing process; it is common overseas even in drought stricken or otherwide agriculturally- challenged areas; lots of food 'in the world' but nothing in the towns or stores or markets where the people in the streets are hungry. Usually, it is the lack of earning power - also petroleum dependent - that prevents hungry people from getting food.

Cutting off this last 'tail' means cutting off paid employment, removing systems efficiencies (as well as the massive and highly integrated finance structure built on top) that directs paying customers and other systems efficiencies to the farmers. Farmers seeking to be fuel self- sufficient would have to be so under very constrained business conditions. The whole on- farm fueling cycle might be functional - on paper - but hobbled because the one company that makes diesel injector pumps or large, agricultural tyres ... is long out of business.

Once the current crop of farm machinery breaks down, finding replacements or having these available without large petroleum inputs appears to be questionable. Where do we go from here?

I apologize for wandering far off the beaten track; the possibility that agriculture could produce both food and be energy self- sufficient in its own 'back yard' is useful. To make it work on a broader scale needs practical experiments and the development of a more efficently scaled ag context. The current scaled, cash- flow model is dominant, even as it is under severe stress. This model would have to be replaced by ... what, exactly? There needs to be more farmers; more durable, long lasting and more easily repaired farm machines, more localized markets, more efficient transport from farm to consumers, less 'technology' that comes from central and patent- controlled sources, fewer intermediary processors, less 'antagonistic' technology (which requires energy- expensive cleanup or mitigation or ... kills the customers and farmers). Without all of this in place, fuel self- sufficiency will be stranded and of not much use.

if agriculture fuel productivity exists potentially in the fields, why has it not been adopted? Even when oil was 'cheap', money is never, particularly for farmers.

And the capital investment for bio-fuel production (and the R&D upstream) is scarce, while aside from a few situations this past century oil has been relatively cheap.

The exceptions are worth looking at.  In WWII, oil was expensive enough to make gasogenes attractive (or even mandatory, where petroleum was rationed or unavailable).  This is an old problem, and I'm not suggesting any radically new solutions.

You put your finger on it; the change over has a very high price tag and investment lags. Ag was a lot less energy- intensive going so far back to the first 1973 US energy crisis. Farmers were getting hammered by costs and low crop prices.

The result of an investment lag and a lot of farmers folded.

I have a description here somewhere of how to make charcoal.
With Charcoal i can melt the "iron pan" found hereabouts, for casting iron in moulds.
I also have an old book on casting as a hobby, showing the author building a small model piston engine.
This could very likely run on your biofuels.
This in turn could drive a shaft, and, via cast cogs, drive wooden wheels.

This level of homemade tech is very 1492, but fairly doable, needs only wood and ore.

"Steel is recycled an unlimited number of times and the energy recovered back into the product."

"about 55 percent of “new” steel is now melted from scrap steel" "Between 1990 and 1998 alone, intensity has dropped from 20 to 18 million Btu (MBtu) per ton. This figure is projected to decrease to 15 MBtu/ton by 2010 with an asymptotic trend towards 14 MBtu/ton." ENERGY USE IN THE U.S. STEEL INDUSTRY: AN HISTORICAL PERSPECTIVE AND FUTURE OPPORTUNITIES

Given a typical ag tractor which can operate a 1000 acre farm may weigh 10 tons, almost all steel, it embodies at present rates about 200 mmbtu. In a 15 year life it may burn 15,000 gallons of diesel, at 139000 Btu per gallon. That's 2,085 mmbtu. Even doubling the embodied energy of the tractor to account for misc. inputs leaves its lifetime fuel btu's 5 times grreater than its embodied energy. In a "crash" scenario when much more scrap is available than demand for steel, the embodied energy of 100% scrap would drop to perhaps 1/10th. Then of course it's implement suite also embodies a lot of energy, also almost all steel. Let's say fuel is 2.5x greater nergy than manufacturing today. In future, all depends on issues like scrap content, usages, etc.

You can go to the nearest John Deere dealer and price a 7630 and get a rough idea of how much embodied energy is in a tractor.

At Unballasted Operating Weight, lb. (kg) 17,738 (8,045), its a little smaller than my estimates, but in the ballpark. Obviously a LOT of the price of these units ($101,000) is not simply input energy to the steel used in their manufacture. Most of what isn't is of questionable necessity. Does a farmer really need an 18 speed automatic transmission, climate controlled cab, multi-band radio / CD player, deep-cushion hydraulic seat? Of course an 18 speed transmission may help contribute to fuel efficiency in certain circumstances, but I've done a lot of heavy logging with 200 hp tractors with 2 speed allison trany's, and as a kid on the farm our larger tractor had only a 6 speed manual which served quite well though I don't recall ever using first gear.

lengould -

I am really glad that you brought this up, as I was going to say something similar.

I think there is a general misconception around here that the imbedded energy of heavy machinery is a lot greater than it really is. I got into this sort of an argument on several occasions regarding wind turbines.

In fact, I think your back-of-the-envelope calculation is bit on the parsimonious side in terms of the total amount of fuel consumed during the life of a large tractor. You appear to have assumed that all the fields get only one pass of the tractor per year. that may not always be the case. Plus a large tractor, with proper maintenance and rebuilding of key components should last much longer than 15 years. (Hell, that's even a young car for some people.) So if you double the life of the tractor, your 5-to-1 ratio goes up to 10-to-1.

So, my own WAG is that your 5-to-1 ratio of life cycle fuel consumption to embedded energy is probably too small by at least a factor of two. But I think you've made your point, even with perhaps overly conservative assumptions.

The other thing that people around here seem to get wrong is the notion that the price of a large manufactured item correlates directly with energy input. However, in most cases, the direct or even second-order energy inputs represent a relatively small fraction of the overall cost of production. It takes about the same amount of energy to manufacture a $120,000 Ferrari as it does a $20,000 Chevy. So one must look at this on a case-by-case basis.

"I think there is a general misconception around here that the imbedded energy of heavy machinery is a lot greater than it really is."

As one who has worked as a mechanical engineer in developing processes to manufacture aircraft/aircraft parts I think your assumption is false. You need to take a trip to a midwest tractor or heavy equipment plant (Peoria, IL or Decatur, IL or Fargo, ND)

Let's examine the process to make a gear for a power take off speed reducer:
Steel made from scrap, formed into a billet of 20 tons. Cooled billet then reheated to roll into smaller shape, perhaps a round bar 10 or 12" dia. Cooled bar is then shipped to another location where the rounds are cut with oxygen-acetyline or plazma torch into smaller pieces and reheated, then formed by drop forge or heated to melting for casting in mold. Cooled rough forging or casting is trimmed with oxy/act. torch or plazma torch, then placed in CNC machine to cut O.D. and I.D., then moved to another machine for cutting teeth and lastly moved to another machine for hole drilling or spline cutting. Finished dimensional part is then induction heated or flame heated and control cooled for surface hardening. Part is then checked for final inspection of dimensions and perhaps hardness, boxed and shipped to tractor assembly plant (maybe across town or across Pacific ocean). The repetetive heating/cooling and handling by machines and conveyors takes a lot of energy, not even counting the factory's utilities of lighting, heating, cooling.

I would guess that the embedded energy of one gear has five to ten times the energy of the raw steel used in making it. Multiply that by thousands of parts in a tractor or combine and you can see why the steel is just one small energy input in building a piece of heavy machinery.

Mark S. Bucol

mbnewtrain -

I am quite familiar with both primary metals production and also heavy manufacturing. In fact, many years ago I was doing some environmental work for Caterpillar and had visited there facilities in Peoria. So I am well aware that these operations can be quite extensive.

Yes, there is a great deal of energy expended in metal forming, particularly if there is multiple heating and reheating. Some components are more energy-intensive than others. However, I would still have to say that for large steel manufactured objects in general, most of the embedded energy is associated with smelting the steel from the ore. One gets a hint at this just by the size of blast furnaces and iron foundry cupolas. The heat capacity of iron is not all that large, so one can heat and reheat a piece of steel many times before the total energy expended approaches that required for reducing the iron from the oxide ore.

Anyway, I'm sure that the automotive industry has done many studies regarding the energy content of their product, and it would be interesting to see just what fraction of the total energy went where. Heavier vehicles such as large tractors probably wouldn't be much different.

Dunno, automobiles look like many of the components can be simply stamped out on a press from relatively thin stocks. A tractor is big iron nearly all the way thru. And its not just the tractors themselves, the productive capacity to provide us with tractors has a footprint I'm sure.

Disclaimer: I have no hands on manufacturing experience.

1) Please see my comment almost at the end: I would have thought that it was clear that this article was just addressing the short-term, in which farmers had to cope with a fuel shortage with their current equipment. That means that embedded energy isn't relevant.

2) Manufacturing uses very little oil. The US, at least, has plenty of electricity and natural gas, which is what manufacturing primarily uses. So, it really doesn't matter how energy intensive manufacturing is - it isn't going to halt because of PO.

"Manufacturing isn't going to halt because of PO............"
No it won't halt but it will slow down a hell of a damn lot.

Maybe manufacturing will ignore PO..........but will the consumer?
I guess you ass ume BAU and a plentiful supply of consumers to purchase the manufactured material.

We will continue to make things and buy them after PO, but it won't be BAU.

In the best case scenario maybe people will learn to slow down.

Why, specifically, should manufacturing slow down dramatically?

I assume you mean an absolute drop, not a drop in growth.

It seems clear that oil-importers will see slower growth due to their trade deficit with oil-exporters. And, clearly, investment in new energy systems will pull investment away from other, possibly more useful things. And, clearly, we could have more bank panics like we saw last year.

But why would it be likely that economies would see an absolute decline?

Mark,your argument certainly sounds convincing but I am not convinced.
In the case of a gear you are undoubtedly correct.

Presumably everybody all along the way operates on the average at some level of profitability on the average.

The energy embedded in a ton of iron ore delivered is certainly less than the amount of energy than can be bought with that amount of money-if ore is two hundred dollars delivered ,there must be considerably less than two hundred dollars worth of coal,ng, and diesel involved in mining it and getting it delivered,considering that that two hundred covers wages,taxes, rents, insurance, interest,etc.

There should be a simple way to figure this out well enough to get a ball park answer.

Somebody here should have some idea how much electrical power and ng or coal is used at a typical plant that makes for instance engine blocks and at another plant that manufactures transmissions for instance.from there to the amount per block is one more step-production level only is needed to get the energy per engine block.

These two components are I would guess the most energy intensive of all due as you say to lots of machine tool work and extensive heat treatment.

If we have a rough idea how much energy goes into the transmission and engine,that should give us a pretty good upper limit for the entire machine,as the other components pound for pound would use much less,except the final drive line gears and a few suspension components such as spindles which are also heat treated.

Of course this approach is only good to get a rough upper limit so far as I can see.

Part of the problem is that to do speculative analysis we need MJ/Product Unit to make a guess as to how energy input changes will impact the process.

Commodity prices are set on a market completely independently of production costs in the short term, so not much revealing there without a detailed sector analysis including new entries and exits from the supplier side of the market at relative price/expense points as well as using some method to control for labor costs causing country source shifts as we have seen especially in the steel market.

Much better to use actual end-to-end energy usage figures for companies involved where available to get current figures.

For speculative figures it would pay to remember that cheap energy since the 19th century has lead to energy being used to replace time or labor as a primary input, there is likely to be considerable room to reverse those trades for many processes should energy prices get too high.

Agreed joule, on the single pass over 1000 acres. I had thought I'd provided for two passes (no-till seeding + harvest) but missed putting it in. Its also to be acknowledged that in very dryland areas (southern praries of western Canada) a lot of land is left fallow every second or third year to accumulate moisture, and is usually given at least one light tilling pass in the fallow year for weed control. Perhaps that weed cultivation is replaced now with a spray pass of herbicide which would be even less energy use than a light till.

jeffvail hits the nail on the head.

Engineer-Poet's article is sort of compendium of poor analysis with the most obvious error being the failure to include the energy costs of making, maintaining, and replacing again and again forever the machinery of the farm.

As a Kansan with many friends who farm, I can also say that most would simply laugh at your conclusions. Almost every farmer who is not a corporate entity works an outside job. If they are married, their spouse does as well. And, even with those outside jobs, they often fail. Your rosy outlook would seem to imply that given the incredibly cheap energy cost of farming and absolutely fabulous energy return off the land, every farmer in the land should be magnificently rich if not through crop sales (but most farmers would laugh at this because more food means lower prices) then through the sale of all the extra energy they are pulling out of that sun blessed land in what I must assume is a sustainable way.

The only people I know who make it on farms in this region without outside income are organic, localized farmers, using intensely sustainable methods. The Mennonites come to mind. And the nice lesbian couple up the county road who are entirely self-sufficient.

I am surprised the editors let you print this spurious article with its techno-optimism especially since it is so blatantly skewed and out of touch with reality on the ground/farm.

Of course, the paradigm of the moment will strive mightily to continue in exactly the manner you proscribe, but then millions of people still smoke despite the evidence of its inherent stupidity and health risks.

These types of articles will be responsible for many deaths by prolonging the use of a dying/doomed paradigm by offering the hope of BAU.

So sad.

That's a little aggressive... I never read it as "this will allow BAU."

I think we need to decouple the ideas of positive EROEI from positive cash flow. This has been said so many times on this forum, I'm surprised it's still being brought up in these comments.

There are technical issues with available data that could poke holes in this, but the fact that farmers have a hard time financially is in no way connected to the potential net energy flow of their farms.

Farmers are no different to amy other business, they must make a profit - IMO when oil becomes even slightly short supply the costs will rise enough to damage the economy, again and again.

The farmer may not find customers that can afford his crop if it is priced to make a profit, so the farmer leaves the field fallow, no profit but minimises losses. Adequate profits will determine if a shortage of oil will damage food production.

For some idea what will happen, ask yourself what happened in the 1930's depression?

I'm sorry to have attempted to steal your thunder xeroid I should have read the whole thread before I commented above. I more or less reapeated exactly what you wrote.

Farmers are no different to amy other business, they must make a profit

Make? How does government crop subsidies equate to a "make"?

It doesn't matter where the income comes from as long as it is more than costs.

The whole point of the subsidies is to encourage farmers to aim for an affordable surplus so we taxpayers don't starve even in a bad year.

There is no substitute for food, I would rather pay a subsidy than starve.

There are technical issues with available data that could poke holes in this, but the fact that farmers have a hard time financially is in no way connected to the potential net energy flow of their farms.

Which begs the question: If farmers can't run a profitable operation, then who will we bring in to run our farms? The engineers?

