Cellulosic Ethanol vs. Biomass Gasification


There is a lot of government funding available for cellulosic ethanol processes. So, I have developed a new cellulose conversion process. I plan to get some of that government funding and apply for a patent. The invention is a personal cellulosic biomass reactor. In the first reaction step, the cellulose is gasified to CO and H2 (syngas). In the second step, there are several options for the syngas: produce methanol, ethanol, Fischer-Tropsch diesel, or combust it for heat or electricity. I chose to combust for heat, which occurs very rapidly following the 1st step. The combustion products are CO2 and water, but the CO2 that is released is equivalent to the CO2 that was taken up by the biomass while it was growing. It is therefore carbon neutral with respect to greenhouse gas emissions. I am hoping to get some government subsidies, or possibly Silicon Valley startup money for my invention. You can see a picture of it below.

Personal Cellulose Reactor

And there you have an example of how technical jargon can be confusing to people. The media don’t seem to be very clear on just what cellulosic ethanol is (other than the fact that it will “save us” from our fossil fuel addiction), so this essay will compare and contrast two options for generating alternative energy: Cellulosic ethanol and biomass gasification.

What is Cellulosic Ethanol?

The media - encouraged by confused statements by various ethanol advocates - has liberally applied the "cellulosic" label. It has become a buzzword. This is the same thing that has occurred in the field of nanotechnology. Because lots of research funding is available for nanotechnology, things like ultra-fine powders are now being called nanotechnology, even though this is probably not the vision most of us have of nanotechnology. This trend is happening because there is a lot of money flowing to the nanotechnology sector. If you can call you ultra-fine powders “nanotechnology”, then you stand a better chance at receiving some of those dollars.

This brings us to some of the claims of breakthroughs in "cellulosic ethanol" technology. However, one of the "breakthroughs" - biomass gasification - has been around for decades, and the technology is quite different from what is commonly denoted as cellulosic ethanol. It is not completely clear to me why some advocates are so eager to blur the distinction. Perhaps the law is written such that there is a danger of not receiving ethanol subsidies if a combustion process is used. Perhaps they want to be the first to claim commercial success of "cellulosic ethanol." Perhaps they just want to give the public and the government the impression that great strides are being made in cellulosic ethanol technology, thereby encouraging more money to flow in that direction.

While cellulosic ethanol has only recently gained buzzword status, the term has been around for decades. The historical definition of the term implies certain particular process steps. There is some variance from process to process, but the things that are common are that the cellulose in the plant material is broken down into simple sugars, and then the sugars are fermented into ethanol.

More money than ever before is being poured into cellulosic ethanol, but there are multiple hurdles that have proven difficult to overcome. For a good layperson's overview of the process, I recommend an article from the Chicago Tribune: Beyond corn: Ethanol's next generation. I think the article paints a balanced picture of the technology. In brief, there are three major hurdles that have proven challenging to resolve.

The first is that plants have evolved defense mechanisms to prevent the cellulose from being easily broken down. Cellulose is actually a polymer - a long chain of connected sugars, and it is intermingled with hemicellulose and lignin. Cellulose provides structural strength to the plant walls. If it was easily broken down, microorganisms could attack the plants and limit their structural stability. What this means is that the cellulose must first be broken down with steam or a strong acid into component sugars that can be fermented, and this adds to the production costs. It is primarily this step that differentiates cellulosic ethanol from grain or sugarcane ethanol.

The second hurdle is common to all ethanol fermentation processes, but not to gasification processes. The ethanol that is produced in a fermentation process is highly diluted with water. In fact, the ethanol produced from fermenting grain typically makes up only 15-20% of the solution, with the remainder being mostly water. For cellulosic ethanol, the picture is much worse. The crude ethanol in this case is typically less than 5%, with the remainder being water. Separating water and ethanol is a very energy-intensive process. Even where the EROEI is highly favorable, as is the case with sugarcane ethanol, the distillation step takes up a substantial amount of energy. While the distillation energy in the case of sugarcane is provided by burning the bagasse, separating out that much water is still a major energy sink.

