The Man Who Wrote the Book on Algal Biodiesel

The following is a guest post by John Benemann. John has many years of expertise in biomass conversion, and previously co-wrote a guest piece on cellulosic ethanol. On the subject of biodiesel from algae, he literally wrote the book.

I originally wrote an article over a year ago in which I mentioned the potential of algal biodiesel. I still believe, as I did then, that biodiesel (or more broadly, renewable diesel) is a far superior fuel to ethanol for reasons I outlined in that essay. However, over the past year, the more I learned about the prospects of biodiesel from algae, the more it started to look to me like cellulosic ethanol: Technically feasible? Yes. Commercially feasible? Nowhere close, and the prospects don't look good any time soon. (However, as in the case of cellulosic ethanol, I believe the technology has some potential, so the government should fund the research).

This was a bit disheartening for me, because I had high hopes that we had an option for replacing a large amount of our fossil fuel usage. I no longer believe that, and recent work by Krassen Dimitrov (PDF warning) had reinforced my doubts. When I read the guest post by fireangel, "Has the Algae Cavalry Arrived", my first thought was "Nice work." My second thought was, "I should have jumped on this and investigated thoroughly eight months ago when those nagging doubts started to creep in." One nagging question I have had since I first read about biodiesel from algae is "Why would NREL terminate the project if the prospects really were good?"

But should there be any further doubts, here is a guest post from a man who knows as much about this subject as anyone else in the world. And he bears bad news for those who had visions of driving around in algae-fueled transportation.


I saw with some interest the guest post on "Has the Algae Cavalry Arrived" posted by Heading Out and written by fireangel about the claims being made by GreenFuel Technologies (GFT) Corporation. I have some standing in this matter, both as Manager of the International Network on Biofixation of Carbon Dioxide and Greenhouse Gas Abatement with Microalgae (operated by the Int. Energy Agency, Greenhouse Gas R&D Programme) and also as a researcher in this field for over 30 years. My comments here are my own, of course, and don't necessarily reflect those of the GhG R&D Programme or others involved in the Biofixation Network. In brief:

1. The post by fireangel, based on the analysis by Dr. Krassen Dimitrov's, is generally correct, although some details regarding algae physiology and mass culture are arguable. However, those would not change the general conclusions of this posting. Well done!

2. The claims for biodiesel production rates being made by GFT, among many others in this field, exceed anything based on biological or physical theory, as also pointed out in this posting. They are truly bizarre.

3. The use of closed photobioreactors (>$100+/m2) for such applications is totally absurd.

4. I am on the record as stating that this is "It's bizarre; it's totally absurd." (see below article from the American Scientist last year, which quotes me to that effect. This was a correct quote, and in context).

5. Open ponds, at <$10/m2 can be as productive as closed photobioreactors. The arguments that closed systems are better than open ponds are incorrect - they both have their particular applications and benefits/drawbacks. It all depends on the situation and applications. The main difference is that open ponds are much cheaper.

6. Open ponds may plausibly be considered for algae biofuels production, but this assumes that indeed the required R&D is successful, a very BIG IF (but that is true of all R&D). But it is worthwhile trying, as we must try all plausible options. But we must also reject those that, as pointed out in this posting, violate first principles and have other major up-front failings.

7. I was the Principal Investigator and main author of the U.S. DOE Aquatic Species Program (ASP) Close-Out Report [RR: You can download this 328 page PDF, which I have actually read, here], and thus am rather familiar with it. The report was published by NREL with their own introduction that paints a perhaps somewhat too-positive picture in light of the actual data and results. Thus it should be used with some caution. This report was meant to just summarize the work done by the ASP, which spent about $100 million, (in today's dollars) over about a decade and a half.

8. Microalgae biofuels generally, and algae biodiesel production specifically, is still a long-term R&D goal (likely about 10 years), that will require at least as much funding as the ASP, if not more, and success is, as for any R&D effort, rather uncertain.

9. Some near term applications can be considered, in wastewater treatment specifically (but, wait, do not rush to your nearest algae wastewater treatment ponds - there are thousands of these around, but they are mostly very small and their algae have little or no oil, at least the way that we operate those systems at present. Making oil from algae grown on wastewaters also still requires significant R&D).

10. There are now scores of venture-financed companies, university research groups, government labs, garage start-ups, GFT licensees, web sites, and on and on claiming that they have, can, may and/or will produce algae biodiesel, at low cost, high productivity, soon, etc. None are based on data, experience, reality or even a correct reading of the literature.

11. I am not aware of any work in this field done by Prof. Briggs at U. New Hampshire, outside from an old website that quotes the Aquatic Species Program Close Out Report. There is no basis for the projections he makes for very high biodiesel production rates.

12. Even if R&D proves successful and we can actually produce algae biofuels (maybe even biodiesel) economically (whatever the economics may be a decade or so from now), even then, I am sorry to say that due to resource (land, water, etc.) limitations, algae will not replace all our (or their) oil wells, cannot solve our entire global warming problem, or make me rich quick, at least not honestly. But maybe this technology could be developed in the next few years so that in the future it can make a contribution to our energy supplies, our environment and human welfare.

We will in the future need all such technologies and must in the present study and develop all those that appear at least on their face plausible. But we also must reject those, as in the present case, that are based on absurd claims (such as in this case of productivity) and bizarre contraptions (e.g. closed photobioreactors).

There are no silver bullets, no winner-take-all technologies, no technological fixes, the solution to our energy and environment crisis can only come from, in order, 'demand' management, efficiency improvements, and new energy supplies, to which, maybe, algae processes can contribute.

I hope that this posting helps persuade GFT, and all others in this "business", to CEASE AND DESIST from the absurd and totally bizarre claims they are making. PLEASE!!


John R. Benemann, Ph.D.

American Scientist Article Excerpt

The full article is:

Grow Your Own?

The excerpt to which Dr. Benemann referred:

The people now working on these and several similar commercial ventures are clearly eager to make growing algae a going business in this country. Yet it's not hard to find experts who view such prospects as dim indeed. John R. Benemann, a private consultant in Walnut Creek, California, manages the International Network on Biofixation of CO2 and Greenhouse Gas Abatement with Microalgae for the International Energy Agency. He helped author the final report of the Aquatic Species Program and has decades of experience in this field. "Growing algae is cheap," he says, but "certainly not as cheap as growing palm oil." And he is particularly skeptical about attempts to make algal production more economical by using enclosed bioreactors (rather than open ponds, as were used for the Aquatic Species Program). He points out that Japan spent hundreds of millions of dollars on such research, which never went anywhere. Asked to comment about why there is so much effort in that direction now, he responds, "It's bizarre; it's totally absurd."

Canola/Flax intercropped on summerfallow cultivated with electric farm equipment powered by hydroelectric for biodiesel. No nitrogen fertilizer required and Carrots love Tomatoes, Roses love Garlic and pests hate flax. Intercropping for food production is difficult, intercropping for fuel has potential to lower pesticide usage. Fallow with renewable electricity rather than NH3/urea from NG lowers fossil fuel usage in oilseed production. It looks like there is some research in linseed oil biodiesel.

Algae needs a lot more R&D and another decade of work and we should be concentrating on implementing lower fossil fuel farming methods and how to grow proven crops for diesel fuel without the high fertilizer, pesticide and diesel input.

I'm curious about your statement: "No nitrogen fertilizer required."

Could you explain, please?

That statement isn't exact, because whether it's stubble or summerfallow seeding, a starter blend is usually added with the seed (i.e. 11-55-00 ammonium phosphate) plus traces, but the bulk of additional nitrogen fertilizer can be eliminated on fallow land.

In a dark brown/black soil zone in Canada, like where our farm is and a lot of Canola is grown, generally you can grow an equivalent crop of cereal or oilseed on land that was fallowed the previous year compared to continuous cropping with 60-100+ lbs/acre of urea.

Legumes (i.e. soybeans) also don't require additional nitrogen fertilizer. An option to summerfallow in Canada is to rotate a legume like alfalfa.

Corn and feed wheat in continuous cropping low-till methods would be about the highest nitrogen requirement crops.