When farmers stop producing the chronic surpluses of recent history, prices will rise to make farming much more profitable.  Kind of like peak oil, only renewable.

If rising incomes fund the rising prices.
IMO "Chronic" surpluses should mean chronic gluts and low prices now.
Over consumption is real though, it drives economic growth, we relied on it and pandered to it and it's why the population is predominantly fat.

Joe farmer will always try to (predict) produce and sell to the demands of the market.
He will try and sell as much as possible into high prices and diversify (if possible) with low prices.
Producing more when prices are low probably means government subsidies.
Over supply should be transient and adjust commensurate with market demands. I've been wrong plenty of times in the past with my assumptions, this may be another.

chronic surpluses of recent history

and yet ... at least 1,000,000,000 are malnourised, and 25,000 die of starvation every day, they can't afford the food.

Food is just like peak oil, the producers will produce more food if it is profitable and affordable by their customers. If in order to make a profit food prices rise faster than personal incomes peak food will occur - food production is a flow rate, productive agricultural lands are the reserves.

Well, it is certainly true that cheap food has been a mixed blessing for society. Why should something so fundamental be so cheap that those that produce it are always on the ragged edge of financial ruin? It makes no sense, particularly when you look at the sorts of things that the money that is presumably saved on food, gets spent on -- fashionable clothing, electronic gadgetry, tanning sessions and facials, tickets to sporting events, etc. etc. etc.

Still, cheap food makes it possible for those with less to afford to buy food. I am sure that we are heading into a future where food takes a larger bite out of the household budget. That will inevitably mean hunger for the less resourceful.

I appreciate your post, EP. We live in a time of change and it is past time to be rethinking BAU. Still, I can't read it and not think of the social engineers of the 20th century and how their efforts to create a more rational human largely came to naught. Perhaps the agro-technocrats will lead us seamlessly into a lower energy future, but I am skeptical. I've seen enough of human folly and natural disasters to know that things frequently don't go "according to plan."

Your analysis is the one which is faulty. You state a) today, farmers don't make money unless thay are huge ag businesses which can survive on 2 or 3% net including land value, on sales or b) current farmers are not selling energy products instead of food. Facts, granted. Neither one is relevant to a hypothetical future situation in which petroleum energy is non-existent. EP's article captures THAT environment precisely, and to beat him up because he does not describe the present situation perfectly is, at best, an error.


Farmers DON'T make money unless they are huge ag businesses that can survive on 2 - 3% net. The reason there are so many farms taking up the space between suburbs and strip malls is that many people like to grow things and will pay for the opportunity. A wide choice of discresionary part- time incomes has allowed people to divide their efforts between jobs which support the farming.

The larger the farm, the greater the ability to harvest government ag subsidies.

Farmers that are successfully selling energy are laundering Treasury money - which in turn is currently laundering Federal Reserve lending. Without subsidy, there would be very little domestic biofuel production. Money economics here is a proxy for nature's (parsimonious) economics.

That tells me that nature is not so generous as EP would presume.

Energy use/production itself cannot be taken out of context. I personally think that a farmer could produce enough energy to operate his farm without outside energy and still be able to produce crops year after year. I am not a farmer; there is a lot of risk. I don't know if I - as a farmer - would be willing to take the risk of attempting to switch from oil/diesel to some sort of biofuel for for farm operations, particularly without subsidy. It might be necessary at some point, but that point would (logically) be far off in the future.

This 'risk- induced lag' is a constraint on the demand side of the biofuel market.

Here's another risk: the subsidies - and the embedded infrastructure costs - are on the deflation chopping block right now. Currently, there is energy/diesel available. What will happen without the subsidies? This leaves current farmers marooned on an energy island; tethered to a declining model without the means to 'make a switch'.

Ditto w/ the tractor btu model (tractors are mostly made out of cast iron, btw.) The tractor, changes to designs, specs, capabilities, the factories that make them, the materials themselves and the transport for same, the tooling and machinery, the manpower in the factories and the energy budgets of their lives and dependents, the energy costs of the dealers, the transport to the dealers, the buildings themselves that house all of this ... etc, etc. etc. These btu inputs are integral, as are all the downstream energy inputs; the cultivating and harvesting machinery (and their energy inputs), processing, marketing, distributing, packaging, disposing of waste ... all this is a lot of btus.

Don't forget the petro- fertilizers and pesticides; these don't appear by magic or fly to the fields by themslves.

A lot of btus ... the ag sector uses 30% of USA energy for a reason.

The situation here in Canada is significantly different, eg. the govt. offers very few to no direct subsidies to producers, though some indirect and emergency to specific sub-units (presently pork producers are trying to get help). Poultry, eggs and milk are operated in a managed market which restricts supply and keeps prices high enough for producers to make out fairly well if they're good enough. Exporters are essentially on their own, esp. wheat, barley, potatoes etc.

While what you say is generally true ,most of it has little to do with this article.

Ep has not advocated a switch to biofuels at this time,nor has he said that doing so would be profitable.

Nor has he said that farm produced biofuels are a viable solution to our bau woes when the oil dries up.

He did not even claim that farmers can produce enough biofuel to support such industry as is necessary to manufacture enough new trucks and tractors to support the farms and distribute the food produced.

He has crunched the numbers for us and proven that we can produce enough food using biofuels produced by cannibalizing a small portion of current production to get by for a while-probably at least as long as the current generation of machinery lasts.

That's a lot,considering he is donating his time and expertise.


I strongly disagree.

We NEED as many possible backup contingency plans in place as possible in the event of possible fuel shortages.

There is plenty of reason to believe ,given a study of history, that once things get really bad the public can be convinced to embark on a serious program of whatever nature is necessary-rationing, growing victory gardens,fighting wars, eating less , eating down the food chain, etc.

If such stopgaps are not in place , the carnage will be simply indescribable if food is unavailable.-do you want that?

I think we can power down if necessary without starvation and cannibalism.If for some reason ol is suddenly in extremely short supply, we need this capability.

Personally I find it morally repugnant to cavalierly talk about letting people starve for lack of planning .

We must live in the short term in order to do better in the long term.


I'm not sure your comment is addressed to mine but the time indicates that it is.

I made my comment ASSUMING that there will still be some oil,ng, etc available,which should certainly be the case at the time that farmers find it either necessary or cost effective to switch to biofuels.

Personally I don't believe that biofuels will ever support bau but it might be possible to manufacture quite a bit of ESSENTIAL new machinery using recycled steel,aluminum,copper,etc in existing industrial plants.

Furthermore although it is not done regularly because new equipment is cheap,relatively speaking,it is possible to rebuild trucks and tractors for fifty years of constant service.These rebuilds often involve only ten percent new parts such as bearings,pistons,cylinder liners,etc.The really big components such as axles,frames,cabs,transmission housings,engine blocks,etc can usually be used again as is or reconditioned.

A crankshaft for example that is worn past the point that it can be reground "undersize"to functionally new condition (compensated by oversize bearings) can be built up by welding and reground to its original new dimensions.

But over the long run you are more than likely correct-biofuels are not likely to be a permanent answer,especially considered in isolation.

But I have some hope that biofuels in combination with the various other renewables plus the last of the oil,etc, will be sufficient for our grandchildren to enjoy a modern world-even though it likely lack a lot of things we take for granted,like jumping on a plane to go see Grandma or owning a fast car.

This depends of course of a gradual decline in the population-which I trust will take place unless livings standards decline too fast.Well off people tend to have small families.

There are no permanent solutions.I don't think it is possible to see very far into ,except in the most general terms,and I wouldn't even guess what might come to pass in a hundred years.

You seem to have become more of an optimist lately, oldfarmermac. Although I am not an expert, I do know that a large fraction of our fossil fuel consumption is wasted, and a large portion of our agricultural capacity is wasted producing meat which feeds excessive North American consumption. I share your opinion that if FFs do not drop too precipitously, a decent future in North America is possible. Biofuels and electrification cannot do BAU, but can definitely help. In the meantime, foods that are very transportation-intensive (For example, fresh strawberries from Chile) will become a thing of the past, but local growing of these things will increase, especially once people figure out that vegetables and fruits and herbs which are primarily consumed because they taste good taste much better when grown even by a relatively inexperienced backyard gardener.

However, the chances of this occurring are not 100%, and history shows, of course, that the elite will create huge problems in order to protect their power and standards of living. I imagine at some point currency will go all electronic, and by necessity, barter and alternative currency will become illegal. To protect us from the terrorists, pedophiles and drugs of course, which will make things harder, but I suspect that the police state will eventually be forced to contract to focus on protecting the elite.

local growing of these things will increase, especially once people figure out that vegetables and fruits and herbs which are primarily consumed because they taste good taste much better when grown even by a relatively inexperienced backyard gardener.

Amen to that.  My first crop of little yellow tomatoes has just started coming in, and they make salads wonderful!

Incidentally, I found this gem on archaebacterial production of methane from CO2 using only electricity as an energy source.  Efficiency is claimed to be 80%.  If this can be scaled up, production of methane (and perhaps derived products such as methanol) might allow every bit of carbon in e.g. biogas or fermentation off-gas to be converted to fuel using excess wind power.

Even potatoes, which I normally have a hard time telling apart from cardboard, taste much better when you grow them yourself.

As in most edible things, the secret to life....


So? Cardboard would taste pretty good slathered in butter too, if you were hungry.

If this can be scaled up, production of methane (and perhaps derived products such as methanol) might allow every bit of carbon in e.g. biogas or fermentation off-gas to be converted to fuel using excess wind power.

Removing carbon from soil is exactly opposite what sustainable agriculture does.
You know this.
What is the real purpose of your post?

Research has shown that 500 years worth of humified soil carbon, a major indicator of fertility and soil maturation, may be accumulated in as little as eight and a half years(using biointensive methods). Furthermore, this increase in soil carbon may be accomplished by employing a closed system in which a portion of the crop is grown specifically for making compost (Jeavons, 1989).


Removing carbon from soil is exactly opposite what sustainable agriculture does.
You know this.
What is the real purpose of your post?

CO2 coming off fermenting grain, or separated from biogas produced by anaerobic digestion of manure, would never have gone back to the soil anyway.  It's a gas.

The virtue of this CO2 is that it is relatively pure, not diluted in 2600 volumes of air.  If wind-generated electricity can convert it to methane at 80% efficiency, it yields a storable, easily transportable, extremely clean, carbon-neutral fuel without having to grow or process anything that's not already coming off the field.

Precisely why sustainable is the key word here.
Biointensive composting reduces the loss of carbon and nitrogen due to the inclusion of significant portions of soil in the layering.
I personally believe charcoal supplementing or supplanting those soil layers reduces those emissions more but no science yet to back that claim.
Jeavons and crew have demonstrated with his 21 bed minifarm it had to be growing compost crops over 60% of the time just to maintain soil fertility!
The whole notion of farm surplus dwindles when sustainability is recognized.
And that really is the purpose of your post?

It is safe to say that you have utterly missed the purpose of my post, despite it being summarized in the abstract.  If you want to talk about something else, perhaps you should find a different discussion thread.

What I have been patiently trying to explain to you is that the "excess energy" from crops is the crop itself and that everything else must be returned to the soil just to maintain soil fertility.
Your optimistic numbers of what is recoverable from stover, just as erosion control for example, are also whack:

The EPIC model showed that harvesting 40
percent of the corn stover would raise erosion rates
on most soils by 0.25 tons an acre per year.


If the vehicle is a farm tractor or combine which requires 1 gallon-equivalent of energy per acre per pass, of which 90% is coming from fuel gas produced from charcoal...and...If this were used as a natural gas substitute in an ammonia plant, it would suffice to produce roughly 680 pounds of ammonia, containing 560 pounds of nitrogen.

Life must be exceedingly simple in your world.
I hate to be the one to prick the bubble of illusion you are floating in but fertilizers are synthesized from atmospheric nitrogen and natural gas, a process that takes a significant amount of energy. Producing and distributing them requires an average of 5.5 GALLONS of fossil fuels PER ACRE.
Of course, in your world stover is a much more "efficient" substitute than natgas.
And we ain't even getting food to market where we find that studies that do estimate(the energy used in processing and transporting food) that it takes an average of seven to ten calories of input energy to produce one calorie of food.

Your failure to replace the energy removed from the soil is what makes your post worthless.

Lastly you fail at realizing the great distances involved and the fantastic infrastructure in all aspects of food production.
This isn't just about farmer Brown and his dumb tractor.
If the fossil fuel supply becomes disrupted there will be greater disruptions in the availablity of all consumer goods, food especially.

CO2 coming off fermenting grain, or separated from biogas produced by anaerobic digestion of manure, would never have gone back to the soil anyway. It's a gas.

And yet, somehow, a plant is able to grow and Carbon is added to the plant.

I wonder how that happens?

Could it be that Carbon Dioxide from the air is somehow captured?

Your right - the CO2 won't return to the soil. I was not clear enough. My bad.

Course the CO2 isn't "from the soil" - now is it? So how can something 'return' to a point when it did not start from that point? Again - My Bad.

But if that's the height of your techincal argument 'gas is not soil' and your response to someone pointing out that Carbon from CO2 can go back to the soil is not to correct your language but to post a picture just shows that you have a problem with your ego and 'never being wrong'.

My general position all along has been that there will be a substantial collapse of the bau model but that barring losing a war the US will survive the crash and eventually become stable again.But I should probably have said great grand children.

And there is a lot of difference between "some hope" and certainty.;)

Sometimes I do feel much more optimistic- that's just human nature I suppose.

I do expect that there will necessarily be a major movement of people out of some of the larger urban areas into farm country but nothing is certain- with a great deal of luck we might be able to produce enough fuel ,fertilizer and machinery to keep our cities functional-if productive work can be found for the urbanites.

The amount of sunk infrastructure in the cities and suburbs boggles the mind-if we really work at it we could save most of it and still save a huge amount of energy.Probably enough,considering the facy that renewables are coming along well, to maintain something recognizable as bau-minus the automobiles,passenger planes,ski resorts, throwaway junk,of course.

If the average person who could get by without a car were to spend his "car money" on his house he could have a zero energy house he could probably have a near zero energy house in five years for instance.

If we spent as much on rail as we do on passenger air indirectly by not taxing jet fuel we could build one hell of a lot of intercity rail-and the trains don't have to actually go two hundrd mph for rail to work-they only have to go that fast to compete with air travel.

If we taxed advertising and packaging materials ,we could buy more food for a lot less in larger containers.I could go on all day but in the end...the police state is just as likely.