The final challenge for cellulosic ethanol is that it takes a significant amount of biomass to produce the ethanol. As the nearby biomass is consumed, trucks have to travel farther to bring biomass to the refinery. This adds to the energy inputs, and worsens EROEI. According to the previously referenced Chicago Tribune article:

Richard Hamilton, CEO of Ceres Inc., Hamilton termed this "the tyranny of distance," a major cost issue for would-be producers of cellulosic ethanol. If a refinery needs tons of biomass to produce fuel, he said, "by the end of the year you're driving your truck a long way to get that wheat or corn stover."

Some proponents don't appreciate that there are multiple challenges in bringing cellulosic ethanol to market, and that these challenges won't be easily solved. When asked about how long it would be before the challenges are resolved, Hamilton added:

"Trying to predict technology trends is a fool's game," he said. "I wish I could put my finger on just one bottleneck. But it doesn't work that way."

I don't want to paint too grim a picture of the future for cellulosic ethanol. It is possible that all the hurdles will be overcome. But I also don't want to present an overly optimistic scenario in which multiple bottlenecks are merely hand-waved away, and successful resolution is presumed. The challenges are well-understood. There just isn't a clear path at this point to solving them all, and a process with multiple challenges will face a lower probability of success.

What is Biomass Gasification?

Biomass gasification is different from cellulosic ethanol in at least two major respects. First of all, it is a combustion process, not a fermentation process. As a combustion process, it can be self-sustaining once the combustion is initiated. It does not require continual inputs of energy as is the case with a fermentation process. The products of biomass gasification are syngas and heat, if the reaction is operated in an oxygen-deficient mode, or CO2 and steam (and much more heat) in the case where sufficient oxygen is supplied. In the case of the former, the syngas can be further reacted to make a wide variety of compounds, including methanol, ethanol, or diesel (via the Fischer-Tropsch reaction). A biomass gasification process followed by conversion to a liquid fuel is commonly referred to as a biomass-to-liquids (BTL) process.

However, there is one other major factor that differentiates biomass gasification from cellulosic ethanol. Biomass consists of a number of different components, including cellulose, hemicellulose, and lignin. In the case of cellulosic ethanol, only the cellulose and hemicellulose are partially converted after being broken down to sugars. The lignin and other unconverted carbon compounds end up as (wet) waste, suitable for burning as process fuel only if thoroughly dried. Conversion is limited to those components which can be broken down into the right kind of sugars and fermented.

Gasification, on the other hand, converts all of the carbon compounds. Lignin, a serious impediment and waste product in the case of cellulosic ethanol, is easily converted to syngas in a gasifier. The conversion of carbon compounds in a gasification process can be driven essentially to completion if desired, and the resulting inorganic mineral wastes can be returned to the soil.

Iogen's Cellulosic Ethanol vs. Syntec's Gasification Process

Gasification processes are of course not limited to biomass. In fact, biomass is currently the last feedstock of choice for economic reasons. It is much easier to transport natural gas and feed it on a continuous basis to a gasifier. In fact, most syngas in the U.S. today is made from natural gas. Coal is another option for gasification, and coal gasification is currently the dream of Montana Governor Brian Schweitzer.

While natural gas is easier to handle, and coal is cheaper, biomass is the only option capable of producing sustainable energy and mitigating greenhouse gas emissions. It is therefore the option that is most desirable from an environmental perspective. It is also a better option than most other "renewable" alternatives like corn ethanol or cellulosic ethanol. The conversion is much higher for gasification, and the energy return will undoubtedly be better because the product won't need to be removed from an aqueous solution.

Compared to cellulosic ethanol, there are few technical challenges to solve with biomass gasification. The problems with biomass gasification aren't technical, they are economic. According to the EIA's Annual Energy Outlook 2006, capital costs are $15,000-20,000 per installed barrel for a conventional oil refinery, $20,000-$30,000 for an ethanol plant, around $40,000 for gas-to-liquids (GTL), around $60,000 for coal-to-liquids, and around $120,000-$140,000 for biomass-to-liquids.