My dad would fallow about 1/3, but it is rarely done now for several reasons (diesel price, wind erosion, bank taking the farm if every acres isn't seeded, etc). One of the major issues with Canola is disease and although fallow acres are much less than ever, I would think if there is any fallow, more often than not Canola seeded in the next rotation.

Interesting. I'm not familiar with farming practices in that part of the world (you guys are up there!) but you figure you get the equivalent of 60-100+ lbs/acre of urea by leaving land fallow for a year? That's a lot of nitrogen.

Also, AFAIK, N fertilization of soybeans is still frequently recommended but, as you point out -- this may be largely dependent upon your particular crop rotation.

In the past (under hand management of crops) one planted corn and soybeans/pole beans together.

Might be something for the gardners to try.

If winter rains arrive Down Under I'm going to plant a small field of 'Tornado' variety canola on soil prepared with charcoal and small amounts of NPK (urea, phosphate, potash) and dolomite. Wide row spacing should help with bug control using a backpack spray.

However I'm swinging to the view we should use oily weeds for biodiesel, not food crops. Better still go the gasification route which unfortunately is in another league financially.

Robert Rapier: Thanks for that comment. My guess has always been, that this is just hot air.

Thanks for cross-posting this to TOD, RR. Very important, although a bit disappointing (in terms of consequences, not content).

Let me try to put this into perspective:

1st gen biofuels have been basically killed, although some just don't understand it yet. Even part of the MSM admits it these days (corn ethanol, anyone). Sure, 1st gen will get their share of subsidies and the folly will have a short run, but I hope it'll die fairly quickly.

2nd gen cellulosic ethanol is still getting the thumbs up from MSM, although seriously shot down from multiple directions here, in RR's blog

Now, 3rd gen genetically bio-engineered algal biostuff was supposed to save the planet and whatnot. Best scaling, best estimated EROEI and most potential through bio-engineering.

And now? Uh-oh.

I'm starting to get a little dizzy here.

Are there ANY bio-fuels that scale anywhere to useful amounts (1/10 of our current fossil oil consumption) with a worthwhile net energy balance and in economically sustainable way and without depleting soil/sea/ground water/climate?

Or to put it in other words:

Can we please calculate 1st a theoretical thermodynamical process maximum that a bio-fuel production process could achieve, if we could tweak out all the engineering problems.

If this theoretical maximum is worthwhile in terms of:

- CO2/methane/vapor cuts
- net energy balance
- land/logistics/water/solar/raw inputs scaling
- production costs (max 10 x viable current price)

Then a second calculation using an implementation with current known technology (perhaps with a modest 5-15% maximum performance improvement).

Isn't this already done in the initial phase? Isn't it kind of a basic exercise that one needs to do 1st?

THEN and only then should we start to look into implementing, financing, technological breakthrough attemps and theoretical perfectibility.

I think we could have avoided a lot of these follies, if the most knowledgeable people did the calculations first as a two camp battle:

1st camp: prove it that in theory it's worthwhile (with some, perhaps yet unknown, but feasible implementation)

2nd camp: prove it that in theory (using any implementation) it is never worthwhile

Currently it looks to me as without any sound theoretical understanding derived from basic laws of physics, completely silly projects get researched, funded and valuable brain power/time is wasted on things that will never mount up to anything useful (energy-wise).

Or am I completely misreading most of the news about 1st-3rd gen bio-fuel failures?

Frankly, I doubt we'll keep all the cars running, but I would personally bet more on biobutanol from pyrolysis of something like locust trees. At least we know that those technologies work.

I'd bet on locust because they are fast growing and really don't need nitrogen fertilizer. Locust is a legume that fixes its own nitrogen with bacteria. It's also a very dense wood with a high heat content:
"Nine-year-old stands exhibited the highest usable heat content 483.4 MBtu/ha for whole-tree biomass and 432.8 MBtu/ha for woody biomass." DOE Energy Citations Database.

Burying the charcoal would increase the soil quality further and sequester much of the carbon as well.

That wouldn't save our drive-through society, but it might keep some ambulances and motorcycle cops in business.

Locust trees give off toxins that make the leaves hard to breakdown by insects, and I think one of the toxin classes will effect other plants also.

Do you have any links to information on locust toxins? I work with several species, and a couple of genus'of of locust and would be interested.

As an example. I noticed how earthworms did not do well under the locust trees and the leaves did not break down. Spend 1/2 a day, found enough other data to say to myself 'stop composting these leaves' then moved on.

This is a research center for turning wood to gas

Substitute natural gas yields five times more energy per acre than biodiesel from oil plants section 4.2.1 in the left margin. The link is unfortunately only in swedish but i guess that it is possible to find the document in other languages because it is written in brussel.

One of the most important parameters must be the energy content so i used the following links and calculated the energy content for different crops. swedish links again but i just can't find the numbers in english.
MWh = Mega Watt hour
8-20 MWh/hectare/year Grain
35-44 MWh/hectare/year Energy forest (fast growing trees (salix in swedish) on farmland)
16-26 MWh/hectare/year Forest (i am not sure if forks are included in the volume)

I appreciate all the good work being done in Sweden on biomass.

People in the US have to do a few obvious things- forget about the present absurd transport system with its reliance on private vehicles of sinfully low efficiency; Then forget about the 10kW per person lifestyle in general; Then put the various energy sources where they fit best- for example, biomass for space heating and CHP.


Remember that there are other thermal power devices than diesel and spark IC engines. Then go look up the NASA space power stirling engines and note how long they last and how efficient they are. And then think of what these things could getting their heat from SOLAR ENERGY instead of isotopes.

But, truth to tell, almost no hope here (USA), Maybe Sweden???

I changed language=sv to language=en and it worked fine.


Very good! I especially like the obvious recommendation that biomass be used for heating, releasing FF for vehicles, instead of wasting time money and energy trying to turn biomass into liquids for vehicles.

This seems SO OBVIOUS that I keep wondering why people on TOD keep talking about all the hocus-pucus of biomass-to- liquids.

So, please tell me why I am wrong about this, ok? If you do, I promise to shut up about it.

Biobutanol is already available at a "barge" (bulk) price of around $3.70 a gallon according to David Ramey's site.

Gasoline is already above $3.00 and apparently headed for four by peak summer, so assuming it is possible to scale up production with some government sponsored "heavy lifting" (very doubtful!) to convert ethanol production plants it would be sensible to simply load up right now and just go as is. Once gasoline hits four, butanol is a deal, n'est ce pas?
Yes I know it ain't that simple, but I'm waiting to see who pops the balloon now that I've let it fly.

I already chowed down on the 14,000 gallon annual oil consumption figures of the island nation of Saint Vincent and the Grenadines. It would seem to me that an operation capable of producing that much is a no brainer.
For St. Vincent it would be a lifesaver as gasoline is currently NINE dollars a gallon right now.
Straight butanol at the 55 gallon drum price of $6.80 would be a frigging bargain.

I wrote to Ramey about the idea but he hasn't responded.
I'd LOVE to see him guest post here as I think butanol might have real shot...MIGHT being my hope that "other factors" don't step in with the intention of "stepping ON".

Biobutanol is already available at a "barge" (bulk) price of around $3.70 a gallon according to David Ramey's site.

I doubt that this can be bio-butanol, for reasons I will get into in an upcoming post. Probably conventional petrochemical butanol; the kind I used to make.

Mr. Rapier I am thinking it would be great to get Mr. Ramey in on TOD in some capacity for your upcoming article. I don't know about the others but I'd be thrilled to get his input and your assessment of same.

Currently it looks to me as without any sound theoretical understanding derived from basic laws of physics, completely silly projects get researched, funded and valuable brain power/time is wasted on things that will never mount up to anything useful (energy-wise).

[sarcasm, but frighteningly familiar]
Oh you silly doomers going on and on about laws of physics!
Why do you put down the triumphant power of capitalism? I bet it's because you're really nasty control-freak communists inside, isn't it!

When people actually do those computations, based on sound theoretical understanding derived from basic laws of physics, it seems to me that so far they nearly always point to the same, unpleasant answer:

It's conservation and nukes. We might get lucky, but everything else is probably just noise.
And for the love of humanity, no coal nowhere!

Uh oh.

Your perspective leaves much to be desired.