I'm not convinced that we'll be able to produce and operate the next-generation of such machines with only fuels produced on-farm (or without using up all the energy surplus otherwise produced by such farms)...

Emphasis mine. In theory, if the energy surplus otherwise produced by the farms is enough to make the tractors, that's all a sustainable system needs. I agree with you that this is an open question though.

There is also something to be said for making current equipment last as long as possible. As alluded to elsewhere in this thread, the time to replace machines should probably not be based on their replacement rate in the growth economy.

Agreed, and I'm actually fairly optimistic that there will be a significant amount of farm mechanization--even on very small scale farms--well into the future (e.g. the kind of hand-held rototiller that first made Ferrari famous in post-war Italy). Your point that the replacement time-frames we expect in the growth economy will not continue is right on. We'll gradually start considering EROEI over $ROI when making these kinds of decisions, if for no other reason than fiat issues surrounding $ are too far out of the hands of the farmer... when we do that, I think we'll still have some mechanization (for many of the reasons that EP pointed out in his post) and some centralization, but it will be both less and different in nature.

Let's not forget that "fuel" is only one portion of the petroleum products need to run equipment. There are also lubricating oils, hydraulic oils and various greases.

In addition, there are also necessary maintenance parts such as various filters, tires and belts that must be replaced on a regular basis. None of these are likely to be farm produced.

Lastly, it is assumed that the farm or a farm co-op will have the necessary equipment to press oils and fabricate equipment.

Compared to animals, "equipment" requires a significant, functioning infrastructure.


I'd beg to differ.

Animals require constant upkeep. Domestic horses must be shod, harnesses need to be manufactured and maintained, sickness and injuries need to be dealt with.

A community is necessary no matter what.

Many of the current imports are just better than what can be produced in a small community, not completely irreplacable. Filters can certainly be locally produced and periodically cleaned instead of replaced whenever they are dirty. Belts can be made from locally available materials. Many older tractors had metal lugs around the rim instead of rubber tires.

I'd say that considerable infrastructure is necessary to maintain a business of any type, including a farm, and the size of the business that can be supported is going to be dependent on the quality of the infrastructure.

Belts used to be leather straps made continuous by metal clips that joined the ends running on flat pulleys, air filters used to be oil-covered metal "mesh" and spark was generated by magnetos, no battery needed. Granted those were simple low horsepower tractors and that technology wouldn't work well on current 200 horse John Deere's. Return to more locally sustainable technology is certainly possible but that will be driven by the relative costs and benefits of local vs. remote.

Used to be important enough there was a "Institute of Leather Technology" at the Milwaukee School of Engineering.

Dedicated in 1961

Assuming seeding, harvesting and 3 other passes per year, the total comes to approximately 750 MJ per acre per year. Nitrogen fertilizer applied at 200 pounds of nitrogen per acre would account for another 4600 MJ per acre1.

So the Haber process adds over 6 times to the energy requirements?
The picture is coming into focus--

"So the Haber process adds over 6 times to the energy requirements?
The picture is coming into focus--"

Unfortunately, global pop. has ramped six times too.

I am assuming 4600 MJ per acre is just for ammonia or urea, N-products. But many of the various types of mfg. ferts are I-NPK, plus trace nutrients, with a whole hell of a lot of S to beneficiate the P to quick soil activation. Research may show that this 4600 MJ may need to be doubled again to fully account for the P,K and other trace Elements required to avert a Liebig Minimum.

The other major problem is moving I-NPK from point of mining or mfg. to the final sq. foot of topsoil. I have posted a prior link where the seaport cost of I-NPK in Africa may go up SIX TIMES or more as it gets moved over poor transport infrastructure, then finally backpacked inside the farmgate. Picture moving a 50 lb bag of I-NPK to the high farm slopes of Mt. Kilimanjaro.

Amazingly, the WFP has been in Nepal for 45 years, yet cannot seem to grasp these above concepts. I have posted earlier a weblink on dire food security in this mountainous country [or google for yourself].
IMO, it provides a cautionary tale for non-organic 'Murkan farmers, permaculturists, and gardeners far from a seaport and/or rail depot. The logistics of moving bulk far-inland and to high altitudes is fixed by Physics until someone invents the Star Trek Transporter to beam items energy-free [highly doubtful].

Bob Shaw in Phx,Az Are Humans Smarter than Yeast?

A good, early example of the above concepts may be golf courses in the Rockies going belly up. A ship full of I-NPKS in Houston or New Orleans may offer cheap, imported ferts from Russia/Morocco/Trinidad, but the golf course owners can't afford the extra transport cost to get it moved to their greens and fairways. A farmer, with land adjacent to the Mississippi ten miles from New Orleans, can get the goods much cheaper because logistics are on his side relative to a golf course in the Tetons, for example. He just requires a short upriver barge to fulfill his I-NPK needs.

I agree that the US is unlikely to be so short of fuel as to seriously curtail agricultural production. But I can still see three possible future issues that results in large numbers of US citizens going hungry.

1. Financial collapse/depression.
People lose their jobs in huge numbers. Welfare is overwhelmed, the state cannot provide (real) money. People go hungry as food is exported in large quantities to pay off US debts.

2. The fuel for agricultural production is a lot less than the fuel used in distribution. If fuel gets short, poor areas with little local production find food hard to come by. Localised hunger.

3. The road infrastructure decays rapidly due to lack of maintenance. Bridges collapse. Roads become impassible. Food distribution becomes impractical. Food rots in the fields. This happened a lot in FSU countries.

0. Pure Frie(dman) markets marginalizing the poor.

I suggest we look at the big picture with regard to energy inputs vs. output (the following is for example only);

Excellent chart!

And what pray do you see? Hehe..

This article discusses technical possibility not a realistic future scenario. If we tackle the more difficult aspects before crisis this envisioned future could come to pass. There is nothing in our historical record to believe we are on a sustainable course. Good theories with no action are as bad as poorly thought out actions.

So, to maintain the optimistic perspective, please post a follow-up article discussing actual integration of the above theoretical possibilities. In the absence of positive action, pessimism is warranted.

And remember, everything in the above post existed for the past 20 years with very little progress. Starving people in many countries could use the above proposed actions to maintain their lives, and yet thousands upon thousands starve every day in every region of the world. Haiti is real. Utopia is not. Strive for utopia, yes, but prepare for the worst.

Even so, as a budding farmer, I appreciate the analysis for my personal preparations. I am just not optimistic that similar actions will allow most others to survive.

Cold Camel

TOD constantly reminds me of the saying 'Never be a pessimist - pessimists are usually right, but optimists have more fun'. In my late middle age I remain a pessimist and yet somehow I'm having more fun now than before. I grin and sing along to Laughing Lenny Cohen - 'Everybody Knows'.

Comparison to Haiti would be appropriate if Haiti depended on mechanized agriculture, which it does not.

Haiti's problems can't be solved absent a substantial population cut and radically reduced pressure on forests.  Contraception and substitution of solar ovens and gobar gas for charcoal can get at least partway there, but the collective intelligence to use them appears to be lacking.  The USA's situation is not at all comparable to Haiti... at least, not yet.  Continued high immigration will eventually bring that about, which is why any lasting solution to the USA's problems has to include near-zero net immigration.  The recent departure of many illegal aliens due to the recession isn't a bad start.

"The recent departure of many illegal aliens due to the recession isn't a bad start."

That stream of humanity may be turning around the other way soon as Cantarell goes belly up:

A third of Mexicans would migrate to U.S.: survey

You don't need to tell me that we need a border fence, universal E-Verify and deportation of any illegals caught anywhere for any reason.

So you agree that your model doesn't work for everybody worldwide. Others will be left to rot. Your perspective and mine only differ by degree. I suggest the line will be drawn closer to home.

Mechanical agriculture has tremendous productivity advantages, but if society fails, farmers dependent upon external input will become unable to produce. Nearly self-dependent animal agriculture farmers could continue to produce for a few years of chaos, feeding neighboring communities. For example, compare Germany after WWI and WWII. Farmers maintained animals through WWI, but after WWII everyone nearly starved.

Self-sufficient animal agriculture isn't really an option either because it doesn't exist anywhere stable governments have persisted. Not even the Amish are self-sufficient to any extent any more. But it is an option for small communities.

I have competent neighbors who lack foresight. If I provide assets they will sorely need, we'll all do much better. We won't be self-sufficient, but if we can provide for ourselves for 3-5 years while things sort out, our kids won't become statistics. We'll live in WWI Germany while everybody else has to struggle through WWII Germany, or Haiti, or whatever. That's the plan anyway. Ideally we'll be turnkey, still engaged in the greater society but ready to unplug. They don't even need to know.

Once again I'll ask, where has your theory become actual practice? If it doesn't exist anywhere today, it's not real. Show me your cards. Mine? Read Wisdom from Pakistan's posts. He lives it.

Cold Camel

So you agree that your model doesn't work for everybody worldwide. Others will be left to rot.

What do you mean, "left to rot"?  They have their own countries, and need to learn how to make things work there.  We have our country, and need to learn how to make things work here.  Flooding the USA with another population surge just as shrinking capacities have to be carefully re-allocated is a recipe for civil war when conflict means utter failure.  Doing that means WE will rot.  If compassion means suicide, you can call me hard-hearted and I'll laugh at you.  By that definition, only the hard-hearted will live.

Mexico has a long agrarian tradition that is still going.  There is no reason that it can't revive it and be successful.  They should get started there, while we get started here looking for something that works for us.

Others who post on TOD care about humans equally. They suggest we should "do" something to help others in other countries. Clearly you do not share these views, and neither do I. The fact that we distinguish between "us" and "them" makes us more alike than not.

But we still view things very differently. Anyone who talks about what "we" must do wields a gun. That you restrict your definition of "we" to U.S. citizens makes you no less evil than others who want one-world-nation. Liberty. Leave me to feed mine, you feed yours.

I'm not arguing E-P. I know I have a minority view. I'm not trying to change minds. I'd rather fade away and be ignored. As decline occurs, your view will gain precedence. As it continues there will be a significant possibility that resource decline will cause the U.S. to lose domestic integrity, at which point society will break down. I intend to make it through the squeeze. If I am wrong, I'll be poorer, that's all.

Since you haven't replied to my requests for evidence of applied actions, I assume you don't have any. Your system is too complex for me and my neighbors, but I can well imagine animal agriculture. I'll give up productivity since I don't need to get rich or feed strangers. As you put it:

(The rest of the U.S.) has a long agrarian tradition that is still going. There is no reason that it can't revive it and be successful.

Cold Camel

I'm with you CC. I don't care for nationalism or borders. We're all citizens of the world, and should be free to come & go, to live & work, where we please. Border fences are stupid, & impede the movements of animals across their ranges. I welcome my Spanish speaking brothers here in New Mexico. The entire US Southwest was stolen from Mexico in the first place. Open the borders, I say. I like Mexico, maybe I'd move there if politics got out of the way.


Some days you are a biologist and some days you aren't-today you are a fine human being but I have question for DD the biologist-who did your SPANISH speaking Mexican brothers steal the southwest from?

Do you think that this process of conquest is natural?

If not what are it's unnatural origins?

Personally I like my Spanish speaking nieghbors just fine but I am not anxious to see the country more densely populated than it is now.

The idea of having no borders is nice in the abstract but the realities?

As some conservative sage once said,I 'd rather be governed by the first five hundred names in the phone book than the faculty of Harvard University.

There's an interesting book you might be interested in Mac: "Cycles of Conquest," 1962 by Spicer. It details how Na-Dene speaking peoples stole the Southwest from Amerind speakers, only to have it stole from them in turn by the Spanish, Mexicans, "Anglo" Americans.


Thanks! I'll put this one on my list -since I 've been reading this site I have accumulated quite a list-about a hundred books I want already.That should hold me for about two years,given my current circumstances.

My guess is that the Spanish/Mexicans will for all intents and purposes finish retaking this territory with hardly a shot fired within a couple more generations.

The current population of Spanish people in this country is already large enough that niether party can afford in the short term to make any serious moves toward closing the border for fear of losing elections if they decide to vote in a bloc for the other party. And the short term is of course everything in electoral politics.

Furthermore there is a strong but not much publicized argument to be made that we need a lot of healthy young immigrants to support the boomers retirement.I'd personally rather get by with a little less help from the great chief in Washington.

(Our only real hope is a falling birth rate.)

And of course the eventual consequences of the increased population is just one more problen for our grandchildren.

The "healthy young immigrants" we're getting are overwhelmingly low-skilled, a large majority of whom do not have a high-school diploma.  They make low wages, and after the earned-income tax credit they pay almost no Social Security taxes.  Because they make low incomes, their eventual Social Security benefits are subsidized compared to those of higher earners.  In other words, these immigrants are a slow-motion disaster for Social Security as well as everything else (except the cheap-labor businesses and pols whose votes come from the low-income strata).


I agree. You will notice that I didn't say I agree with the argument but I did fail to make it clear that I meant many others do agree and will support immigration uncritically in hopes of collecting from the various entitlement programs by piling taxes on the backs of the newcomers.

During WWI there was a blockade of Germany and 600,000 starved to death.

I stand corrected.

Thanks for mentioning external combustion (steam powered) engines. We tend to forget about those around here. Yes, they are relatively inefficient, and not the top choice in a best case situation. However, we should keep in mind that these were built with relatively low technology in the early 18th century. There are enough tools and industrial-era artifacts and junk scattered around that it should be possible for people with a little time, a little know-how, and a little work to get an old steam engine running again, or fabricate a new one. No point doing this as long as ICE engines are an option. However, should things ever get to the point where ICE engines are no longer feasible, then it should be remembered that steam engines burning biomass of one type or another are an option. Given the choice between starving to death and rigging up equipment powered by a homebrew steam engine, I'll bet that most communities will choose the steam engine. They will not, of course, be able to sustain anything even remotely close to BAU; we are only talking about hitting the brakes on the descent someplace.

Steam engines are not the only external combustion engines. Stirling engines combine reasonable efficiency with external combustion. They can run on almost any fuel and have fewer moving parts than an ICE. No valves. Models can run on a cup of tea or even a warm hand.

Stirling engine tractors are not currently available, but stationary engines are.

I've heard enough about stirling engines to supply my personal energy needs forever if I could capture all the hot air.

Apparently the only way to build one that actually produces a useful amount of power is to build it out of gold and platinum with diamond trim and stick one end of it in an erupting volcano.

When does anybody here actually expect to see a working stirling on a farm or at a small business?

I do know they have been deployed at cst power plants but the temperatures achieved by those big mirrors on the hot end and the few details available about them make them look about as practical as owning your own nuke.