Capital Costs of Fuel Facilities

Source: EIA Annual Energy Outlook 2006

The reasons for this should be obvious - it is much more difficult to handle biomass than to handle natural gas, for instance. Until we are willing (or forced) to pay a penalty for using fossil fuels, or are willing to pay a premium for renewable energy, biomass gasification is going to be passed over in favor of lower capital options. In the long-term, though, biomass gasification has staying power as an option for using biomass as a transportation fuel.

Vinod Khosla and Kergy

What actually prompted this essay were the media reports of Vinod Khosla's latest alternative energy venture. This has been hailed as a breakthrough in cellulosic ethanol. While some may consider this a subtle distinction, I think it is very important that people understand the difference. It may make sense to preferentially fund gasification options over cellulosic ethanol options, but this will be more difficult if the public doesn't understand that there is a difference.

A story in Venture Beat brought Mr. Khosla's new venture to my attention. The company is called Kergy (recently renamed “Range Fuels”), and details were discussed in a story in Wired written by Vinod Khosla. Mr. Khosla explains:

In the corner of an unmarked warehouse tucked away in an industrial neighborhood north of Denver, a new company called Kergy has what is, to my knowledge, the first anaerobic thermal conversion machine (which explains why Khosla Ventures is a seed investor). It's a 6- by 4-foot contraption that stands about 8 feet high. It looks vaguely like a souped-up potbellied stove. But it runs cleanly enough to operate indoors.

Kergy's machine is special because it makes cellulosic ethanol through anaerobic thermal conversion rather than through fermentation or acid hydrolysis. It does not need organisms or enzymes to do its work. Biomass is heated in an oxygen-free environment to produce carbon monoxide and hydrogen. Once that happens, "the world is your oyster," says Bud Klepper, the engineer who invented this device. The carbon monoxide and hydrogen are then reconstituted into various alcohols - like ethanol. Better still, fermentation and acid hydrolysis can take days to occur, but thermal conversion breaks down organic matter and converts it to ethanol in minutes.

And here's the really exciting part: Because all organic matter contains carbon, Klepper can make ethanol out of cellulose or any form of organic matter. This means the usual suspects such as corn, switchgrass, sugarcane, and miscanthus but also any waste product such as wood chips, paper pulp, cow manure, and even human waste. Municipal sewage has been tested already, as has hog manure. "We could double the ethanol output of the Mead facility," Klepper says. It's a big leap forward on the biohol trajectory, and it is right in front of us.

In back of Kergy's warehouse, workers are busy putting the finishing touches on a beautified and expanded version of his original thermal convertor. The new one is made out of lustrous red I-beams, shiny metal tanks and coils, bright blue metallic joints, and a porous metal-grating floor. The whole thing is 14 feet high, 40 feet long, and 25 feet wide and is capable of producing 15,000 gallons of ethanol a day. And the machine can be scaled for far more capacity.

I knew this technology has been around for a while, so I looked up Klepper's patents. After reading through the claims, it wasn't clear to me what differentiated Klepper's version from the patents that came before (although I did notice that the temperature was pretty low for a gasification). Sometimes it boils down to very subtle differences in the claims, so I wrote to Mr. Khosla asking for some information:

Hi Vinod,

Just finished reading the Wired essay. Of course I disagree with several of the things you wrote, but that isn't the purpose of this e-mail. What I am particularly interested in are the claims on "anaerobic thermal conversion." Some people have been calling this cellulosic ethanol, but that's really a misnomer because it is a completely different process. It is actually biomass gasification to produce syngas, a technology that has been around for at least 30 years. So it certainly isn't "the first anaerobic thermal conversion machine." Lots of people have done this, just not commercially. The technology for turning the resulting syngas into methanol, ethanol, or even diesel (via the Fischer-Tropsch reaction) has also been around for many years.

As I am sure you know, the reason this hasn't been done commercially before is the high capital costs per barrel of product. But I just did a patent search, and saw that Klepper has been issued a patent on the process. It just isn't clear to me what distinguishes his patent from those that came before. Do you know? I am not trying to downplay the invention; differences in patents are often very subtle. But I am trying to determine how his patent differs from all of the other biomass gasification patents.