1st gen biofuels are doing just fine.

2nd gen biofuels i.e. cellulosic production paths are well underway.

3rd gen biofuels or XTL biomass->liquid processes are also well underway.

4th gen biofuels i.e. algal and genetic cocktails are -for the moment- research projects.

What everyone fails to recognize of course, is that the production paths of all the above just so happen to compliment each other. Algae biodiesel for instance, would find a ready and inexpensive CO2 feedstock source from corn ethanol fermentation while the exothermic reaction of XTL processes could provide heat for both.

Here's one of the world's first:

No, corn ethanol by itself is not going replace 10% of FF usage, however, corn ethanol facilities are the strategic lily pads for the future mass production of renewable LTFs (1st, 2nd, 3rd & 4th gen) under the integrated biorefinery construct as supported by the DOE.

Biofuels are not a failure - far from it.

Oh and BTW, Dedini announced today that they have succeeded in producing cellulosic ethanol from sugar cane bagasse for $1/gallon:

Syntec, I really appreciate you posting here, esp. considering the amount of pessimism often encountered.

However, I don't think your post addresses the crux of my post.

- Are thermodynamic ceilings calculated for various processes?
- Where are we know with current implementation tech (scaling/EROEI/true non-subsidized price)?
- How much is there room for improvement (feasibile)?

Personally I do not give a lot of value to pure economic feasibility studies (production price, investment ROI).


Way too many externalities & direct subsidies clouding the true resource/energy utilisation of the process.

A process that takes more fossil fuels as inputs (in kJ) and produces energy of lesser quality (lower density) and less in volume (liters) can be made look "profitable" or "cheap", when in fact it is a completely wasteful and stupid process.

At the very minimum the process must be analyzed for (energy quantity x energy quality) input/output. I haven't really seen analyses like these for bio-fuels processes, by the startups themselves.

Again, I'm by no means even a beginner on these issues, but a mere man-of-the-street.

However, having also lived through the period of two other tech-bubbles (biotech and Internet) I know that a lot of useless/scam projects get funded that have absolutely no basis in reality.

And I know that the majority guys funding the projects do NOT care. I know too many investment bankers to know better.

All they care about is their exit strategy with nice profits. The project can go down in flames after they exit for all they care.

So, I hope you forgive me, if I'm unfairly over-generalizingly skeptical on bio-fuels, esp. with all the data that RR keeps posting.

I see your side of the argument and I agree with you that there are those who will undoubtedly try to 'make a buck as it were'. Such is the nature of capitalism.

That said, funding for any biofuel project must run the wallstreet gamut until such time as a national directive (not long now) is undertaken to address Peak Oil for Peak as you know, portends a liquid transportation fuels crisis; the key component of which is petroleum exposure not fossil fuel exposure per se.

As such, the PIR or Petroleum Input Ratio of any proposed liquid fuel alternative is of paramount importance.

I fully support conservation, rail electrification, carbon taxes, BPHEVs and all the other mitigation wedges, however, as I recently pointed out to an ASPO colleague - North America is not Europe ergo no matter how many wedges we choose to deploy, a mass produced, renewable liquid transportation fuel(s) will be necessary.

Thanks for posting this!

the real problem seems to be our obsession with the internal combustion gasoline and diesel powered vehicle for personal transportation needs. Its not supportable with anything but unlimited fossil fuels and a perfect solution for CO2 emmissions. If one definition of insnity is doing the same thing expecting different results, then the human culture of the early 21st century is certifiable. Relying on pond scum is like relying on god for gasoline.

I think we might still look to internal combustion engines as part of the long term solution in a drive system such as a plug-in hybrid, as long we dramatically lighten vehicles and do not rely on the liquid fuels to provide energy into the system. The actual energy input would come from fission and renewable sources, if they can scale. We have a lot of potential sources of liquid fuel as long as we do not count on them for energy and as long as we realize that we are not going to have the volume of such fuels that we have now. The ICE's role in this solution would just be to lengthen the range of vehicles if we cannot develop battery technology that does not require it.


I'm with you on this!

We have inefficient car engines moving people inefficiently one or two at a time because oil has been absurdly cheap. The result is enormous consumption of oil on a daily basis. So now that oil is getting scrace we look for some other source of liquid to put in the tank.

This is dumb. Fix the inefficiencies first. Then look for a substitute liquid for the magical black stuff. Maybe we wouldn't need so much replacement volume if we reduced our consumption of oil in the first place.

I agree - internal combustion is too inefficient to survive, plus it needs very pure fuels, but we still need liquid fuels for convenience. Glossing over the technical hurdles, I would put my faith in simple closed algal reactors producing methanol (or ethanol) by metabolism from water, CO2 and sunlight, concentrated to a degree by some simple, solar-driven process, and used in robust alcohol fuel cells that could handle a relatively impure fuel. Thermodynamically it's not unreasonable: say an incident energy of 10kWh per sq m per day and 1% efficiency, that's about 3 litres per day from an area the size of a tennis court. And suddenly sub-Safaran Africa has the resource we need.

Mission: improve the soil

Oh, well, so much for that pie-in-the-sky solution.

Now that it appears that we won't be solving our energy problems with algae, perhaps somebody could do a good article on biodiesel from the jatropha plant. It's a technology that occasionally gets mentioned in the press, but very little info about it seems to be available. Is anybody actually doing this successfully? Ethanol from sugarcane (in Brazil) gets a lot of press, but wouldn't jatropha be somewhat better (since biodiesel has a higher energy value than ethanol).

Wikipedia has a brief entry about jatropha:

And I don't know much more about it than that. Since it is a subtropical or tropical plant, I guess Iowa corn farmers won't be growing it (therefore, no subsidies from Washington). Maybe that's why we never hear anything about it.


There was something in the news recently about this - my recollection is that people are just starting to think about growing the stuff on purpose, and there is a learning curve involved for figuring out the best way to do it.

Not sure - I think these are the links:

First, I have challenged the oil-from-algae community to support a fair-contest technology demonstration prize, so as to cut through the "bizarre" and "absurd" claims:

The O-Prize.

Please read it and consider suggesting it to agencies such as the X-Prize Foundation, the Gates Foundation and, if any government can be made to act responsibly, via some governmental support. The prize is structured such that no philanthropic/government monies invested would be wasted.

Second, Dr. Benemann seems to ignore NREL's claim that open ponds are _not_ viable due to low temperatures during substantial amounts of the year even in the desert areas. This, more than anything else, renders high production rates unachievable. Quoting from the report:

The Roswell test site successfully completed a full year of operation with reasonable control of the algal species grown. Single day productivities reported over the course of one year were as high as 50 grams of algae per square meter per day, a long-term target for the program. Attempts to achieve consistently high productivities were hampered by low temperature conditions encountered at the site. The desert conditions of New Mexico provided ample sunlight, but temperatures regularly reached low levels (especially at night). If such locations are to be used in the future, some form of temperature control with enclosure of the ponds may well be required.

Moreover, high productivities have never been achieved with algae without the use of raceway ponds -- which adds further to the cost-basis of oil from algae rendering it more uneconomic.

As a consequence of these realities, combined with the problem of evaporative loss, I abandoned the idea that one could economically produce oil from algae in the absence of synergistic use of the infrastructure, instead focusing on an economically plausible "biosphere" system that combines several uses and have done the preliminary pro forma net present value calculation which results in a system that produces the following annual revenue streams:

$150M for live fish
$ 70M for biodiesel
$ 50M for fresh water
$ 25M for electricity
$ 8M for salt


The calculations are available at:

using the online units calculator Unicalc Live available at:

Hi James,

Glad to see you posting here, I stumbled across your page the other day while researching solar updraft towers and was quite encouraged by your analysis. I posted a similar comment as yours on the first algae article posted here but it got little response. For those who don't know, James was the developer of one of the first multiplayer computer games called Spasim (space simulation):

I would be interested in your thoughts on a couple of points: First, one of the more common criticisms of renewable energy systems is that the energy embodied in their construction and maintenance can only be supplied by our current fossil fueled infrastructure, for example you can't build windmills with wind power alone, etc. I think the solar updraft algae bioreactor has the potential to produce enough energy, both in the form of electricity and biodiesel, to supply the capital plant needed to build another tower, which then could be used to build another, and so on. I would be interested to know if you think that idea pencils out.