I would be more than happy for an engineer who has actual experience with stirlings to set me straight.

Well.... I just lost my shirt investing in a novel configuration stirling (which I designed, so no-one to blame even. missed one item of parasitic losses in the thermal equations, and of course that was the one which was critical. nuts), if that qualifies me for an opinion. In general you're right. Stirlings suffer from the same weakness as turbines, which is that the heated surface is continuously exposed to the high temperature, meaning either the engine gets very expensive per unit power or the efficiency gets so low the engine is not much use. High-effic. turbines need extremely costly power turbine blading and combustion chambers, and very high precision clearances. IC otto and diesel engines get high effic. from cheap materials because high temps only exist for less than 25% time against exposed metal surfaces.

Big air-fluid low-temp stirlings have been used for decades as irrigation pump drivers in India, because they're simple and burn straw. Not efficient enough to be much use given ANY alternative except animal power.

Stirling designs have a lot of potential yet, but need a manufacturing breakthrough in the fabrication of precision complex parts from ceramics like silicon carbide at low cost. When / if we ever get there, then a lot of things might should change.

but stationary engines are.

Where can one buy a mass produced stationary stirling that is a 1+hp unit?

You could try Infinia, makes a real sweetie 1 kw engine-generator designed to be fueled with natural gas. 25% efficiency, sealed engine should run mtce-free for > 80,000 hrs. Or WhisperGen in New Zealand, many dealers eg. TotalPower, a WhisperGen dealer in Ontario, Canada. Similar specs to above. Be prepared for serious prices though.

Whipsergen - $10,000. USed to be $30,000.

Infinia - now goes to Enatec. On the English page

This cooperation will lead to mass production and sales of micro CHP systems in Europe as from 2009.

But lets see what archive.org says

When will the unit be available to the consumer?
It is the intention that the first units will be available for early adopters in 2003. ATAG Verwarming predicts a large-scale market introduction in 2004.


And I'd bet if I come back in 2010, none will have shipped and the web page will be updated to reflect a 2010 ship date.

It looks like Enatec changed manufacturing partners in 2004. I'm sure there's a story there.

The Whispergen units have been shipping for quite some time, and look like a nice product.

Having spent many hours over many months chasing Stirling CHP systems, I've come to the conclusion that, unless someone can show me a working unit one can buy for cash on the table money, Stirling CHP are just a promise.

It looks like they are more than a promise in Europe and Canada, but of course that doesn't mean you can get them easily (or at all) wherever you are.

International trade, building codes, and certification programs conspire together to foil would-be leading edge technology users the world over.

It looks like they are more than a promise in Europe and Canada

Really? Based on what?

They claim 'mass production' in 2009. They've claimed mass production on other dates like 2004.

Whispergen is a European company too, with a Canadian distributor that at least claims 2K installations.

Don't you read the links?

Bio-oil, unlike ethanol, cannot be used in IC engines.
It can be burnt in boilers and other engines.

It has been burnt in external combustion Stirling engines but at low efficiency(50% of IC engines).

Bio-oil can be upgraded by F+T methods with an energy penalty.
The obvious path is to take bio-oil to the oil refinery and to upgrade it their but that doesn't represent self-sustaining agriculture.

Best bet, IMO is cellulosic ethanol in diesel(compression ignition) engines which is currently done in buses in Sweden and Brazil.


I don't see ICE farming being "Sustainable"

maybe this ..



How many acres to support a 'Working Draft Animal" ? 5 acres??

how many calories per day ?


15,000 calories ??


Organic Farmer .. class of 67, College of Agriculture - CSUF

"Bio-oil, unlike ethanol, cannot be used in IC engines."

That sure is news to these guys:


Do you want to break the bad news to them, or should I?

Bio-oil is not bio-diesel.

Bio-oil is made by pyrolysis of biomass.

Bio-diesel is made by extracting vegetable oil from certain plants using solvents and treating them with chemicals.

Only a small bit of the plant(seeds, fruit) is processed into fuel whereas in bo-oul the entire plant is used.

I should probably take E-P's advice below, but what the hell, I'm bored so here goes:

Why are you talking about bio-diesel? I didn't say anything about bio-diesel, both links were about using straight vegetable oil (SVO) in diesel engines.

Is "Bio-oil" an industry accepted term for oil products produced by pyrolysis? My definition of bio-oil would be something like "oil produced from biological feed stocks", so vegetable oil, lard, butter, algae oil, etc. would all be bio-oils. If I had known how you were using the term, I would have responded differently, if at all.

Your statement "Bio-diesel is made by extracting vegetable oil from certain plants using solvents and treating them with chemicals." is only partial correct. Bio-diesel can be produced from any bio-oil (my definition), not just from certain plant oils.

"Bio-oil (Figure 1) is the liquid condensate of the vapors of a pyrolysis reaction."




Bio-diesel can be produced from any bio-oil (my definition), not just from certain plant oils.

Biodiesel CANNOT be made from any bio-oil.

What is wrong with you?

The pdf link you provided also says this: "The latter comprises condensable vapors called pyrolysis oil (also known as bio-oil, biocrude, etc.)". It seems the proper term is 'pyrolysis oil', while the others would be considered slang.

The Wikipedia link *you* provided clearly show that the product you are talking about is properly called 'pyrolysis oil'. The Wikipedia entry is titled 'Pyrolysis oil', NOT 'bio-oil'! Only later in the entry do they even use the term bio-oil, and it is clearly being used as a broad descriptor, not as a proper noun. Did you even read the entry you linked?

Again, from the other link you provided:

"A variety of oils can be used to produce biodiesel. These include:
* Virgin oil feedstock; rapeseed and soybean oils are most commonly used, soybean oil alone accounting for about ninety percent of all fuel stocks in the US. It also can be obtained from field pennycress and jatropha and other crops such as mustard, flax, sunflower, palm oil, coconut, hemp (see List of vegetable oils for more information);
* Waste vegetable oil (WVO);
* Animal fats including tallow, lard, yellow grease, chicken fat,[41] and the by-products of the production of Omega-3 fatty acids from fish oil.
* Algae, which can be grown using waste materials such as sewage[42] and without displacing land currently used for food production.
* Oil from halophytes such as salicornia bigelovii, which can be grown using saltwater in coastal areas where conventional crops cannot be grown, with yields equal to the yields of soybeans and other oilseeds grown using freshwater irrigation[43]"

(Please note that this Wikipedia entry is NOT all-inclusive.)
Perhaps I should have used the word 'virtually' before 'any' in my post, just to cover my ass, but it's clear that my statement is closer to the truth than your original one is.

Now you're just being an ass, Egg-on

"What Is Bio-Oil?
Bio-oil (Figure 1) is the liquid condensate of the vapors of a pyrolysis reaction. It is a dark brownish viscous liquid that bears some resemblance to fossil crude oil."

I gave you a definition and you pretend that bio-oil isn't a well understood term.

But in a fuller sense, you're missing the whole point.

Biodiesel refers to a method of producing fuel by means of trans-esterfication. The feedstock generally is the fruit or seed(which is food for humans) where the plant concentrates all the chemical energy.

You could make biodiesel out of corn (oil) but it wouldn't be very productive per acre.

Bio-oil refers to the condensation of vapors produced by the the break down of feedstock burning(pyrolsis) in low oxygen conditions.

So much for an honest discussion of bio-oil versus biodiesel.

Algae as a source of biodiesel(transesterfication) is extremely promising.

Open pond systems have largely failed because the high lipid algae get infected easily and die massively.

New system have the algae grown in closed photobioreactors with CO2 pumped in. I think this will become very big in the next 5 years.


Well, I say you are both wrong, Bio-Oil is a beauty product.

You never gave me a "definition of bio-oil". You gave references to colloquial use of the phrase in discussions of pyrolysis oil. I do not "pretend that bio-oil isn't a well understood term", I do dispute your assertions that the definition of the term 'bio-oil' is 'pyrolysis oil'.

In a MUCH fuller sense, YOU are missing the whole point: We never entered into "an honest discussion of bio-oil versus biodiesel" in the first place.

My apologies to Engineer-Poet - I should have followed your advice, and will do so starting now.

Don't try arguing with majorian.  You can show him that pyrolysis oil can be converted to syngas (a gasogene starting with liquid instead of solid fuel) and fumigated like any gaseous fuel, and his response will be predictably obtuse and emotional.

There's a link for flagging teh stoopid.  I suggest using it.

You do know what the word 'fumigate' means, right E-P?

"to apply smoke, vapor, or gas especially for the purpose of disinfecting or of destroying pests"



"The gasogene (or seltzogene) was a late Victorian device for producing carbonated water."


You are TOO kewl, E-P.

Propane fumigation in diesel engines

Gasogene: "(materials) A fuel gas formed by incomplete combustion of charcoal; a European development as a substitute for gasoline."

From your quoted definition: "to apply smoke, vapor, or gas"
That's exactly what is going on. The definition says "especially for the purpose of disinfecting or of destroying pests", not "only for the purpose of disinfecting or of destroying pests".

From your Gasogene link:
"For the automotive device, see Wood gas generator."

Even Wikipedia knows what it is, they just have it filed elsewhere.

For goodness sake man, can't you even be pedantic properly?

Incidentally, when I use that image above it means I flagged the parent.  It beats lots of replies to trolls.

I've got a book around someplace that details the use of a ninety horsepower Duetz diesel at a sawmill somewhere up near the artic circle in Scandanavia that has been driving a generator and thus powering an electrified sawmill plus supplying electric power for the little village of mill workers since sometime in the seventies iirc.

It runs on wood waste processed thru a site built gasifier and uses only a tiny bit of diesel for ignition.

If you search wood gasifier and sawmill and duetz you get a link thru the UN FAO (united nations food and agriculture organization) but it doesn't work.I have a hard copy someplace-one of these days I'll straighten up.

Languages change.Thats why the dictionary has more than one entry-ughh! ughh!! ughh!!

You can show him that pyrolysis oil can be converted to syngas (a gasogene starting with liquid instead of solid fuel) and fumigated like any gaseous fuel, and his response will be predictably obtuse and emotional.

So based on your interpretation what E-P means is that
is a gas, smoke or vapor applied like any gaseous fuel rather than syngas is applied for the purpose of disinfecting or destroying pests.

I think that's probably what E-P means but who can say?

But it's rather tautological is it not?(a syngas fuel is applied like a gas fuel)
except he's taking about pyrolysis oil which is not turned into a gas but is burnt as a liquid. I suppose diamonds could be gasified to make liquid fuel but it would be silly to do so, even for E-P.

His link of a propane fumigator is to a Mr. Sharkey's blog,
so E-P must be using the word 'fumigate' correctly.

E-P seems to believe it is easy to run engines on syngas and here I can help him out.

ENERGY RESOURCE-18 September 2006-First Successful Operation of Syngas-Powered Engine Generator Announced(C)2006 JeraOne - http://www.jeraone.com

Synthesis Energy Systems Inc. and Quantum Fuel Systems Technologies Worldwide Inc. today announced the successful operation of the world's first engine generator using synthesis gas, or "syngas," as fuel.


BTW, the wikipedia entry doesn't mention fumigating except in terms of pest control.

Gasogene isn't actual mentioned anywhere in the Wood gas generator wiki you point out, r4
so I would say it is one of those anachronistic terms favored by the Poetical Troll.

It is however mentioned in Sherlock Holmes stories, which must have lodged in his wide-ranging intellect.

The gasogene features as a cryptic residential fixture at 221B Baker Street in Arthur Conan Doyle's Sherlock Holmes stories.


You're definitely wrong to believe that bit of PR hype about "first syngas engine". Maybe they're using a very strict definition of syngas, or they're just pulling in credulous reporters. (All I get following your link is an advert trying to sell me the domain name)

Wood-fired cars and tractors did practically all farming in the Scandanavian countries during WWII. I've also read accounts of a guy who's been driving his pickup truck allover Australia for years fueled only with a wood-fueled gassifier in the truck bed. Bio-mass gassifier technology has been known and widely used for decades at least.

And the US war department had info about doing such 'for the war effort' and I believe the present DOD still has such as part of their planning.

There are several listservs dealing with woodgas, which is what I take gasogene to be. I will post the links I have for various woodgas sites and a pdf of the 1989 FEMA document for construction of a woodgas generator capable of powering a tractor or other ICE engine using parts that the average farmer or mechanic would have lying around the farm/shop. It'll have to be tomorrow morning it's late and I have to get the soot off and go to bed. Nitey nite

Thank you, Rob! I really appreciate you posting those links as I was not able to get to it in a timely fashion.

Re: the FEMA device, is it a tar producer even with the filtration component? I haven't built one yet, but I use an HS Tarm wood-gasifying boiler to heat all our domestic water year-round and for baseboard heat during the winter. The system uses a 600 gallon water tank as a heat storage medium, so I only have to fire the boiler up once every four days, for about 6 hours, in the summer for all hot water needs. In the winter I fire it every other day except when it gets really cold (less than 10 deg F) or really windy and then I might fore it every day. When it is in wood gas mode it produces no smoke, unlike outdoor boilers. We haven't used any propane for heat or hot water for over 3 1/2 years. We are entering the heating season this year with about 1/2 cord left from last year to begin the new, meaning we burned about somewhere around 9 or 10 cords for all heat and hot water for a year in 2 woodstoves and the boiler.

Before self-powered farm machinery, there were draft animals. They were slow to reproduce ...

Farm animals may be 'slow' to reproduce, but draught animals do reproduce themselves, unlike tractors. Expensive machinery leads to hi-debt farming.

One of the elements of "crash" scenarios is that mechanized agriculture fails due to lack of fuel before draft animals can be bred to do the work.  If the fuel (not parts, etc.) needs of machinery can be met from the farm itself, that problem becomes long-term rather than immediate.

This is entirely feasible. While horse reproduction rates can be significant over many years, draught animals would not be available in sufficient quantities in the event of a crash or collapse.

Horses at least wouldn't be available in large numbers, but there's 96 million head of cattle in the US. Training would be the biggest holdup if they were needed in a hurry.

Broodmares are used by the Amish for field work, even when pregnant. I talked to some Amish who would work them right up to the point that they gave birth, albeit not the hardest work (deep plowing).

A mare can start reproducing at 5 years to about 21, or at least 16 years or 8 foals.



At one foal every 2 years (assuming a 50% reproduction rate), after 50 years, one mare can be the progenitor of over 100 horses.

And the broodmare works in the field with her foal tethered alongside, or the foal is nourished during work breaks.

How long until PETA finds out about the practice and forces a halt?