I will say that I believe you are on the right track with biomass gasification. I have never had any concerns about this technology, and I believe that this is clearly the future. I just don't know if it will be commercially viable without subsidies or mandates, because it is much easier (and far less costly) to do the same process with natural gas (GTL). But it is certainly more efficient to gasify biomass than it is to ferment it. I think you will find that it would be far more efficient to turn the syngas into diesel, but you might lose out on the subsidies. I guess if the government accepts this process as cellulosic ethanol, then maybe they would accept that product as biodiesel (which would qualify for the subsidies).


Robert Rapier

He responded, but on the topic of Kergy he wrote "I am not interested in public disclosure of what we are doing at Kergy at this stage. Hope you understand." Of course I wasn't asking for proprietary information; I just wanted to know what distinguished this patent from previous gasification patents.

Again, my purpose here is certainly not to denigrate those involved with Kergy. In fact, I think what they are doing is definitely a step in the right direction. But people should understand that this is not brand new technology, so they shouldn't think that the cellulosic ethanol problem has suddenly been resolved with a breakthrough. Biomass gasification certainly works, but it worked 20 years ago. It is just a capital-intensive process that has the problem of competing against lower cost (but unsustainable) gasification options. And with the news reports of sky-rocketing costs already having an impact on planned GTL projects, it is not clear that BTL will be able to compete for quite some time.

Hello R-squared,

First off:  Congratulations on your promotion and coming relocation to Scotland!  I wish you and your family the very best!

Next, thanks for this keypost [loved the humor of the technical wording for a cast-iron fireplace].  Those of us without extensive technical knowledge can be bamboozled and led astray by becoming confused by engineering arcana.  Perhaps this is exactly what Vinod Khosla is hoping for to suck in investors in his KERGY venture, then quickly bail out by profitably selling his stake.  I found it telling that he refused to answer your specific, non-proprietary request on what made the patent unique.

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

I think Khosla deserves a bit of slack on this one. The question "what distinguishes this patent from previous ones?" must be answered in the patent itself - it is the basis of the novelty requirement of the patent process. Given that RR hasn't thoroughly investigated the patent (he admits as much himself) and none of the rest us probably has the expertise to do so, it seems biased to me to assume that the patent is bogus. It could be bogus, of course, but it is equally possible that Khosla has been deploying a massive corn-ethanol decoy for the past n months, only to divert competing venture capital from the gasification niche. If he does have a genuine cost-reducing technology (like a lower-temperature gasification process) he would do well to not give competitors any hint of the workings of it and let them figure out the patent for themselves.
Given that RR hasn't thoroughly investigated the patent (he admits as much himself) and none of the rest us probably has the expertise to do so, it seems biased to me to assume that the patent is bogus.

I want to make it clear that I don't claim that the patent is bogus. The patent examiner, after looking it over, decided there was enough novelty to grant the patent. All I am trying to point out is that certain reports that liken this to the discovery of fire are way off base. The reason this is important is that some believe that this patent will suddenly turn "cellulosic ethanol" from a uneconomical venture to a profitable one. In truth, this will mean some incremental cost advantage over the capital costs of biomass gasification. That is certainly good, but we shouldn't get carried away with expectations. I won't want us to take our eye off the fact that we are going to have to power down, and this is not the magic solution that saves us.

I really think the reason Khosla didn't answer the question I asked is that he probably wasn't quite sure. That's not a knock on him, because that is not his area of expertise. I don't expect him to know the technical details intimately. I just read the patent twice, am familiar with gasification, and the novelty didn't jump out at me. I read the claims, and found myself asking "why are those novel?"

But that's the way patents work. I have been involved in some like that myself. Joe Blow invents process X, and claims that it works from 800 degrees to 1400 degrees. We come in and do the same process at 700 degrees and file a patent. That's the way most patents go.

Klepper's patents are related to the gasification unit - an expensive piece of equipment but arguably the best gasifier on the market.

Gasification is important if your feedstock is a solid i.e. coal or biomass but not so if your feedstock is already a gas and both production paths require a highly selective EtOH catalyst.

Gasification is important if your feedstock is a solid i.e. coal or biomass but not so if your feedstock is already a gas and both production paths require a highly selective EtOH catalyst.