Second, I was fascinated to learn that in your second release of Spasim you incorporated the differential equations used in the world simulations that were published as 'Limits to Growth'. I think a compelling world simulation presented as a game-like experience would be an invaluable tool as our various resource, population and pollution crises unfold, have you done any further work along those lines? Would you be interested in contributing to such a project?


To first order, the question of energy use for energy infrastructure production relates to the grade of energy used in construction. Since the algae biosphere updraft system produces substantial portions of its revenue from high grade forms such as electricity and biodiesel, it is a reasonable surmise that it is energetically self-constructing.

I take it that by 'grade of energy' you mean Energy Returned on Energy Invested (ERoEI). My understanding is that the basis for the criticism against most renewable energy systems is that the energy required for their construction and maintenance (embodied energy) is not returned over the lifetime of the plant resulting in a net energy loss, or perhaps break-even at best. Of course, such an accounting is largely dependent on how much of the so-called 'lifecycle' of the plant is included in the calculation, for example the energy used mining and processing raw materials, the energy embodied in the fabrication and construction equipment, the transportation infrastructure, etc. This is further complicated by the introduction of biomass into the equation which, as you already know, requires an ecological accounting of water, nutrients, etc.

I think an analysis of the embodied energy and ERoEI of the solar updraft algae biosphere concept would be extremely useful going forward, unfortunately such a task is somewhat beyond my expertise.


I guess if I were going to describe what I mean by "grade of energy" it would be dimensions of temperature*power.

Assuming construction using local materials like desert sand, the biggest energy cost of a solar updraft tower is the melting temperature and energy during manufacture of the greenhouse glass.

Using 4mm thickness and a density of 2600kg/m^3 with energy requirement of 3*2.3Mbtu per ton of glass melted,

and figures from my proforma of 1963.49 hectares per tower and 100MW the energy payback time for the highest energy component of the system construction is:

2.3Mbtu*3/ton;4mm;2600kg/m^3;1963.49 hectares;100MW?years
= 0.519621 years

or one half year's production of just the electrical output (not counting the biodiesel output). Of course there are other components which will add to the number of years for total energetic self-replication but the payback time seems very good.

Moreover, there is some prior work on this topic:

Also, we have concrete and glass, are available everywhere in sufficient quantities. In fact, with the energy taken from the solar tower itself and the stone and sand available in the desert, they can be reproduced on site. Energy payback time is two to three years (Weinrebe 1999).
6. Solar towers can be built now, even in less industrially developed countries. The industry already available in most countries is entirely adequate for solar tower requirements. No investment in high-tech manufacturing plants is needed.
7. Even in poor countries it is possible to build a large plant without high foreign currency expenditure by using local resources and work-force; this creates large numbers of jobs while significantly reducing the required capital investment and thus the cost of generating electricity.

On the virtual reality front:

We are now seeing the emergence, with systems like Second Life and others, of virtual worlds where simulation-as-pedagogy can take on a dramatically enhanced role in people's lives -- so yes I see the potential of taking the idea of Second Life type systems into many domains of education as I did with the first multi-player virtual world pedagogy in 1974. Of course, this has a lot of the aspects of fiction writing, where you might start with a set of characters in an interesting situation, and let them play out their interactions to instruct the viewer.

In the present instance, the concepts of carrying capacity, construction of agricultural infrastructure, technology investment, etc. are clearly important. Since technological civilization failed to capitalize on the boomer generation to open up the space or even oceanic frontiers as environmental safety valves, it made terrestrial options more urgent. Therefore, once the X-Prize took off and NASA started offering prize awards -- the policies to which I had pretty much dedicated my avocational life -- I turned my attentions to the urgent terrestrial problems that are resulting from the previously-mentioned failure of vision. Hopefully technologies that increase carrying capacity terrestrially can off-load terrestrial ecosystems in spite of the fact that globalization is placing ever larger economic demands on the Earth's biosphere.

The origin of human credulity toward story-tellers in the environment of evolutionary adaptation, of course, didn't include modern technologies such as broadcast media. The pathologies of letting a few people with nepotistic interests take over such an important role in mass culture will hopefully reverse itself in new media such as these virtual worlds, with the potential of representing the more positive sum character of the people rather than the zero-sum or even negative-sum character of those drawn to centralized power structures like mass media.

PS: I am indeed interested in such terrestrially-oriented educational simulations and have set up some preliminary rules, and am investigating one promising virtual world technology that may provide enough of an advantage to entice people to the world.

For what it's worth, I wrote up some notes on my ideas for the design of an 'Earth Policy Simulator' style game at This Blog. The notes are labeled 'Design Thoughts' and are numbered for sequential reading. They were written in response to an invitation to participate in a game project initiative that I received from ASPO member Dick Lawrence earlier this year. Unfortunately that project now seems to be defunct.

The notes are geared towards a single-player simulation game and not a multi-player style virtual world, the idea being that the player is placed in the role of 'World Leader' and is tasked with choosing policies that avoid overshoot and collapse. I would be most interested in hearing your ideas regarding the virtual world concept, if you prefer feel free to contact me off list at jerrymcmatqwestdotnet.


We discussed the game approach for raising Peak Oil awareness here on TOD back in 2005. What you are proposing goes several steps beyond that and when complete, will provide an excellent tool for giving the user a better understanding of the complexity of global resource management.

Do you have any targets set for when prototype or beta versions will be developed?

No, unfortunately, the project I wrote those notes for seems to be defunct now so there is no schedule or active development effort underway at present.

It would be a fairly ambitious development effort, not so much for the game engine, but in the design of the user experience. For example, it would be fairly simple to present the player with policy decisions that are more or less multiple choice, but that would severely limit the outcome of the game to a small number of winning strategies. Much more rewarding, but also much more challenging to develop, would be a game in which players could design policies from scratch. This would allow the players to 'try out' new ideas in the simulated world, ideas that the game designer may never have thought of.

If I were to blow my summer hacking in the dark on a computer game project, I would choose something much simpler, but something that still gets the depletion idea across. One idea I've been slow cooking during idle brain cycles is a game where energy is replaced with money. The player would then have the choice between Digging or Picking.

In 'Digging' the player would pay for machines which dig a hole in the ground for a narrow but very deep cache of silver dollars. The deeper the hole, or the faster the digging, the more expensive it gets which yields diminishing returns. At first the player would live high on 'fistfuls of dollars', but as the digging gets progressively more difficult, and expensive, the net dollars would diminish and the party would be over.

In 'Picking' the player would discover that an enormous amount of money is continuously dribbling from the sky, but it's spread over an immense area, and it's all in pennies. Yes, that's right, 'pennies from heaven'. It's hard work, but over the course of a day the player could pick up enough pennies to buy a good dinner for the wife and kids. And tomorrow there would be just as many new pennies to do it all over again.


I wonder why Earth Sim hasn't been revamped like others Sims products (Sim City, for instance). Will Wright seems too busy with Spore... Those Sim games had good learning values, and the financial and brand muscle to have an impact.

Good to hear about your efforts, James, I hope someone listens...

Your concept is very interesting, but the numbers were hard for me to follow. What would be the output of, say, a 40 hectare (meaning 160 acre, 1/4 section, 1/4 square mile) pond? What would the cost be? Is it covered or open? What is the optimal size, in your mind?

I think a more careful reading of James page, or even a few scant minutes spent with google, would answer your questions, but I'll give it a shot.

What would be the output of, say, a 40 hectare (meaning 160 acre, 1/4 section, 1/4 square mile) pond?

This article estimates algae biodiesel production of 1 quad per 200,000 hectares, which James used to calculate about 35M gallons of biodiesel per year per tower.

What would the cost be?

This article estimates a price tag of $700 million for a 200MW solar tower, not including algae ponds.

Is it covered or open?

A solar updraft tower has by design a large area covered by a greenhouse collector which heats the air underneath which, in turn, drives wind turbines at the base of the tower.

What is the optimal size, in your mind?