They've had over a century and haven't had an issue yet, so I don't expect them to get in the way during powerdown...

The mare looks to be in good condition and the foal looks to be almost a new born.

Say what you want about horses but they have proven they can get the job done.

Self-sustaining systems often look good on paper or even in computer models. Anybody remember Biosphere 2? Looked feasible but didn't play out. A farm might be a much more tractable problem than a whole biome, but there is only one way to really know.

What I would love to see is a set of prototypes, actual farms set up to run on different biofuel scenarios with full instrumentation of soils, imports and exports, etc. That is the best way to evaluate these ideas and start to move toward sustainable agriculture. The other thing we should be able to learn from this would be how many people can be supported (food-wise) per hectare. That would be an important determinant in a lot of future (possibly sooner than latter) policy development.

Question Everything

Indeed, all of this should be tested and shaken out starting now.  USDA's wood gasifier project didn't wait for the 70's oil crisis to escalate to an acute shortage of tractor fuel, and neither should this.  Plans, installation instructions and software hacks should all be developed post haste; ideally, CNC machining instructions for kit components should be developed for common shop tools.

It's coming together now EP. Open source CNC plans are at the first link
Forums and much info here
Write up in current Farm Show magazine here

Europeans have good info available here


That's the gasifier, for a relatively small engine at that.  The plumbing to get the gas into an engine (particularly the venturi systems for induction with low inlet pressure drop) is something that needs to be developed for common vehicle models, along with the other mechanical, electronic and software tweaks to make it work well.

The last lister importer I know of stopped because of EPA regs on emissions.

So I'm not sure the engines featured on those pages can be obtained.

I think your figures of 3-4 horses to plow 2.5 acres/day are a bit off. An acre was originally defined as the land area plowable by one ox in a day; the rule of thumb remains one acre per animal per day, so a team of 3-4 horses should be able to manage 3-4 acres per day.

Often neglected in such articles is the value of soil carbon, both for sequestration from the atmosphere as well as providing a storage medium for numerous nutrients, namely water and nitrogen. Start to remove the "waste" crop residues, and production will decline, certainly without the application of external nitrogen and irrigation (thus even more energy required).

And a third point... fallow land is hardly unproductive. Land outside of crop production -- pasture land in particular -- is recharging nutrient stores. The growth difference between planting worn out crop land vs. land returned from a fallow state can be quite dramatic.

Often neglected.. is the value of soil carbon, both for sequestration.. as well as providing a storage medium for numerous nutrients, namely water and nitrogen. Start to remove the "waste" crop residues, and production will decline..

And a third point... fallow land is hardly unproductive. Land outside of crop production -- pasture land in particular -- is recharging nutrient stores.

Words of wisdom davidveale.

I'm not trying to be argumentative: this just reflects my lack of knowledge on the topic. I'm pretty sure I'm being overly reductive, but I've wondered this for a long time.

If crop ash and all manures were returned to the field, and a portion of the biomass were pyrolized to biochar, could the field maintain fertility? If the only thing removed from the field were hydrocarbon compounds, wouldn't everything else remain in equilibrium?

If the only thing removed from the field were hydrocarbon compounds, we'd get no amino acids or phospholipids or nucleotides in our diet. Theoretically, these compounds, or their elemental constituents, could be returned to the fields if all manures including urine were returned along with ash. Even if this was practicable, however, soil structure & microbial activity would diminish from lack of ligno-cellulosic return & decomposition. As for biochar, I'm not convinced that it's a good idea. I'm no authority on the subject so I may be wrong but I think that return of refractile organic compounds is better for soil health than return in the form of inert charcoal.

The figures I have for corn stover productivity state that it is the excess over the quantity needed for erosion control, so the soil is covered:  "Estimating 60% as corn stover's upper collection limit appears to be conservative due to its broad leaves and high quantity per acre".  Also, you will also have the stubble and the entire below-ground mass of the plant left for the decomposers.

I am suddenly struck by the idea of using ammonium carbonate as a binder for ash particles, the same way Eprida uses it as a binder for biochar.  It could even be drilled into the ground rather than broadcast.  Let the soil fauna distribute the solid matter around after the nitrogen has been taken up.

Biochar appears to do things that organic soil compounds can't, so this probably isn't an either/or option.

Very confusing.
Are you ill?
dd's post never once mentioned erosion control.
Also above you propose using the charcoal as fuel, so whats this talk of biochar?
You can't have it both ways.

Very confusing.
Are you ill?
dd's post never once mentioned erosion control.

The paper I referenced does, albeit obliquely.  If it wasn't mentioned, someone would have been certain to bring it up.  Do try to follow along.

Also above you propose using the charcoal as fuel, so whats this talk of biochar?
You can't have it both ways.

If the crop produces more stover than is needed for fuel (which the 1.7 million BTU/ac demand vs. the ~26 million BTU/ac supply suggests), the excess can be used for anything else desired.  The production of biochar itself yields heat and combustible gas, so it is possible that other uses on the farm may create more biochar than is needed to power equipment.  The excess can be used as a long-lived store of carbon in the soil.

The production of biochar itself yields heat and combustible gas, so it is possible that other uses on the farm may create more biochar than is needed to power equipment.

On the contrary, the reduction in volume of pyrolized material is conservatatively 2/3's the original leaving you a 1/3, plus the pyrolization process requires fuel, unless one develops a solar furnace similar to Scott Bidstrups' proposal. Then of course you are limited by the solar cycles and weather, significant factors in most of the prime growing areas of this country.

The way you try to splice unrelated facts and your attempt at getting dual results from one process in order to prove your argument is what is difficult to follow.

EDIT Snarky comment deleted.

the reduction in volume of pyrolized material is conservatatively 2/3's the original leaving you a 1/3

You appear to have no grasp of the article itself, which refers to energy content, not volume.  Charcoal has more energy per unit mass than lignocellulose, as most of the oxygen is removed; 30% of the mass has about 50% of the energy.  If you can't follow the physics, you shouldn't be trying to critique.

pyrolization process requires fuel

Person who claims something is impossible should get out of the way of person who is doing it:

Research at the University of Hawaii (UH) has led to the discovery of the Flash Carbonization™ process that quickly and efficiently produces biocarbon (i.e., charcoal) from biomass. This process involves the ignition of a flash fire at elevated pressure in a packed bed of biomass. Because of the elevated pressure, the fire quickly spreads through the bed, triggering the transformation of biomass to biocarbon.
We are now testing a commercial-scale, stand-alone (off-the-grid) Flash Carbonization™ Demonstration Reactor ("Demo Reactor"). The first successful test of the Demo Reactor occurred on 24 November 2006. A canister full of corn cobs was carbonized in less than 30 min.

The production of charcoal has traditionally been done using heat supplied by partial combustion of the material itself; this is just a more efficient process.  You should know better than to make nonsensical claims, especially when the contrary is widely accepted and non-controversial.

"You appear to have no grasp of the article itself, which refers to energy content, not volume. "
Yes it does matter.
If charcoal is to be added to the soil as an ammendment as you claim it needs at least 10% by volume to see benefits.
My own experience tells me 30-40% is an ideal ratio.

"The production of charcoal has traditionally been done using heat supplied by partial combustion of the material itself; this is just a more efficient process."

If the pyrolitic gases are used for the pyrolisis as in a retort, there will be little available as oil and the "traditional" method of using the target material is the LEAST efficient in terms of yield.
Of course the "Flash Carbonization" process you link to(which isn't described well but alludes to hi-tech and/or exotic materials) would be magically made available to farmers hither and yon even during a "fast crash doom scenario"?
No wonder your article is ungraspable, it conveniently rejects reality and inserts your optimism.

"Person who claims something is impossible should get out of the way of person who is doing it"
Upthread you claim success with your very first tomato plant, congratulations.
I have been growing a significant percentage of my own diet organically for 20+ years and no longer have illusions about onsite sustainability.
All of my gasoline usage IRT my garden is used to gather imported material(leaves, straw) for my compost and wood for my stove whose byproducts (branches, bark) I have been converting into charcoal using retorts I have designed myself.
No mechanized farm can see to all its own energy needs.
THAT is what you have proved with your article.

I think these ideas are unrealistic and underestimate the time, backbreaking effort and off-farm inputs needed. The net energy is too low and modern humans are not mentally and physically conditioned for such work. This is based on experience of
1) draft horse breeding, specifically Percheron-thoroughbred cross horses
2) driving around on 80% home made biodiesel for the last 5 years
3) growing hay on rich soil in 1500mm (60") rainfall country.

I agree that local fuel production for farm vehicles represents a Holy Grail. However I think that we should pursue alternatives like farming on gantries (tracked vehicles) or preferential allocation of dwindling fuel supplies. I doubt that steam powered ECE or wood gas burning ICE farm vehicles will be practical. Biomethane will produce low net energy after the effort required for bulk materials handling, gas scrubbing and compression.

For large agricultural machinery I think we should pursue compressed natural or synthetic gas when there are no liquid fuels left. The gas could be delivered to the farm by truck and stored in 220 bar tanks. Farm tractors will fill their smaller tanks from this large mother tank. To guarantee longevity of supply the use of natural gas in electrical generation should be discouraged. For example gas used for stationary generation could be taxed heavily while NG for agricultural applications is untaxed.

If things do have to switch to 220 bar tanks (and the tankage can be forged quickly enough, and farmers can afford it), I would expect the gas to be created at the farm itself.  If the claims of 60+% conversion of lignocellulose in anaerobic digesters are correct, the efficiency is more than sufficient to get the job done.  The price of a compressor would eliminate the need to ship gas in inefficient trucks.  Cleanup such as removing CO2 can be done by bubbling compressed gas at ~100 PSIG through a water column, followed by drying.  The energy to compress the gas could come from wind power or an engine running on biogas.

In a crisis, I expect people to make do with what they have on hand or can convert from available materials.  I don't see large stocks of spare 220 bar tanks out there; the oxygen cylinder on the welding rig isn't big enough, and is more valuable where it is.

Boof wrote: For large agricultural machinery I think we should pursue compressed natural or synthetic gas when there are no liquid fuels left. The gas could be delivered to the farm by truck and stored in 220 bar tanks.

CNG is mostly methane, syngas or producer gas is mostly hydrogen and carbon monoxide. Neither liquifies at reasonable temperatures and pressures.

I ran numbers once, and found that compressing methane to high pressure consumed twice as much energy as was contained in the resulting gas!

I think the best thing to do with producer gas is to make methanol out of it. It can ship and be distributed in existing gasoline infrastructure, and with a bit of work, can be used in gasoline engines.

The compression energy requirements even for hydrogen are not nearly as high as you claim, so I suspect you have made an error somewhere.  Perhaps you assumed isentropic compression when multi-stage with intercooling is the only practical option?

Production of methanol is a very good idea, but unless it is cost-effective at a very small scale it isn't going to beat producer gas made from charcoal or torrefied biomass on the vehicle itself.  Locally-produced methanol isn't going to be available without years of development, so it is not a practical response to a crisis in any event.

Interesting experiment going on at a biodynamic farm in Hampshire, which aims to be 'self-sustaining in energy' by 2010. It is a classic poacher-turned-gamekeeper story in that its owner and prime mover once pissed energy away becoming Formula One world champion. Of course it is one thing to be self sustaining while producing organic livestock for the chattering classes of southern England, quite another to do it while producing flour for supermarket white bread at a competitive price, but fascinating nonetheless. Might he be persuaded to do us a post?


I've never seen a buffalo in the US outside a zoo. Are they actually raised in the UK for milk & cheese? I know that they are in Italy.

I saw dozens just yesterday here in Alberta, and you can buy the cheese in Calgary.

I've seen Bison in Alberta, and elsewhere in North America, but not Bubalus (or Syncerus either, for that matter).

Perhaps you missed the beefalo craze which swept thru the livestock industry some years ago.There are still a few guys out there trying to run bison and bison cattle crosses commercially.

The fences they build necessarily look like five foot high highway gaurd rails!

Incidentally about all you can say for the meat is that it is healthy as meat goes and that if you are hungry enough,it is edible-barely. It might be ok made into meat loaf.

(golf clap)

Fine, you won the nitpicker award. Thanks for reminding me about friendly conversation in the pursuit of knowledge.

When I clicked on the link bugmeister provided, I saw that the UK based website sold buffalo (Bubalus) meat & cheese. I was surprised that buffalo were apparently being raised that far north, so I asked for confirmation from bugmeister that such was indeed the case. I didn't ask about Bison, so you don't need to get all snarky on me. Perhaps you need to review the various bovid genera.

Excerpt from a letter from Marie Celeste to Galileo Galilei,

Lord Father, I must inform you that I am a blockhead, indeed the biggest one in this part of Italy, because seeing how you wrote of sending me seven "Buffalo eggs" I believed them truly to be eggs, and planned to make a huge omelet, convinced that such eggs would be very grand indeed, and in so doing I made a merry time for Suor Luisa, who laughed long and hard at my foolishness.

Apparently a "buffalo egg" is cheese made from buffalo milk that is made into an egg shape?

Yes, Bufalo mozzarella.

From that same book, an image which has remained with me is how Gaileleo's Daughter treasured the two (?) pears which the nunnery tree produced. A sobering reflection of what actually it would mean if food production were returned to that century.

Interesting; Jody Scheckter:

He exploded on the scene as an erratic, crash-prone wild man whose desperate deeds of derring-do put himself and his peers in great danger. Jody Scheckter became infamous for causing one of the biggest accidents in Formula One history, after which there were demands that he should be banned from the sport. Instead, he straightened himself out and concentrated his considerable talent and ambition on becoming World Champion. Having achieved his goal (with Ferrari, whose next champion would be 21 years in the future), he quickly retired.

Hmmm, an organic farmer. Anything is possible in this world.

Now, if Bernie Ecclestone or Max Moseley become an organic farmers, there is hope.

Striving for balance, I say.

This has got to be the biggest load of crapola posted on this site.
I am new to farming 7 years but here's the thing.

A farm is not a closed system. They require a huge support base. Stuff breaks all the time. There is a reason tractors are built so heavy and strong they get hammered and so to do the implements they trail.

I haven't got time to do a long post but without large industries supporting mechanical farm equipment we are going back to animals within a couple of seasons no ifs or buts. Problem is the skill set and animals are no longer there pray for a slow crash...

Marvin,maybe the reason you're starving is that you lack the skills necessary to the mechanical end of your new profession.;)

The newest machine of any consequence on our farm,excepting a chainsaw and my welder,was built in 1992,and thats what we call the "new truck".The "new tractor" is a 1972.The old one would have outlasted us but the manufacturer went broke and we can't find parts or it.