Yeah, it wasn't at all clear to me what they were doing on the back end, or whether they have figured that piece out. Due to the limited number of people working on syngas to ethanol, I thought maybe they were talking to Syntec about the back half of the process.

Too bad Kergy doesn't have an office in Scotland. We need your talent in renewables, not in discovering yet more CO2 producing oil. But thank you as always for your thoughtful articles and comments!
We need your talent in renewables, not in discovering yet more CO2 producing oil.

It was a tough call, and I will elaborate a bit. If Kergy had moved faster, things might be different. As it was, it took them a while to get in touch after Khosla's inquiry. By the time they did, I had already accepted the other offer.

As a result of my blogging, I have gotten at least 20 job offers or inquiries over the past year or so. Many of them were in California, and many of them were to run or build ethanol plants. In no case was the situation attractive enough to dislodge me from Montana, even for a high 6 figure income. I thanked each person for the inquiry, but told them I am happy where I am. The fact is, I and the family are very happy "where" we are. I would have had a lot more job satisfaction from working on renewables, but we wouldn't have been happy living in Silicon Valley.

The offer from Scotland has aspects the other offers didn't have. First, the location is perfect. We visited Scotland when I lived in Europe before, and decided if we ever had a chance to live there, we would go. Second, they gave me a healthy bump up the food chain to a level that most people in the organization never see. Given that a person can be stuck at my level for 15 years, and I have only been at this level for 2 years, the bump up was huge. Finally, I will be working with a Scot that I worked with a couple of years ago. He is a man with a passion for his job, and his enthusiasm is contagious. I loved working with him. Put all those aspects together and it was a perfect situation.

True, the job is in oil production instead of renewables. But make no mistake, we still need oil production. I believe we need to wean ourselves and get by with less oil. I believe in the reality of Global Warming, and I believe we need to get off of fossil fuels completely ASAP. But we can't do it cold turkey, because there just isn't a replacement ready without accepting a massive population reduction. So, we need time, and I don't think even the staunchest alternative energy advocate would deny that right now we need oil. Those were the factors that weighed into my decision, but it was still hard for me to break the news to Kergy.

As a result of my blogging, I have gotten at least 20 job offers or inquiries over the past year or so. Many of them were in California, and many of them were to run or build ethanol plants.

Here is an example, received just about 15 minutes ago, of the kind of inquiries I see on a weekly basis. I only deleted the name, area, e-mail address, and phone number:

As a fellow chemical engineer and business man, in my search for Bio Butanol technology, I came across you blogg and essays. I am based in [deleted] metro area and would like to talk to regarding any pilot plant work/scale up production plant design and production economics for the Bio Butanol manufacturing that is available under an NDA for evaluation. I am applying for a grant/ loan guarantee for commercialization Bio Butanol.

Please let me know of your interest and what number I can reach you. Thanks.

I have certainly seen some that piqued my interest, but none that were attractive enough to dislodge me until the offer from Scotland.

Further to my comments about the new job, one thing that I will be absolutely passionate about in doing projects is energy efficiency. That has always been important to me, and every unit I have ever been associated with saw an increase in energy efficiency during my tenure. So it is my hope that some of these projects that come online will do so with a higher level of energy efficiency than they otherwise might.

To Robert Rapier,

First, Congrats, and best of luck in Scotland, anyone who can't understand the allure of that place either hasn't thought about it, or is jealous! :-)

On the Bio Butanol work of yours I have read, it certainly got my interest up and I am still studying it like mad!  It has all the right requirements to me, being high up the Hydrogen/Carbon balance ladder, that is to say, mostly hydrogen, and shows signs of being economical to produce, and able to make use of much infrastructure as it exists.

My current leanings run to this....a fuel of the type of your Bio Butanol providing heat for a Stirling cycle engine to be used in CHP (Combined Heat and Power) units, stored onsite like propane...also use as the prime mover fuel in hybrids comes to mind...:-)

I think it wins out for now over Cellulosic Ethanol, and could even be a better alternative in many ways than Bio Diesel for selected markets.