The size of the ponds is largely a function of the size of the greenhouse collector for the solar updraft tower. This article estimates a 200MW updraft tower requires a collector 7km in diameter which roughly translates to 38 sq km or 3,800 hectares. James used a smaller number of 5km diameter for the collector with the result of roughly 19.5 sq km or 1,950 hectares.

Hope this helps.


For the estimates of size in the comment above I meant to point to This PDF written by the consulting engineers on a solar updraft pilot plant built in Spain in 1982:

Broadly, to achieve a maximum output of 200 MW at an irradiance of 1.000 W/m^2, the roof must have a diameter of 4,000m if the chimney has a height of 1,500m. If black water-filled tubes are placed on the soil underneath the roof for a continuous 200MW full load 24 hours electricity production the diameter of the roof must be increased to 7,200 m. Now this solar chimney from a solar radiation of 2,300 kWh/m^2a extracts about 1,500 GWh/a, in fact a power plant!

For those not familiar with solar updraft towers I recommend their paper as a good introduction.


Although there is valuable prior art in the convection tower ideas, the concepts suffer from a serious feasibility issue.

SHPEGS Background and Prior Art has some information on both Solar Towers and Water Spray Downdraft towers.

EnviroMission lost out on the Australian Low Emmissions Technology Demonstration Fund to a Concentrated Solar Steam plant and now EnviroMission/Solarmission are attempting to get a Solar Tower built in El Paso.

The arid location only requirement of Solar Updraft Towers put them in competition with CSP/SEGS direct steam plants which are an established technology and the efficiency per m2 of solar collector is substantially lower than a steam system.

The demonstration plant in Spain had 11 acres of solar collector and a 200m tower and put out 50kW. This is equivalent to the power output of a motorcycle from 11 acres of glass plates and a 600' tower.

In a comparison, the heliostat CSP steam system recently online in Spain has 600 heliostats covering approximately half the area and puts out 11MW.

This is 200 times the output of the Manzanares Solar Updraft Tower with less solar collector area.

The flat glass collectors used in a Solar Tower would be substantially cheaper than a 2 axis tracking heliostat system, but the possible energy harvested due to buoyancy and convection is trivial compared to generating steam with the solar collection.

Nevada Solar One which is a trough style solar thermal plant came online April 2007 and produces 64MW.

The flat plate single axis collector solar steam system being funded by Vinod Khosla should have a low collector cost.

If you go through the calculations I did on the hybrid SHPEGS design, although the convection tower adds some output to the system, the possible power from causing air buoyancy with temperature changes is almost trivial compared to generating steam with the heat.

The existing solar thermal steam plants use a conventional wet cooling tower to dump condenser heat into the air as do most coal, NG and nuclear plants. A large portion of the condenser heat could be stored in underground thermal storage without affecting power plant performance and used to provide a controlled environment for algae growth.

Convection tower power generation has some value, but my opinion is that it's not a complete system on it's own. Trying to make it feasible by integrating it with algae production doesn't make as much sense as using massive thermal storage and a solar steam system to provide a constant temperature and growing algae using that heat for a controlled environment.

Integrating algae growth with combustion power generation would be a better idea than Solar Towers. A coal or NG power plant would have both low-grade excess heat and CO2.

Integrating algae growth with combustion power generation would be a better idea than Solar Towers. A coal or NG power plant would have both low-grade excess heat and CO2.

There are two basic criteria by which we may define "better idea":

1) Return on investment

2) Environmental impact

I've provided the rough financials for return on investment and it looks plausible. Please do the same for the system you propose with similar reference figures.

The environmental impact of the biosphere proposal is in its essence superior since it deals directly with scalable carrying capacity generation without environmental externalities. In other words, the single system produces the human essentials: energy, food and water, in appropriate ratios, without any obvious nonrenewable requirements -- and in so doing lowers the ecological footprint of developed-nation lifestyle by over a factor of 1000. Perhaps the externalities of coal fired plants can be reduced with your system to the point that it is environmentally competitive. Again, I've provided the numbers -- please do the same.

I didn't mean to detract from your holistic design approach and I think that you have a very sound idea by integrating a solar electrical generation system with biofuel algae and fish farming. I also don't think we should be putting our effort into coal integration and agree with you that a well designed completely renewable solar thermal system integrated with biofuel production is what we should be working on. I thought for a while whether I should have mentioned coal in my last comment, and it was probably a mistake including it.


I have spent a lot of time working on the convection tower idea and I am not a detractor of the concept, but I think it can be substantially improved upon by a more efficient electrical generation system than air convection and there are a few more substantial issues with the implementation of the solar tower.

The reference 200 MW(e) tower with a projected cost of $500-$750 million was to have 9500 acres or 38 million m2 of collectors. Assuming the plant was in the Mojave desert the peak solar insolation in June is 7kWh/m2/day or ~ 580 W/m2. The 1000 W/m2 peak claim is only for solar noon.

38,000,000 m2 * 580 W(t) = 22 GW(t) solar insolation
200 MW(e) from 22 GW(t) = 0.9% efficiency solar->electrical

Using the numbers from the article:
If black water-filled tubes are placed on the soil underneath the roof for a continuous 200MW full load 24 hours electricity production the diameter of the roof must be increased to 7,200 m. Now this solar chimney from a solar radiation of 2,300 kWh/m^2a extracts about 1,500 GWh/a, in fact a power plant!

pi*3600^2 = 40,700,000 m2 * 2,300,000 Wh/m^2a = 93,000 GWh/a
1,500 GWh/a from 93,000 GWh/a = 1.6% efficiency

Nevada Solar One was actually built and has 350 acres or 1.4 million m2 of trough collectors and produces 64 MW with a cost of $220-$250 million. I would think they aren't covering the entire 350 acres with collectors, but assuming they were:

1,400,000 m2 * 580 W(t) = 821 MW(t) solar insolation
64 MW(e) from 821 MW(t) = 7.8% efficient solar->electrical

The Solar Stirling system has a 30% efficiency claim although the collector is complicated and expensive. I haven't been able to track down the exact area of the Spanish heliostat system, the efficiency probably lands in the middle at over 10%.

I don't dispute your financial calculations or your holistic design, but the 1km tower for $500-$750M is very questionable basis data. If it cost $220-$250 million for 350 acres of trough collectors and a steam plant in a real implementation, I can't imagine 9500 acres of any type of glass collector and structure plus a 1km tower costing only 3 times that. Enviromission had some serious engineering problems with a 1km tower and scaled back the proposed height in Australia but nothing has been built yet. If you have ever been up in the CN tower, picturing a structure twice that high is difficult. Imagining it built cheaply and standing up to a 35km internal wind with turbulance and vortices is very difficult for me.

If your numbers were used:
$150M for live fish
$ 70M for biodiesel
$ 50M for fresh water
$ 25M for electricity
$ 8M for salt

but the electrical generation was brought from a 0.9% system to the level of a solar steam plant at 9%, your electrical revenue is now $250 million and for a power plant, it actually makes more money than selling the fish. :)

FYI: This group of MIT grads built a solar steam plant with hand built trough concentrators and salvage car parts and are claiming 1kW from 14m2 of trough or 12% efficiency.

Again, I think there is value in using convection towers to move air due to buoyancy, but most of the capturable energy is in the heat not the convection it causes.

I also want to say that your idea and page are valuable and interesting and I don't mean to be negative about your idea because I think it has a lot of merit, but there is a lot of misleading information around the realistic feasibility of large Solar Towers. I think your integrated idea can be improved upon if a more efficient electrical generation system was deployed.

but the electrical generation was brought from a 0.9% system to the level of a solar steam plant at 9%, your electrical revenue is now $250 million and for a power plant, it actually makes more money than selling the fish. :)

First of all, my revenue calculations are based on a 5km diameter greenhouse, not a 7.2km diameter greenhouse, due to my reliance on the design from Enviromission provided at:

So if we go with your 7.2km figure, the area of the greenhouse is doubled and the corresponding revenues for fish, biodiesel, water and salt are also doubled, so your $250 million has to compete with $566 million (not including electrical revenue). Moreover, you can claim that the cost basis of the reference system is inadequate to the task, but by increasing the scale of the system so much you have also increased the net present value of the algae biosphere updraft tower to $7 billion dollars.