Most of our stuff is fifties vintage and it works just fine-we(personally) could easily go back to full time with this stuff by having some spare capacity .

"we can't find parts"

My point exactly.... Without industrial industry back up our equipment will rapidly become ornamental.

The tractor we can't find parts for is a 67 and was built by a manufacturer in trouble long before that.

We ca still get parts overnight for Fords and Fergusons that were built in the forties.

The farms aren't going down for lack of parts in less than a generation or maybe two generations minimum.

If things collapse faster than that....well there are lots of cows that can be trained to the plow and the cart,and if you own a dozen draft horses you will be a man of stature -unless somebody eats them right in the field while they hold a gun on you.(Ammo will be in short supply too so if they don't need to they won't shoot......)

"...An acre was originally defined as the land area plowable by one ox in a day; the rule of thumb remains one acre per animal per day, so a team of 3-4 horses should be able to manage 3-4 acres per day."

-So if 1 Horse'power' = ~750 Watts all we need is enough energy to power a smallish electric motor that pulls the plough back and forth. I've seen this setup in the first steam powered ploughs -back and forth, back and forth. Farmers must have thought it was a bloody miracle after dragging a heavy plough behind a farting shitting horse for 8 hours...

Now, you can do this all on a nice sunny day and at 20% efficiency will require about 750 / (1000 x .2) = 3.75 metres of solar panel to make it happen. You can slow down or stop for a cuppa when a cloud passes the sun.

But this is missing the point a bit. It's not about whether we can do it with less energy -horses- or what not, but that fossil fuels have so vastly increased our efficiency of food extraction that a tiny fraction of people are now required to generate huge quantities of food while the majority are occupied doing stuff that has enabled civilisation to be where it is today. Think of the energy and complexity involved in something like the real-time global trading of credit default swaps, yes siree, where would we be without these advances!

It is this potential for the forced reduction in societal complexity as the spare/excess energy is diverted back to the basics that is the biggest threat IMO.


A circular saw motor is a couple horsepower, at least. Could a circular saw motor plow an acre in a day? Seems to me the standard definition of a horsepower is a little bit removed from the actual power of a horse, but I could be wrong. Wikipedia cities a Nature article to the effect that a horse can deliver nearly 15 HP peak, but less than 1 HP over long periods. hmmm.

Regardless, even if we have to multiply your number by an order of magnitude (call it 30 panels) there's something to be said for your observation that a small percentage of a farm's land could probably provide power for mechanization, at least at pre-industrial intensities. As usual, the real issue is whether we can maintain the supply chain.

A circular saw motor is a couple horsepower, at least. Could a circular saw motor plow an acre in a day?

Sure, you could rig a winch, you need around 200 lbs tractive force to pull a 12 inch plow. A hp could give you a 200 lbs tractive force at 2.75 ft/sec. You would need a 1 hp surplus after you applied all the gearing or pulleys needed to slow it down that much and that would probably eat up some hp. A 12 inch furrow 43560 feet long is an acre, at 2.75 ft/sec it would take 4.4 hours.

Seems to me the standard definition of a horsepower is a little bit removed from the actual power of a horse, but I could be wrong.

No its still 33000 ft-lbs/minutes. That figure was based on actual working horses observed by James Watt and others. It was inflated slightly so as not to exaggerate the power of his steam engines. When you get into spinning things the applicability isn't alway obvious. Some things spin slowly and produce lots of torque, some things spin fast and produce little torque -- which can make the relationship between torque and horsepower confusing.

So often agricultural equipment discussions focus on plowing - but plowing is really only needed to turn sod or a fallow field into a cultivated field.

Check out this observation from Stonybrook Farm about practical application of the methods described in the classic book Plowman's Folly

A few years ago, when I read Edward Faulkner’s Plowman’s Folly, I was sure that I would never plow a field. However, that idea, like so many of the ideas I developed while cultivating my interest in farming, has fallen by the wayside. As soon as I decided that I wanted to grow some of the grain I feed to the pigs I knew that I would need to use a moldboard plow in order to do so, at least once to break the sod. British dairy farmer Newman Turner in his books Fertility Farming and Fertility Pastures minimized his use of the moldboard plow by only plowing when he needed to break a sod, which was only once every four to six years (I can’t remember how long his rotation was). In every other year, he just disked the field, which he found produced an adequate seed bed. This seems like a good compromise to me.

quoted from http://stonybrookfarm.wordpress.com/2009/06/17/plowmans-folly/

So maybe the relatively rare plowing task is done by a man who maintains and operates a tractor or horse team as a business that provides that service on an as-needed basis. Then the daily on-farm machinery and energy requirements are reduced to a level and scale which is more manageable in terms of on-farm energy production and on-farm maintenance and repair capabilities.

Does this open a better range of possibilities?

A circular saw motor is a couple horsepower, at least. Could a circular saw motor plow an acre in a day?

Look at the size of roto-tillers VS horsepower.

1HP is a small earth mover.....

i think the standard measurement of a horsepower is a bit off; my team of belgians seem to be capable of pulling about half of what my 30hp Ferguson tractor can pull on a sustained basis, which would put each horse at about 7.5 horsepower.

I have never been around any working Belgians for more than a few minutes but we used to have a couple of large mules and they could do amazing things -for a few minutes at a time.

I will bet everything I own that if we put two loaded wagons side by side and hook four Belgians to one and a thirty horsepower tractor in good running order to the other -and the wagons are loaded heavy enough for the tractor to run full throttle at the best horse speed-around two mph I suppose- the horses will be dead tired and worthless for the rest of the day before the tractor burns two gallons of gasoline if they have to keep up with the tractor.

More than likely you would not be mean enough to work them that hard for more than ten minutes or so,when they start lathering up.

So long as the wagon is loaded with a standard working load, I think you would be mistaken. The Ferguson 30 uses approximately 1 gallon per hour, probably a little more with heavy work such as plowing. I don't think a couple draft teams would have much trouble pulling a wagon for a couple hours.

I guess my overall philosophy is that simpler is better if you have any concerns about societal stability. Tractors are anything but simple compared to horses. I formerly lived aboard a sailboat, and anything there of any complexity was always the first to go and the toughest to get parts for. Complexity is directly proportional to failure rates, imho, as well as maintenance costs.

So many people see technological solutions to everything when there are simple solutions (i.e. growing legumes instead of extracting and processing, then transporting nitrate fertilizers). The great efficiency of technological solutions is often not realized when you factor in their down time due to failures of one sort or another.

It's nearly impossible to work a tractor such as your thirty ferguson flat out in first gear due to wheelspin problems,often the same in second gear-which is getting pretty fast,relative to a horse. A horse couldn't maintain the wide open second gear pace very long at all.

So a fair comparision would have to put the loads down to a comparision of work accomplished.

One of our nieghbors used to pull a double turn plow with a Freguson thirty which was equipped with slightly oversized tires filled with calcium chloride for the dead wieght.

You couldn't put the plows in real deep ,or the wheels would spin , but in heavy clay soil he got at two acres per hour ,without rest breaks of any kind, all day.Maybe your horses can stand it sure enough-how many acres per hour can your get ?

Incidentally the small Fergusons of the fifties and sixties are ideal farmstead/doomstead tractors,easy to fix, cheap to buy,versatile-and will last forever if well maintained.

But there are some that are in bad shape due to constant use-not many get that much use,as most tractors sit in the barn a lot-or lack of maintainence. Buyer beware.

where does the fuel come from to power the draft animals ? ... calories

10-15k calories per day ..how many acres for that ?

plus 2000+ calories for each adult per day ... 2.5 acres per adult for calories

so ... 2.5A x 5 (times for animal) = 7.5 acres of land needed for you and your 1 draft animal ...

Organic Farmer .. class of 67, College of Agriculture - CSUF

In general I agree with this post the numbers work great if your in a farming region so I don't see running off to the farm as something that has to happen right away.

However in our modern world the bulk of the oil usage is not on the farm its in the distribution and food prep side of the business. This can happen because people work other jobs and don't have to prepare their own food anymore.

I'm talking about storing the wheat up through bread. Or your variety of imported foods.

Its this second part of the modern food industry that subject to problems.
And of course if people start reverting to full food prep then they don't have time to work and the people that used to prepare the food don't have jobs.

Its not the farm where the problem is.

The cost of food and fossil fuel energy will continue to go up

and eventually food will take up more of the expenditures.

People would be having less time for other things, and they would give up on making some energy-intensive foods (pasta, butter, cheese, desserts). If there were no processed foods, you'd get by on whole grains (you do spend the weekend threshing, I guess...), fruits, stir-fried vegies, beans, meat. Not that hard.

The reason we're in the food mess we're in is advertising. The kids think cereal is normal, and apples, eggs, a slice of bread, are not. My kids are still clamoring for chicken nuggets, two years later!! They think chicken with bones is too hard to get food from. And doesn't taste "right". Now thanks to Ann Cooper they get real chicken at school lunch. I have been too much of a pushover. I am glad someone is helping me!

Jeavons is mentioned above, and in his version of things, people not only avoid "processed" foods, they also eat potatoes, turnips, beets, onions rather than tomatoes, corn, wheat, and rice. That's yet another step from being able to cook what is appealing at this time.

The cost of raw ingredients is abnormally low as a result of people mostly subsisting on processed foods and meat. To correct this, we have to take the food budget, double or triple it, decrease the total number of calories, and account for it in potatoes and rutabagas. That is a problem. Try convincing someone to pay $10 for a rutabaga (organic).

The other problem, as mentioned upthread, is that getting rid of the storage, processing and distribution of food will cut out many, many jobs, and those people won't be buying any food. They'll have to grow it, presumably intensively, focusing on calorie crops. Back to rutabagas.

I have read a piece about small scale nitrogen production using sharp sand mixed with titanium dioxide as a catalyst. it was implied that nitrogen could be fixed from the air then recovered by flooding the sand with water.
Can anyone shed some light on this? It sounds too good to be true, but maybe is not hokum and could be useful on a small scale, just not industrialy - i have no knowledge and seek wisdom here!

Probably late in the thread but I don't know what sharp sand is.
Send me a link I'm a chemist I can help you work through the chemistry. Titanium dioxide absorbs in the UV thats why its used in sunscreen its the buckyball of the inorganic world and probably can do a lot more than we use it for now.

Probably this works from you description but I suspect nitrogen fixing plants are probably better.

A quick google search revealed some papers on nitrogen fixing using a TiO catalyst with various inert substrates.

From a couple of the abstracts it looks like an alkaline solution is needed as part of the process to supply hydroxyl ions, and the ones I saw wanted an initial NOx feed.

So definitely a grain of truth to Frozenthunderbolt's rumor, but the reality appears to be considerably more complex.

I'd go with the plants.

Sand on the beach - not sharp sand.
Sand mined or better yet created from busting up rocks - sharp sand.

The 'sharp sand' will work like adding DE to stored grain to keep bugs 'at bay'.

And example difference - diatamacious earth comes in sharp/non sharp. The non sharp doesn't work for killing bugs. The sharp does.

Being a city boy, I don't know much about farming. But as a small child during the 30's I did spend part of each summer on my grandfather's Missouri farm. My first job was grading corn for the next seasons planting. I was overpaid one dollar by my grandfather. I witnessed the changes from draft animals to machines. The itenerent thrashing machine was operated by a large steam tractor but the wheat was carried to the thresher by multiple wagon teams. Once my grandfather spent twenty minutes or so trying to decide whether to go to town using a buggy or the hand cranked car. I believe he was really trying to decide what would be more fun for me. The 160 acre farm was almost self sufficient with a large garden, an orchard, some wood, pigs, chickens, cows, horses, an ice house, pasture and a variety of crops, generally rotated. Local coal was plentiful. My grandfather also did some work in town and for other farmers. The horses were occasionally used to tow automobiles that got stuck in the muddy roads. Some of our friends and relatives did well and have heirs that are still farming in the area. Some failed. Many left for city jobs. I am told that after WWII the farmers began to specialize, in part due to the cost of the modern equipment. My aunt, Loula Grace Erdman published among other things, a book "Life Was Simpler Then" - a collection of stories about the early days on the Missouri farm.


Impressive bio, 21 books. Thirteen of them showing up on http://www.goodreads.com.

A laudable attempt but the assumptions in this piece of work, combined with incomplete and/or simplified parameters in its mathematical analysis and the system boundary being all wrong for practical purposes made me think it was written by an Economist_Poet not an engineer.

You have to be more explicit than that to carry any cred. here.


You are either entirely lacking in critical reading skills or else you are one of the kind who thinks he knows absolutely everything - and that YOU should be in charge of the subject matter of the site.

Probably both.EP set out to answer a GIVEN QUESTION-not write an encyclopedic work on the history of civilization past present and future as it relates to energy and farming.

There is every reason to suspect that at some time in the not so distant future we could be in a situation such as assumed for the purposes of this article,namely that we still have a functioning industrial ag system but that petroleum derived diesel and gasoline are in extremely short supply.

Presumably you have not heard of wars, or embargos, or shark fin depletion curves yet.

Or maybe you are an arm chair superliberal and you plan on just legislating fuel into existence in the event of a sudden shortage.

Was your intellectual grandmother by any chance known as Ma Kip?Or maybe you are just a lawyer short of work and irritated that you weren't paid to add a dozen pages of whereas and therefore to the article.

EP has done a fine volunteer job.

"functioning industrial ag system but that petroleum derived diesel and gasoline are in extremely short supply."

A contradiction in terms. Enough said.

"Presumably you have not heard of wars, or embargos, or shark fin depletion curves yet."

Actually, I have. I read the Oil Drum. The notion that an unexpected war or embargo of FF supplies will be significantly mitigated by alternative fuel use in tractors is a stretch. Think about the transition process rather than just focusing on the technological possibilities.

"Or maybe you are an arm chair superliberal and you plan on just legislating fuel into existence in the event of a sudden shortage."

How silly. Your true colors are showing through. Do you watch Glenn Beck?

"maybe you are just a lawyer short of work and irritated that you weren't paid to add a dozen pages of whereas and therefore to the article."

Again, plain silly. I'm a Mechanical Engineer (graduated in the UK with Honors in 1986) who now farms small-scale using permaculture and biointensive methods.

"EP has done a fine volunteer job."

The typically weak endorsement for the work of amateurs. The fact is, whilst a simplistic energy balance and niche technologies may give you and lengould the warm and fuzzies about the impact of FF interruption on the food supply, people who don't live on/near farms will will be severely challenged unfortunately. Tax and industrial policies aimed at reducing meat and processed foods in our diet and encouraging local, small scale Ag is where we should be headed to increase the robustness of our end consumers' food supply (to FF interruption/depletion and/or bioterrorists and accidental contaminations for that matter).