Now, perhaps it is infeasible to build a 7.2km diameter greenhouse/algae pond with 1km updraft and .5 km downdraft condenser for that much money. I don't know. But viewed in those terms, it is much more plausible.

But viewed in those terms, it is much more plausible.

I agree, you have a good idea.

For a 5km diameter system:
pi*2500^2=19,600,000 m2 * 580 W(t) = 11 GW(t)
200 MW(e) from 11 GW(t) = 1.8% efficiency solar->electrical

If we go back to your numbers, but with a 9% efficient solar system, it's still 5x the output or $125 mill. It doesn't beat the fish, but it also doesn't require trying to engineer 1km of tower.

These numbers that EnviroMission/SolarMission are using are for extreme arid locations. The location dependency means that to get anywhere close to the output they are claiming and grow algae, you need access to a lot of water in the desert. This is a contradiction of concepts. Also, the arid only location will require a major electrical transmission infrastructure. So, by attaching your good idea to the solar tower, you have to build both aqueducts to get the water to the desert and electrical transmission to get the power back out.

Enviromission/Solarmission couldn't obtain IP rights to concentrated solar steam, but they did for their Solar Tower design.

The steampunk system the MIT grads put together out of cheap collectors and a power steering pump for a power turbine, they got 1kW peak from 14m2 of collector. If that was brought up to 50x to the Manzanares sized system, it would only cover 14m2*50=700m2 and put out 50kW peak matching the 50kW they got from 46,000m2 of collector in the Solar Tower in Spain. This is from a system using a salvaged hydraulic vane pump and sheet metal parabolic troughs.

I don't have any financial stake in this.

If you look at the Solar Tower talk page in Wikipedia, it has gone through mediation and has had several episodes of a sock puppet filling the encyclopedia with marketing. The archive has an Enviromission employee accusing editor JDH of sabotaging the Australian Demo Fund bid by factualizing the article and removing the hype. All they have done in Australian is bought a sheep farm for $1 million, and now they are trying in the US.

I learned very early and painfully that you have to decide at the outset whether you are trying to make money or to make sense, as they are mutually exclusive.
- R. Buckminster Fuller GRUNCH of Giants, 1983

If an idea like yours was used to integrate algae with solar thermal, but a more efficient solar thermal system that was location independent was used, it starts to hold a lot of promise.

What I am proposing by using concentrated solar to power an absorption heat transformer, the output of the solar collectors can be at least doubled, by extracting additional heat from the air. If a much shorter convection tower is used, the buoyancy principle of changing the air density by changing it's temperature and humidity allows for efficient air movement and also can generate a small amount of base load electricity (10% of the total system).

This is a system like this:

I tried to be very conservative with thermal->electrical performance of the binary steam portion and used 2-4% in the various calculations, but in this system, the thermal output of the solar collectors is at least doubled by the heat extracted from the air.

I find that quoting peak output in solar and wind systems to be very misleading and although peak output is established for traditional nuclear or coals plants, I think it is used in intermittent systems as a marketing gimmick.

The Toronto Exhibition Solar PV demo live stats gives a good idea of how much power a 100kw peak solar system actually produces in real operation.

Using Wh/day notation and not solar noon peak numbers, I came up with output statistics for the SHPEGS system in a Canadian/Northern US climate of:

  • Summer wind turbine electrical output: 4.8 MWh(e)/day (constant)
  • Summer heat recovery turbine output: 53MWh(e)/day
  • Total summer electrical output: 58 MWh(e)/day
  • Winter electrical output: 26 MWh(e)/day
  • Thermal storage: 2.6GWh(t)/day (summer)
  • 100-meter tower
  • 250,000 m2 trough concentrated solar collectors
  • Large thermal storage (vertical bore-hole 100m deep 1km x 1km=100,000,000 m3)

If a system like this was integrated with greenhouse algae production, it no longer is arid location dependent, the average 24h/365day electrical output is close to 5% efficient for the solar collectors and it puts out substantial electric power in the winter in a northern location. It also doesn't require a high tower and can be scaled from the bench to the mega-project and that means it doesn't need a billion dollars of investment to get the first one built.

Again, I think you have a good idea, but you are basing the Solar Tower on marketing hype that is there because someone is trying to raise a billion dollars of investment and talk a power company into a long term subsidized contract.

Here are the engineering constraints created by the environmental goal (reproduce human essentials of energy, food and water in approximate ratios required by developed world standards of living, in a system that has residential areas incorporated) of the algae biosphere:

  1. Maintain the algae growth medium at a temperature compatible with high per-area productivity.
  2. Drive the algae growth medium -- probably via raceway shaped ponds -- approximately in proportion to the solar flux.
  3. Scrub the atmosphere of CO2 for some of the carbon input.
  4. Recapture most of the water otherwise lost to evaporation in some sort of condenser.
  5. Produce at least 2W/m^2 of electricity. (People can get by with a lot less electricity if they're around water to buffer heat.)
  6. Some substantial area is dedicated to algae grazing fish ponds maintained at a viable temperature for those algae grazers.
  7. Some substantial area is dedicated to human habitation near to the facility so that transport costs are minimized.

If there are better ways of meeting these constraints than the updraft/downdraft condenser then that's wonderful!

However, just to clear up some misconceptions you have:

The aqueducts you describe don't need to be that big as a percentage of the cost since the water is being recycled internally through evaporation/condensation.

The location of the biospheres is not constrained to arid locations, even if they use updraft towers, because the power is really generated by a downdraft due to condensation of water.

If people are colocated with the fish ponds, as seems likely given the construction of artificial lakes in places like Arizona for high value real estate, then the transmission lines you talk about are not necessary as the electric power output is about what the colocated population needs for developed nation standard of living.

That said, I'm not happy about any system that requires big centralized structures. In terms of social impact, I consider such centralized structures pathologies. BUT they're tolerable if they provide the enormous reduction in ecological footprint seemingly offered by such systems -- and having 200,000 households per tower, arranged at the perimeter of a circle, does at least limit the social pathologies associated with inner cities.

I agree with almost all of your points except for wanting to live in a desert.

There is a lot of sparsely populated areas of the earth and the middle of a desert is about my last choice. Saskatchewan is the size of Texas with a population of 1 million. The southern half is very fertile and the north has a Boreal forest the size of Germany with a few thousand people scattered through it. Along with the global majority of potash and uranium, 1/3 of the oil and gas in Canada, coal there is enough farmland to grow 12 million tonnes of wheat and almost as much Canola along with substantial feed grains, dairy, beef, poultry, etc.

I don't relate to the frying in the desert idea, but that's probably my subjective opinion.

A minor clarification:
I didn't say that you couldn't build a solar tower outside of an arid location, I said that the numbers they are using are based on arid 7kWh/m2/day peak locations. If the system is built in a lower insolation area you have to use that locations insolation to calculate feasibility.

NASA has the Global Surface meteorology and Solar Energy Data available online (free registration).

Well we're addressing different problems. I'm interested in reducing the ecological footprint of developed nations -- not in finding ways of exploiting more natural ecosystems. The big overpopulation problems are in the tropics and subtropics, not in Canada. As those countries develop -- as they are -- it is mandatory to produce systems that can support developed-world standard of living with minimum ecological footprint. This isn't a hypothetical problem. Go buy some gasoline today.

As for "arid locations" understand that there are a lot of very humid areas with high insolation and that the reason the Enviromission guys avoid those areas is because their system has no downdraft condenser with which to:

1) Recapture latent heat of vaporization present in humidity.
2) Provide potable water.

Those are good points.

Look through SHPEGS Tropical Calculations when you get a chance. I haven't been concentrating on tropical environments, but I think the calculations are correct and there might be some ideas you can use. It's amazing how much heat is in humid air and how much water you can condense out of it.

On another topic:

One of the concepts an acquaintance has been working on with algae farming has to do with polar bears and fiber optics. Apparently polar bears have a dark skin under the fur and the coat appears white but the hair is translucent. The effect is that the coat transmits solar heat to the skin like a fiber optic cable.

Algae farming attempts have been using shallow pools because the solar energy only penetrates so far. In an open pond, evaporation and temperature control are problems. The concept is to use underground thermal storage, deep and narrow underground algae tanks and then glass rods down through the goop to distribute sunlight into the controlled temperature environment. Lowering the surface area for the volume fixes the evaporation problem. I would think keeping the light transmission rods clean would be an obstacle and I don't know enough about the required light spectrum and whether it would transmit well, but the concept is very interesting. This type of system would work well with our SHPEGS idea and make it possible to grow algae in sub-zero climates with sufficient thermal storage.

And an unrelated topic:
Several years ago I spent quite a bit of time writing a Battlezone clone in vlisp in Autocad and from what I can remember I had most of it completed. What I can't remember is why.

If you read over Benemann's objections to photobioreactors you'll see him essentially commenting on the approach you are talking about.

The light distribution problem is dealt with in algae farms by driving the medium during sun exposure so that cells are periodically submerged and self-shaded. I suggest you buy a culture of some popular species like arthrospira platensis from Carolina Scientific and experiment with it as I did. Read over my experimental log in the yahoo "oil from algae" group.

I abandoned the idea that one could economically produce oil from algae in the absence of synergistic use of the infrastructure, instead focusing on an economically plausible "biosphere" system...

Have you posted this here before? I have read about your idea somewhere; I just can't remember where. But at the time I thought such a system - like a fish farm with a biodiesel, etc. byproduct, seemed a lot more feasible than just growing and harvesting algae.

No, I haven't posted the idea here before.

The problem is most people need to, on the one hand, get past the euphoria that oil from algae alone is going to save us, and on the other hand, get past the "giggle factor" of algae as a crucial technology. A colleague pointed me to this article, recognizing the opportunity it presents to renew rationality for this technology.

Robert, thanks for posting this. I haven't had a chance to read the ASP report (I plan to), but maybe you can answer a question or two:

The two issues that seem to me to be very problematic when talking about algal biodiesel are:

  • What sort of land area would need to be devoted to ponds?
  • What would you use as a feedstock?
  • My understanding is that a substantial area would need to be devoted to ponds ("a mile wide and an inch deep" to be effective) and I would presume (though I could be wrong) that a fairly "rich" feedstock would be needed -- municipal sewage, animal manure, etc. Taken together, you are talking about substantial impacts to ecology and the human environment.

    This is why I've assumed that some sort of enclosed bio-reactor would be the only way to go, but John Benemann obviously disagrees.

    There's a reason that municipal waste systems universally use cement ponds. You can't afford anything else.

    The biggest problem I see with open ponds are species contamination from wild algae spores. This would necessitate maintaining large stocks of your purebred high-oil algae and having to empty and scrub your algae pond often when contamination from the wild species got too high.

    Also (I haven't read the Closeout Report yet), the algae biodiesel cheerleaders such as Prof. Briggs never-mention problems with seasonal factors, such as temperature and day length. How are you going to have a productive algae biodiesel operation in Wisconsin, or Arizona for that matter? Algae grows naturally in both those climes, but does high-oleo algae and how long is its productive season in both climates?

    I live next to a large, very eutrophic lake, and until recently we had massive algae blooms and busts. The county bought a boat to harvest algae from the surface of the lake when there were bad, stinky die-offs. The harvested algae was very useful as a soil ammendment for farmers -- but not much else.

    The local geothermal electricity plants depleted their natural aquifers, so they contracted with the sanitation districts to pump treated sewage into the mountain. The algae blooms are much less severe now and we get electricity from our toilets!

    Anyway, I just don't see anything approaching massive algae biodiesel production and I'm no expert.

    Hi capslock,

    I personally think that the use of natural vectors (non-GMO bacteriophages) to control culture contamination could be used to manage open pond contamination. Its a concept taken from phage therapy, except your host is the algae pond now, instead of the human body. You continuously dose the open pond with phages that attack the most invasive microbes/wild algae into the culture solution to prevent the invasive species from taking over the pond:

    With contamination problem addressed, you'll need to look at how to prevent open pond culture condition fluctuations (Culture crashes due to swings in culture pH, conductivity, temperature, light intensity etc). Controlling these conditions in open ponds is VERY challenging. Heck, even controlling a closed-system bioreactor is hard. Just ask the people doing anaerobic digestion research!

    Algal biofuels would not be an easy task to realize.

    Ray Huang

    That Wiki article must have been written by a bio-tech venture capitalist. No attention was paid to the biggest obstacle of "phage therapy"--resistance by the target organism. This notion has been kicked around for 80 years (ever read Arrowsmith?) and except for an immediate knock-down in bacterial titre, there is little long term affect other than a colony of resistant organisms

    we do have a colony of resistant organisms now called MRSA and VRE resulting from antibiotics use, hehehe, so what's the difference?

    Yes, phage therapy has been around since the 1920s, I'm not disputing that. But I don't believe the therapy has been perfected until the recent years.


    From the NREL report:

    Over the course of the program, efforts were made to establish the feasibility of large-scale algae production in open ponds. In studies conducted in California, Hawaii and New Mexico, the ASP proved
    the concept of long term, reliable production of algae. California and Hawaii served as early test bed sites. Based on results from six years of tests run in parallel in California and Hawaii, 1,000 m2 pond systems were built and tested in Roswell, New Mexico. The Roswell, New Mexico tests proved that outdoor ponds could be run with extremely high efficiency of CO2 utilization. Careful control of pH and other physical conditions for introducing CO2 into the ponds allowed greater than 90% utilization of injected CO2. The Roswell test site successfully completed a full year of operation with reasonable control of the algal species grown. Single day productivities reported over the course of one year were as high as 50 grams of algae per square meter per day, a long-term target for the program. Attempts to achieve consistently high productivities were hampered by low temperature conditions encountered at the site. The desert conditions of New Mexico provided ample sunlight, but temperatures regularly reached low levels (especially at night). If such locations are to be used in the future, some form of temperature control with enclosure of the ponds may well be required.

    As a point of reference, Roswell gets about 7 kWhr of solar insolation at max, which is the energy equivalent of about 650ml of #2 fuel oil. Assuming that the algae is half oil, it might yield about 30ml of it--roughly 5% efficiency on solar energy conversion to liquid fuel (not counting the methanol and other energy input to make biodiesel) with CO2 injection.

    *clap* *clap*

    A good week on TOD for articles.

    Too bad such a level can't be kept up :-(

    It's too bad. I thought algae had more promise than you indicate.

    As to the Greenfuel Technologies claims, take a look at the ThinkEquityPartners LLC Greentech Summit page. Perhaps there are some readers of The Oil Drum who believe that Silicon Valley VCs getting involved in alternative energy stategies is a good thing. I am not one of those people. I would remind those readers that these are the same people who brought you the "Dot Bomb", among other fiascos. I also believe that many of them don't know the difference between a hydrocarbon and an ipod.

    Furthermore, Greenfuel Technologies and other such ventures are trying to raise money, so, of course, they are going to hype the hell out of whatever technology solution they happen to be selling. If they raise enough money, they can stay in business for a long time without necessarily doing much. In order to be successful, these start-ups need to

    1. sell the idea that they have a miracle technology
    2. have a convincing business plan
    3. define their "Exit Strategy"

    Now, given Dr. Benemann's remarks here, you would think -- if you are a science type like me -- well, there's no way in Hell they can sell this! Unfortunately, due diligence on the part of would-be investors is not all it could be -- and energy is HOT! It gets hotter everyday as the gasoline price goes up. Ultimately, everyone involved is trying to make money. This can be accomplished the right way with a solid, commercially viable technology -- some of the solar stuff looks good -- or it can be done the wrong way by bamboozling people and making sure that money changes hands. The latter is more and more the American way of business.

    I'm truly sorry to see that biodiesel from algae is an R&D hit or miss project -- likely miss. And remember, it's good to have a nice logo.


    It may stumble onto something useful (E Bay) but ya - successful sites such as Myspace and Craigslist did not start from that fold.

    Good work Robert and John.
    I think the problem is that most Venture capitalists are not thermodyanamically literate. Also Dr Dimitrov mentioned that some investors invest in many many of these projects with expectations that if even one out of 10 of these are successful they will cut even ( 10 bagger?). Very few have the intellectual capacity to dissect these companies. Sprott asset Mgmt is one that comes to mind.They have an amazing track record.

    absolutely agree, this is exactly the story with GreenFuel. I've written in my blog.