The Economist-Poet reference was based on the lack of an ecological foundation in the original article. I live and work with sugar cane plantation workers. A cane plantation exhibits some of the characteristics EP was aiming at I believe (industrial scale, mechanized, crop byproduct (bagasse) used as fuel. The plantation land is notoriously denuded and the soil erosion rate is one of the highest anywhere. The proposition is a dead end medium-to-long term and impossible in the short term from a transition/logistics perspective.

Just because something is a volunteer effort doesn't make it correct. It does make the effort laudable as I said originally and useful as a basis for group development. You and lengould however inhibited that process and sound like EPs irate dad at his/her after school soccer game.

We could spend a few days argueing the meaning of "functioning "-there was/may still be a three billion dollar lawsuit in progress in regards to the time interval between the planes hitting the towers 9/11.Less than half an hour.Two events or one?Double the money if two events-read up on it in Pinker's the Stuff of Thought.

Any petroluem shortage that develops will almost certainly not be total ,unless there is either a flat out nuclear war,or maybe a plague of biblical proportions-all bets would then be off anyway.

We could PROBABLY MANAGE to keep that "contradiction in terms" running for a while by dint of draconian rationing-long enough in my estimation to get rolling on a large enough change in on farm operations that farmers can carry thier own wieght fuel wise for an indefinite period.Of course not every farmer would necessarily grow his own fuel ,or process it on his own place.

But farmers on the average could increase thier production of oilseeds ,etc, pretty fast.
This would of course lighten the load considerably for all other essential people in terms of thier getting enough fuel to carry on thier work ,such as police ,fire, grid maintainence,etc.

So that "contradiction in terms" just might continue to function and people might just continue to eat.This is not such a minor consideration in most folks opinion unless I an mistaken.

"Think about the transition"

The whole article IS about a transition-one that just might possibly save our butts until we can do something else better suited to the long run-something outside the scope of the article..You might be expected might notice such a not so subtle fact, being a well educated man.

Now my remark about your being an armchair liberal was uncalled for and I apologize but my comment about your critical reading skills stands.If you as an engineer attempt to write a short report outlining the possibilities of a given technology working perhaps for a short time ,perhaps on an emergency basis,you would not appreciate some holier than thou bueracrat condemning your piece because it didn't go into dozens of possible variations of the problem under discussion, or condemn all existing infrastructure as unworkable and redesign the world in one fell swoop.

(Hence my remarks about unemployed lawyers.)

Now that WOULD be an accomplishment ,would it not?Especially if it would fit into the space alloted for a single piece by this website(which incidentally is not a peer reviewed journal but a forum for the exploration of ideas,possibilities,and facts) ,and you pulled it off all by your lonesome.I expect Princeton and Harvard would name a new building after you and follow you around begging you to join them.Of course being a good Englishman I couldn't blame you if you stuck by

i have a degree in ag myself and am quite aware that industrial ag as we know it is a dinosaur and headed for the dustbin of history,and have said so many times on this site.

I also have been farming,or helping on the family farm -and mostly earning a living at it in defiance of the odds for many years.

Furthermore I try to read at least one serious book a week-meaning one written by a profesional in good standing in his field-history books ,biology books, psychology books, economics books,including quite a few books oriented towards engineering problems and issues.

I have been maintaining this pace for almost fifty years.So I am perhaps not such an amatuer as you might suppose in understanding the workings of this old world.

Now I will modestly submit to you that we are absolutely compelled to keep that '"contradiction in terms" functioning for several more decades at least before there is any real hope of changing the way we obtain our daily bread-else we starve by the tens of millions,by the hundreds of millions probably.

We cannot change our food supply system any faster unless some sort of Black Swan event -something along the lines of Pearl Harbor changes the political and economic equation.Surely you recognize the truth of this statement ,being an engineer.

We can't even change the way we get our energy any faster,and that involves far fewer disruptions of day to day life-somebody living in a big city generally doesn't know or care if his electricity is nuclear, coal , or wind derived.So long as the lights work.....

I can assure you he will feel differently about his food-especially if he has to change his lifestyle in order to obtain it-maybe by working in a community garden,or by paying twice as much for it.

As a society we we must evolve incrementally,in the same way as an organism evolves by evolution, for the most part.We can't just do this change over as if we were installing a new computer system over the weekend.

EP has shown us a patch that can keep the old system running,temporarily, if one part of it fails.

Apparently you just don't want to recognize that.

His solution -really his answer to a hypothetical question-is certainly as sound as the solutions to many problems worked out by the engineering profession and in place all over the world.Not too many of them have continued to collect a paycheck by saying this highway is no good because there will be no oil in the future or this dam is no good because it disrupts the river ecology.Nobody has permanent answer to any problem so far as I can see, except the one that goes " in the long run we are all dead".

You throw up a straw man by talking about the way suger cane is grown ,which is probably the worst of existing systems, and implying that since this worst case exists, all on farm fuel production will be as bad.Sorry but I was once in a debating club ,and took a course in logic somewhere along the way too.

Such techniques work if the listener is uninformed.I trust that the typical visitor here is well informed.

I look forward to your piece that solves all the problems without creating twice as many new ones.

Danke schön.

You are most sincerely welcome.If Mauiorganic(now there is an interesting handle-personally back in the good ole days I enjoyed some very fine smoke but never any maui wowie!)had even bothered to read the comments he would have seen your much earlier comment that on farm fuel production gets us a reprieve only, not an amnesty.The whole point of his comment was imo just to preen his holier than thou feathers.

If you want to bust his chops over being the 'Economist_Poet' you can dig 'round the net back when he was pimp'n 'lets strip the forests and make zinc batteries' series where he claimed returning the byproducts back to the land was not needed and if the soil needed the material back, economics would make that happen.

He's made great growth in understanding, tho his ego won't let him admit he was wrong.

If you want to bust his chops over being the 'Economist_Poet' you can dig 'round the net back when he was pimp'n 'lets strip the forests and make zinc batteries' series where he claimed returning the byproducts back to the land was not needed and if the soil needed the material back, economics would make that happen.

He's made great growth in understanding, tho his ego won't let him admit he was wrong.

The downside of biogas is that it is a gas, and storage cylinders are heavy and bulky. Materials likely to be on-hand would leave a a great deal to be desired: low-pressure cylinders such as propane tanks can contain biogas but would hold relatively little fuel even if it is purified to remove CO2. A 250-gallon propane "pig" pressurized to 250 PSI would hold the equivalent of about 4 gallons of diesel fuel. It might be possible to get work done this way, but refueling would be very frequent and take a great deal of time away from work.

ANG storage offers somewhat of an improvement. DOE's goal of 118 g/l was met at about 40 bar. Gasoline density is about 730 g/l. Also grasses are feasible feestock for biogas as well as manures. Yields on the low end are about 300 litres of methane per kg ODM, thats about a 65% conversion. Maize yields in the 350-400 litre/kg range.

A biogas plant in Linkoping, Sweden produces 807,000 cu ft a day, and capital costs were $2,133,333 US. Transportation distance for feedstock is limited because its heavy and wet, but the capital costs are low enough to make it feasible on a smaller scales that farm coops would be doing.

If you can get proportional capacity at lower pressures (say, 16-18 bar) and the media can be made by laymen using common materials, you'd have something.  Biochar or carbonized chicken feathers may be easy enough to obtain to make conversion of available tankage such as propane cylinders feasible.

BOTE:  heat of combustion of methane is 191 kcal/gm-mol.  A tank storing 47 g/l at 16 bar would store 561 kcal/l or about 8400 BTU/gallon.  250 gallons of volume would hold the equivalent of about 15 gallons of diesel—not a bad improvement, especially if the weight was needed for traction.

Here are some 275 psi cylinders on the market,


The largest one has inner diameter of 12", height with cap at 48". Its not a cylinder all the way up to 48", I'll guestimate a strict cylinder 42" tall has the same volume. Volume 4750 cubic inches, around 20 1/2 gallons. It holds 130 cu ft of methane, approximately the energy of a gallon of gas. Looks like at 275 psi this implementation would extrapolate to around 12 gallons equivalent in a 250 gallon volume.

It never quite matches the storage of 3600 psi CNG, its about 2/3 of the way there at 500 psi. It maxes out at around 1450 psi, returns diminish long before that.

Good stuff.

Some have suggested that shortages of petroleum could produce a collapse of mechanized farming in the near term, with all that implies. This scenario does not appear to be realistic.

I'd agree with that. IEA figures suggest that 3.5% of EU primary energy consumption is used in agriculture, and I'm pretty sure a way will be found to priorities use of dwindling petroleum, when the time comes. And as you point out, farms are ideally positioned to run on farm waste.

However, I've also read recently that 20% of primary energy use goes into the food industry supply chain - processing, distribution etc. That seems an awful lot to me, but, if true could spell major problems in getting food off the farm and on to your plate.

Distribution isn't an option, but processing may be.  Replacing processed fruit products with raw or dried fruit would probably be an improvement; replacing sugary cereals with oatmeal or cream of wheat certainly would be.

I have commented many times in the past that I can not verify EROEI on my farm, but I will not go into that again here.

I do want to point out that there have been significant recent changes in corn and soybean farming since about year 2000. Cultivation and "plowing" are no longer the big energy consumers they once were.

This is because of recent advances in biotechnology and glyphosate (Roundup). Corn and soybeans are now bio engineered such that much of the traditional cultivation no longer is required. It is not really a question of draft animals and mechanical equipment any more.

What is really going on is a big increase in genetically modified crops, glyphosate and much less cultivation.

Less cultivation means not only less energy use for fuel but a much reduced need for farm equipment. Conventional moldboard plows, the staple of cultivation for over a 100 years, are now obsolete and go for next to nothing at farm sales. The same goes for row crop cultivators, rotary hoes and such since crops are now sprayed once with Roundup and that is it. The sprayer doesn't use much fuel since in turns no soil.

No till farmers don't even plow at all. Their planters do all the work. The other piece of equipment that is needed besides a sprayer is a combine for harvesting. I don't do no till, but my equipment is very old. Some of it is 50 years old. My tractor I bought new in 1983. I buy old combines and repair them to make one good combine. So that is my angle on energy. With much reduced tillage, new equipment is less necessary.

The constant replacement of farm equipment is not required. It is mostly a tax write-off by wealthy farmers with nothing better to do with their money. The Section 179 depreciation has been increased from $20,000 to over $200,000 in recent years as Bush's tax cuts for the wealthy took effect. That is very tempting for big farmers and even for me. Why give the money to the government when you can ride around in a new JD combine or tractor and look smart whether you really need it or not.

The article is correct that the energy produced on farms far exceeds the the energy consumed despite all the falacious EROEI/Net Energy nonsense often posted on TOD.

Exactly. Though how does one get to be one of those "wealthy" farmers? None of them herein Canada, even in the corn belt of southern ontario. Inherit land in a subsidy-rich country I suppose?

That's about the size of it ,Len-inherit it ,marry it, or get rich filling teeth or trading stocks and buy it for the reasons mentioned.

There is a huge surplus of farm equipment around for the reasons x mentions.

Being from Missouri, economic and energetic analysis wasn't enough. There was a need to prove it to myself. Somebody had to "show-me". So, a former energy engineer became a draft horse farmer apprentice for a while. Making that switch was one of the scariest, hardest, and most fulfilling things I have done. My life has been forever changed.

This post caught my eye but didn't raise any eyebrows or make any points that I would argue against. But there was something beyond the balanced equations, embodied energy accounting, and life cycle cost analyzes, out there in the soil and in my former four-legged working partners. Dare I call it a spiritual factor that one will be hard pressed to experience without getting one's hands dirty.

Just in case you're curious:

From a practical experience, I believe that EP's figures are too positive but I globally agree with the conclusion.

I run a small farm of 35 hectares as a hobby. I have 1ha of vineyard, 6ha of grass and 28ha of crops. It might not be the most efficient farm, but it is an average farm. I need about 2,000 liters of diesel every year to run the farm. If I were to use rapeseed oil to run my tractors, I would have to dedicate 2ha of rapeseed every years for this purpose. this is about 6% of the farmland.

The need of nitrogen as fertilizer is not included in this equation and would increase the toll. I cannot quantify what percentage of the land would be needed though. I have not yet found a way to be independant from fertilisers made from fossil fuels.

80 years ago, the same farm of 35 hectares required at least 4 horses and employed 6 people full time. Now it only requires some of my time and an employee full time. In case of crises, I can run the farm alone.

So I naturally come to the same conclusion as EP that I will keep my tractors instead of going back to horses times, especially that this requires less of a change in my knowledge of technology than to re-invent how my grandfather used to farm his land.

One factor that cosumes enormous amounts of energy/maintenance costs is corrosion. You need to factor in maintenance costs as well as cost of manufacturing replacement parts.

Also include transportation cost from factory.

Tires vs. horseshoes. Not just calories, but how available are tools, raw materials, & skilled labor required to produce final product.

When I had draft horses I used horseshoes (St Croix) I believe made in Minnesota imported to Australia. They were double the size of standard horseshoes but required little shaping for that breed. However when a 900kg clumper decides to lean on you it's hard on the back. All very nostalgic but those days are gone.

I feel that in principle you are correct.

However simple modification of current technology probably won't be enough.

I expect a farm of say 2075 to be mechanised ... but the machines may not bear any relation to current clunky tractors and combines.

I doubt that any of today's machinery will be more than museum pieces in 2075.  However, how the machinery of 2075 will be different depends on whether or not we have the crash that some people are predicting, and if so, how capably we deal with it.  I can see fumbles leading to the late 21st century machinery looking a lot like the early 20th century machinery, made from the abundant scrap.  A BAU scenario would probably lead to machinery using methanol fuel cells or even all electric.  After all, if batteries are good enough and you need to carry the weight for ballast anyway....

I have friends and relatives in Eastern Kansas. Much of the land is ideal for grazing. I am told that some is unsuitable for cultivation. One can drive north and south and see many cows and few people. . Any opinions as to the future of this beef industry.

Unless the climate changes it is probable that the land you mention will be used to raise cattle indefinitely as there is a good net yield of high quality and very highly palatable protein.

There is more than enough land better suited to cultivation of staple crops and fruits and vegetables for the forseeable future-several decades at least.But only a fool would predict what the population might be ,or what programs might be put in place much farther out than that.