    When scientific illiterates like Jennifer Fonstad from DFJ make investment decisions, things are either going down the drain or eventually switch to the "Find the Bigger Fool" business model.

    The sad part is that it's at the expense of other people's money. The VCs get paid a fixed percentage of assets under management, while their lapdog CEOs (like Gary Bullock in this case) get paid six-figure salaries. At the end of the day the entities whose capital is being wasted are left holding the bag - pension funds, private foundations, universities, etc.

    There is some turmoil starting to brew, however, take a look at this:

    Hello Dr. Dimitrov,

    Nice to see you posting here. Any thoughts on the potential of James Bowery's approach, as described above? I think if you were harvesting the algae as a by-product, and you were not installing a lot of capital specifically for the algal biodiesel, such an approach could be feasible.

    A colleague and I just submitted a paper to Science calculating the EROWI (energy return on water invested) It basically shows that with the exception of solar and wind, most alternative fuel technologies use vast quantities of water vis a vis their fossil fuel counterparts (between 10 and 100 times more). This will severely limit the scope of biofuels production, but water is one of those borderline 'commons' resources so the market hasnt correctly factored it in.

    In reference to Daves comments above regarding interest in energy and hype, etc., the last thing people want to hear is that we need to change the consumption paradigm - so anything that is presented as an 'alternative' or 'replacement' to fossil fuels will appeal to their underlying belief systems. Work at theoildrum, and other areas (like ecological economics) are gradually painting a picture that the supply of all sources will not be there to meet the demand, unless the demand itself changes, by voluntary destruction, or involuntary destruction, or by the voluntary 'construction' of a less liquid fuel, less transport-centric society. This last option is too radical as of yet to appeal to too most entrepreneur types.

    Nice concept. Good luck with the paper.
    Keep us updated.

    Yep. Still desperately seeking the free lunch aren't we. That's the basis for a lot of conflicts. Especially when the promised lunch doesn't arrive.

    EROWI - Hrm, another idea to track.

    My Hazelnut bushes look better and better it seems as a way to obtain oils for fuel. Cept that the oil is worth $65 a gallon.

    I'm continually amazed how desperate people are to keep their damn cars.

    I agree that some of the scientific articles are borderline delusional about the prospects for algal hydrocarbon production. The "bioreactor" (too expensive) and "desert saltwater pond" (excess salinity) ideas are particularly troubling.

    Even if we grew in freshwater ponds, the contamination problem would be troublesome. Not to mention water loss. I suppose we could engineer "RoundUp Ready" microalgae, but at what environmental cost?

    Do any of you have any opinions on BTL/TDP of marine-grown algal biomass? Choren in Europe has a plant running on land-grown biomass. Seems like a waste of land that could be used for food.

    My question to Dr. Benemann...

    If you note from the p.247 in 'A Look Back' we find,

    "The major conclusion of these analyses is that microalgae production for fuels is currently not limited by engineering designs, but by the many microalgae cultivation issues, from species control in large outdoor systems to harvesting and lipid accumulation to overall productivity. Future R&D must focus on these biological issues as a primary research objective, in the quest for low-cost production processes."

    In this context then...

    Do you know what $/bbl oil price was assumed by the NREL research team for deriving their production process cost comparison?

    Robert, you might want to look at a different bio-diesel operation: Nova Biosource Fuels, a public company, symbol NBF, has a couple of plants up and operating using a non-water process for separating various inputs into diesel and glycerin. Their aim is to use high fat content animal waste products. They claim a significant cost advantage over traditional water process methods by using a high temperature, high pressure patented process. They say that 70% of the fuel needed for their process comes from the output of the process itself.

    Should we return to the steam car? Then we wouldn't have to convert anything, just burn it under the boiler!

    For a vehicle which operates for several hours at a time steam has its advantages. The time taken in building boiler pressure has been a drawback and wastes energy that could be used moving the vehicle on short trips. Some systems can shorten warmup times at the expense of thermal energy storage. But if you have a cheap source of fuel inefficency may not be much of a problem.
    I see the best use of biomass is for generating electricity for charging vehicle batteries. All the inedible parts of plants could be used as well as yard, forestry waste, and MSW.

    How, and at what cost, do you plan to collect everyones grass clippings, etc., and transport it to a generating facility? Or will everyone have their own grass-burner/generator?

    You would be hard pressed to find a community that does already have a trash collection system. Waste to power systems already exist in many cities. Experiments on the collection of dedicated energy crops have been carried out in Iowa and concluded that at current yeilds and coal prices it just didn't pay. Small powerplants are common in this part of Iowa and could be fed gasified silage and corn stover if proper equipment were invested in.

    Adam Rybczynski

    What type of environmentally safe methods of transportation do you think the United States can use to reduce dependency on foreign oil?


    ... for the convenience of TV, you can only be one of two kinds of human beings, either a liberal or a conservative. -- Kurt Vonnegut

    Adam Rybczynski

    What type of environmentally safe methods of transportation do you think the United States can use to reduce dependency on foreign oil?

    Nuclear-electric rail. Nuclear- or solar-generated boron internal combustion.

    --- G. R. L. Cowan, former hydrogen-energy fan :
    oxygen expands around boron fire, car goes


    Excellent post Robert!

    While I would like to see more work on growing algae for fuel, there are so many engineering hurdles that it is a long way off, if ever. Combined uses (fish food, etc., with maybe some oil or methane from byproducts) for algae from ponds is more likely. Even that will take some time.

    Good post, RR.

    I continue to believe that the best application of biodiesel is small-scale oilseed crop production and pressing right on the farm for use on agricultural equipment. This approach would eliminate the round trip from farm to factory to farm, and thus boost the EROEI considerably.

    Perhaps a Biofuel Railroad in the farming areas ?

    The following is the text of a Press Release from the Alabama Governor's Office (from exactly one month ago today, Apr 18). Apparently, this is all the rage.

    I appreciate Dr. Benemann's balanced evaluation of this, to wit: keep with the research, it can only help, but stop making with the wildly optimistic claims.

    MONTGOMERY—Gov. Bob Riley has awarded a $10,000 grant to Auburn University to determine the possibility of turning pond scum into biodiesel gold.

    The grant will enable the university to conduct a study to determine the economic and technical feasibility of cultivating pond algae commercially as a source for biofuel.

    “Alternative fuels help us protect our environment, reduce our dependence on foreign oil and give an economic boost to our farmers,” Riley said. “I am pleased to provide funds for this study which could be the first step in making Alabama’s farmers leaders in producing and selling a new source for biodiesel.”

    Current biofuels are produced mainly from corn and soy. Because corn and soy are already in high demand as a food source, researchers foresee shortages and increased costs as the use of biofuel grows. Pond algae could be a viable alternative because it contains nearly identical vegetable oil and it thrives in shallow ponds on carbon dioxide, wastewater and solid agricultural and industrial waste. Also, algae can produce 4,000 gallons of vegetable oil per acre in properly designed ponds each year, compared to 43 gallons per acre for soy, researchers said.

    The study will examine the growth rates of algae in Alabama and the technology currently available to harvest the algae and extract the oil needed for biodiesel. Researchers will visit facilities that use and harvest algae and interview manufacturers to determine the latest equipment available for algae farming.

    If the results of the study are favorable to producing algae commercially, the university will then start a two-acre pilot pond and develop one or more 10-100-acre demonstration ponds.

    The Alabama Department of Economic and Community Affairs will administer the grant. Riley awarded the grant from oil overcharge funds, which were paid to Alabama and other states as restitution for oil company violations of federal oil pricing controls in the 1980s. Riley informed Auburn president Ed Richardson that the grant had been approved.

    Quoting from another blogger comment regarding this:

    "This is the most baffling sort of behavior I think I've ever seen. Reading the last line tells you that you have the potential to produce about hundred times the fuel per acre and you can't scrounge up more than ten grand to look into it? A wee bit disappointing to say the least. But without national leadership towards energy independence I guess we are going to have to go with what we've got, no matter how meager it is."