Somebody might be in a position to outlaw the consumption of meat for instance-stranger things have happened.

This “study” will not stand up to a closer scrutiny. It is nothing more than a compilation of superficial observations without any serious discussion of the interrelatedness and possibility that not-farm factors might upset the arguments. It simply lack the thoroughness such a serious issue deserves. The contra arguments are scattered through the as of now, 248 comments.

Just consider what the EROI of sunflower oil has to be to make any sense if Engineer-Poet is right in his/her assumptions.

If the main crop does not yield oil, some small amount of land can be devoted to oilseeds. Sunflowers or canola will do for this. At a yield of 77 gallons per acre, one acre of canola would supply ignition fuel to till and harvest 150 acres. Such a modest amount of oil would be easy to produce locally.

It is simply irrelevant to produce this oil for the uses discussed, if the EROI isn’t hugely positive.


Obviously you have not read closely,and have not thought your argument thru.

The acre of canola can iteslf be cultivated and harvested by cannibalizing a little of the production.Futhermore no where..it's no use to go thru this again,I'm wasting my time.

Why don't you read the article and the comments thru CAREFULLY?

I am sadly disappointed at the general level of critical reading skills demonstrated recently.

There is no xxxxing hope for us if the readers of this forum are as dense as the comments this time around suggest.


Who are you to call me dense!

The vegetable oil is just one tiny little aspect of the logic flaws of this article.

Perhaps you should familiarize yourself with Systems theory……

And if YOU have read the comments closely, you might have grasped that there are other concerns too. But I guess you are too busy creating off topic comments. The search function of my web browser tells me you have produced 26 comments so far on this story. Many, if not most of those, does nothing to illuminate this topic. Such empty comments do make the comment section of The Oil Drum to a jungle where one has to use a machete to get through. So that’s what I have to do since I have a life to attend to. But in doing so I DID get that there are many critical comments and concern in between your comments!


I went over examples of everything I mentioned, including the use of small amounts of liquid fuel providing pilot ignition for a main gas/air charge in a diesel engine.  The devotion of < 1% of the land area to provide such a small amount of fuel as SVO from a dedicated oil crop, or < 2% of a corn crop pressed for oil (which might be less than is normally pressed anyway), is quite practical; just reducing the fraction of meat in the American diet by a small proportion would provide it, and in a fuel emergency such would be among the smallest of issues, the effects unnoticed among the other changes.

Yes, you are right that there are other concerns.  These concerns are present even without a fuel emergency, to a greater or lesser extent.  On the other hand, the fact that the energy content of corn stover is several times as large as the combined energy requirements of cultivation and Haber nitrogen fixation is hugely important.  It points out possibilities that are not often mentioned in these circles, and the potential for building mechanized systems with no fossil inputs while in operation (and even surpluses for other uses).  If you don't think about the impact of such changes on broader systems, you're not going to be taken seriously when you try to lecture the rest of us.

Perhaps if you would read CAREFULLY you would see that most of these comments acknowledge and expand upon the problems.

Perhaps you might notice that EP says that this whole deal needs to be tested and researched NOW,thereby acknowledging possible pitfalls and correctable( or not) shortcomings..

Perhaps you would notice that he said in reply to my FIRST COMMENT that on farm fuels will earn us ONLY A REPRIEVE, NOT AN AMNESTY.

I think maybe you lack reading skills.

As it happens ,I am rather familiar with the portion of systems that relates to farms.

You fail to note (you have not READ, YOU ONLY SKIM) that nearly everybody who actually farms commercially agrees .Of course there are some with enough money to do uneconomic things.

My own actual farm work is going unattended because I spend most of my time attending an invalid,which is not steady work but it keeps me in the house.It leaves me plenty of time between dispensing drugs,spoon feeding ,etc, to get into the mud like a pig.

I'm kinda like the building inspector -I ENJOY these little disputes,especially when I'm holding all the aces and wild cards.

If you have READ MY comments you would realize that the FIRST ONE is a warning against the pitfalls of bio fuels in general and farmed biofuels in particular.I won't go so far as to quote myself ,since it's there for all to see on this very page.

Theoritical discussions about reorganizing the world are fine. Tomorrow and next yeat and the year after that ARE NOT a theoritical consideration.

You are DENSE because you do not realize that this piece is about possible incremental change in that direction.Either that or you just comment without reading carefully.There are many kinds of true believers in this old world.

Apparently you are one of the sort that knows the price of every thing but the value of nothing -such as a contingency plan that mught just keep you and yours alive.

Put your type in charge and we would be starving in two years.

Personally I make a serious effort to balance my wishes and desires with a dose of right here, right now reality.

That means I read Marx and Lenin , read the NYT, listen to the BBC,as well as some right wing writers.I TRY to see both sides.

I suppose that comes of having taken many course in the liberal arts, but not quite enough for a degree.I did finish my science based degree in ag-I KNOW what I am talking about.

Now if every one wants to start over at the beginning and talk about the future of agriculture some years or decades down the road, I'm agreeable, and not only that-my comments in regards to the eventual necessity of organic farming ,localization ,moving down the food chain, etc are already up over the last few months.

This article is about EP's insights into the possibilities.His insights are good.

I'm reasonably sure the tptb here on this site would welcome your rebuttal ,although I cannot speak for them and do not presume to do so- but they DO run contrary pov pieces quite often.

It is simply irrelevant to produce this oil for the uses discussed, if the EROI isn’t hugely positive.

It only needs to be significantly better the feeding draft animals.

I find it much more likely that we will get more dairy cows then draft animals, at least in Sweden. Cheese, butter and dried milk are nice export goods and cheese, butter and milk are age old staples in our diet, we have even evolved to drink milk. It would make it possibe to as in old times get food from marginal lands but that would of course need lots more manual labour for fencing in areas and tending he cows. If small scale dairy farms would start to make sense I expect them to displace the numerous small hobby stables and that the horses end up eaten with horseradish.

More cows can offset the lower productivity of a cow diet withouth imported soya and they can eat locally produced grass, oats, nitrogen fiating alfalfa and clover and press cake from the rapeseed oil production. The manure can then be used for biogas production and complemented with boiled or acid treated straw. This would only be a gradual change of how our farms are run right now.

Farms close to towns will probably pipe the biogas to them during most of the year but draw biogas from the network during planting and harvesting. If it does not even out it can be complemented with gasified wood or imported LNG, our first small LNG terminal is being built right now.

I expect that manny farmers will invest in a battery powered utilty tractor or beam loader for all the small work.

On Memorial Day in Bishop, California the annual Mule Days parade offers up many harnessed wagons, but this is relatively high technology, no? Relatively. Once in infamous Willits, California I saw a team of beautiful Shires pulling a preserved logging device down Main Street in the Independence Day parade, maybe two years ago. Its wheels were huge, maybe as much as 10 feet in diameter. (Check Roots of Motive Power.) In the old days the team would drag a large log out of the woods, the end on the ground providing braking power.

The log in the parade was long but not huge. But in my limited experience of small town parades one sees many riders but few wagons, because harnessing and all that is quite a feat.

So I conclude that farm machinery with or without draft animals will survive in a fast crash scenario only in scattered pockets on good agricultural land and only for a short while. Something to fight over. Why assume this "transition" will be orderly, gradual or convenient for the provision of 6.7B humanoids?

Given overshoot, a fast crash scenario is the one that makes sense to me. Just saying.

Nonetheless, the skills are being preserved, and those who know will find no shortage of eager apprentices should worse come to worst.

It might get pretty bad, disorderly, and inconvenient, but I think that people will come through as usual in hard times.

I would have thought that it was clear that this article was just addressing the short-term, in which farmers had to cope with a fuel shortage with their current equipment. The article provides a nice theoretical boundary to the discussion by showing that farmers can produce their own fuel, if necessary.

On a more practical level: most farmers are small and suffering, but most farm acreage is being managed by large organizations, and is reasonably profitable. Those organizations will just raise their food prices, and out-bid personal transportation (commuters and leisure travel) for fuel, so they'll do just fine. As farm commodities are only a small %of the final price of food, it won't make much difference to food prices. The distribution system, too, will outbid personal transportation for fuel. Given that overall liquid fuel supplies are likely to only decline 20% in the next 20 years, that gives plenty of time for a transition.

In the long term, I would think that electric tractors and combines would be the obvious solution.

Farm tractors can be electric, or hybrid . Here's a light electric tractor . Batteries can be trucked to the field in swappable packs. Farm tractors are a heavy fleet application, so they're not subject to the same limitations as cars and other light road vehicles (i.e., the need for small, light batteries and a charging network). Providing swap-in batteries is much easier and more practical. Zinc-air fuel cells can just be refuelled. Many sources of power are within the weight parameters to power modern farm tractors, including lithium-ion, Zebra batteries, ZAFC's and the latest lead-acid from Firefly Energy, and others.

Nick, FWIW, Colin Campbell predicted (in the December 2008 ASPO report) a 31% decline in all liquids for 2010 to 2030 (from 80 Mbpd to 55 Mbpd).


Kjell Aleklett, President of ASPO International: "Rather than oil production rising by 20 per cent to 101.5 million barrels a day in 2030, he says production is likely to fall 11 per cent, to just 76 million barrels a day."


Look at page 40 of the presentation: http://www.aspo-australia.org.au/References/Aleklett/20090611%20Sydney4.pdf

I was just reading a fairly generic web news document about how much of the poverty in sub-Sahara Africa is due to the extreme exhaustion of their soils, no organic matter in the soil, so bad that even subsidizing the application of chemical fertilisers doesn't help much.

So I'm thinking, let's say for example there are 100 million small subsistence farmers in Africa trying to live from what they can raise on 1 acre of land.

So how about a program to actually plant and then till in four consecutive green-manure crops on farmland which is severely degraded. A development agency approaches these farmers with offers to (a) pay a $2,500/year stand-down fee for subsistence while they grow 4 crops in 2 years of a high-production legume, (b) provide them the seeds and fertilizers based on soil analyses, (c) purchases and provides them livestock feed for the 2 years if necessary eg. 4 tons hay x 2 years x 50% of clients , and (d) arranges its own tractors to come round 4 times to rotary till the crops into the topsoil training local tractor operators for the job eg. each $50,000 100 hp tractor doing 2,000 acres of land 4 passes in 2 years using 1 gallon diesel per acre per pass and 1 gal per acre traveling, manouvering small plots etc. Tillers re-seed and fertilise next crop on same pass. Operators are 10% of those being paid to stand down with a $1,250 / yr bonus.

Local tractor factories of course. Arrange that the replacement payments should largely go to other local farmers. The business stimulation alone of the added financial activity would be a macro benefit.

For at least some relief of poverty among 100 million farmers, the total $665 billion would be worth it. Definitely needs research first into proper crop selection, growth cycles etc. per area......

The point is not to replace diesel tractors by other tractors, but to diminish energy use in general.

In the case of arable farming deep ploughing and mineral fertilizers are consuming most energy.

Indications from the Iowa Farm Bureau on limiting carbon emissions (thus energy use) by "carbon farming"
No-till farming reduce carbon emissions with:
- no till: 0.8 tons per hectare per year
- less fertiliser needed: 0.8 tons per hectare per year
- less irrigation needed : 0,4 tons per hectare per year
- increased humus content, due to leaving crop residues on the land 0.1 - 0.2 tons

With agroforestry and Ramial Chipped Wood added to the system the humus content growth will be doubled due to the lignin based organic material, with tenfold more stable humus growth

Adding crop residues, trees, or RCW is a very energy efficient way of improving soil fertility!

See my blog:

Could you provide a link to an introduction to Ramial Chipped Wood, for those of us who have never heard of it before?

I am particularly interested whether wood is required or tall grasses might achieve the same result; the productivity of switchgrass and Miscanthus giganteus is much greater than most wood crops.

Best introductions to RCW:

Ramial Chipped Wood: the Clue to a Sustainable Fertile Soil (2007)
By Diane Germain, Ph.D., P. Eng.

Scientific article of the “inventor” Prof. Lemieux of RCW, Laval University

The productivity of switch grass might be higher if you compare one ha of wood with one ha of switch grass but there are two essential issues why RCW still wins:

- RCW from broad leaf trees contains more lignine, which is the basis for stable humus (it makes circular molecules that are difficult to decompose), it decomposes into 30% of the original C content, to 2 to 5 % of non-woody material.

- RCW comes from trees that can be grown in an agroforestry system (at the field margins, or field rows, with less than 50 trees per ha). In this way the competition with the crop is limited (the tree roots can grow in different soil layers, and light competition is minimal, when regular pruned). In case of switch grass one or several production years need to be sacrificed.

Lignine rich material is also essential to get back beneficial fungi into the trophic chain of the soil.

The energy costs of shredding the branches are included in the equation above (about 1 liter of gasoline for one m3 of RCW, you need 10-50m3 per year per ha, depending on the soil/climate, to replace fertilisers). In the first years though, while building up the humus content, extra fertilizer is necessary.



The point is not to replace diesel tractors by other tractors, but to diminish energy use in general.... limiting carbon emissions (thus energy use)

You're not concerned about energy, you're concerned about CO2 emissions. Electrical generation, from wind and solar, produces very little CO2.

Even when you replace diesel tractors by electric ones, in a post peak scenario, energy will be much more expensive than now. No-till farming requires much less energy (deep ploughing requires most energy in arable farming) so it is seems more logical than using electric tractors for deep ploughing. It is simply not necessary and even better for the soil. If you add RCW, you can also economise on energy for fertilisation and chemical pesticides....

It is simply not necessary and even better for the soil.

That's great.

in a post peak scenario, energy will be much more expensive than now

There, I have to disagree. Electricity will never be very expensive (say, substantially more than $.25/KWH) in the US: the wholesale cost of wind power is below $.10 and that will continue to fall.

I did a study on this once, and came to the conclusion that SVO could have an ERoEI of 15:1 -- in other words, one acre of rapeseed could produce the fuel needed for mechanized farming on an additional 15 acres. I think the 150:1 calculation in this article is optimistic.

Still, 15:1 is pretty good. I used USDA figures for fuel per acre. But if you use no-till and low-till techniques, it looks quite reasonable for the small farmer to have an oilseed crop somewhere to power the rest of his operation.

150:1 is based on 90% of the energy coming from fumigated bio-gas or producer gas, which can both be made from crop straw or stover rather than pressed from seeds.  I'm assuming that only 10% ignition fuel is required.

Note that removal of the diesel injection system and replacement by spark plugs would allow 100% of the fuel to come from gas of some sort, but it would not be as quick a changeover nor as flexible in fuel requirements.