Man, there is a lot of work still left to do in the next decade or two, isn't there?

Don't forget, once your settled in, your promise to get back "on post" with us poor folks!

Roger Conner  known to you as ThatsItImout

On the Bio Butanol work of yours I have read, it certainly got my interest up and I am still studying it like mad!

I probably get more inquiries on this than on any other topic. I would encourage folks to check out:


They have some good information there, and are working to promote bio-butanol.

Don't forget, once your settled in, your promise to get back "on post" with us poor folks!

It's going to be off and on for a while. I will be able to post a lot some days, and other times I will probably disappear for a week or more. Just wanted to let people know, especially if they e-mail and I don't answer.

As a result of my blogging, I have gotten at least 20 job offers or inquiries over the past year or so.

Is this what happened to Stuart as well?  Or did he get tired of the topic?

I have never heard a completely straight answer on this either. I think he is just pursuing some consulting, but he may have also gotten tired of the subject.
Hi Robert,

Thanks for your clarifications. About working with someone you respect and who is passionate, I agree, that can make all the difference in the world.

Maybe you'll consider getting back into renewables once you've made your fortune? Maybe Kergy will let you telecommute? (from Scotland!). We can only hope. Best wishes.

It never hurts to praise your new boss on a public website, as I'm sure you know there is a a good chance that he'll see it and be pleased. It's so important to get off to a good start with a new position.  

You appear to be perfectly suited for a fine career in the Big Oil corporate world, but don't expect all of us to automatically swallow your claim to objectivity and impartiality.

I do believe you are sincerely interested in energy conservation, but would you be willing to state here out in the open that you work for such-and-such oil company and that you'd like all of us to use less of your company's product?

Corporate people, particularly engineers, generally have a hard time realizing the inherent conflict in publically commenting on issues that affect the company that provides their living.   I know - because I've been there myself, in the environmental rather than the energy field. I will state flat out that if a company is paying your salary, you cannot in good conscious publically say anything negative about said company (if you want to keep your job). There is a lot to be critical about the oil industry, but you are hardly in a position to say it, even if it needs saying. You have to leave that to someone else to say. Which is OK.

Having said that, I sincerely believe you are a major asset to TOD and hope you will not fade away due to the demands of your new position.

It never hurts to praise your new boss on a public website, as I'm sure you know there is a a good chance that he'll see it and be pleased. It's so important to get off to a good start with a new position.

LOL! You have no idea how far off base you are. I am well aware of my faults, but one of them is not doling out false praise or sucking up to the boss. I speak my mind, and if I give a compliment people know it is sincere. At my former company, our VP of Technology once had a discussion with me, and he said I could be in his position some day, but I have to learn to play politics a bit more. He told me I am too straight-forward with my opinions, and that this isn't always the best approach. I told him I detest politics, and I believe in saying what's on my mind. He smiled and said "Well, you will never be a VP."

Furthermore, check the domains sometime via the Sitemeter to see if any oil company domains show up. I haven't even looked, but I bet visits are extremely rare. Within my company, do you know how many times I have heard the topic of Peak Oil come up? Only when I have brought it up. It is akin to talking about UFOs. So the odds that my future boss (who is not even the guy I was referring to; the person I referred to is a friend, not my future boss) is visiting TOD are pretty slim. You have better odds of being struck by lightning today.

You appear to be perfectly suited for a fine career in the Big Oil corporate world, but don't expect all of us to automatically swallow your claim to objectivity and impartiality.

To be honest, it is not of great significance to me what you swallow or don't swallow. It is not possible to please everyone. Some on here know me personally. They know what I am about. That's good enough for me.

I do believe you are sincerely interested in energy conservation, but would you be willing to state here out in the open that you work for such-and-such oil company and that you'd like all of us to use less of your company's product?

I want you to use less oil. Period. But I don't want you to stop using my company's product if you are just going to use XOM's product instead.

Corporate people, particularly engineers, generally have a hard time realizing the inherent conflict in publically commenting on issues that affect the company that provides their living.

I don't talk about company-sensitive issues, and I don't criticize my company in public. There are things that I would rather not see us involved in, but those issues are communicated and discussed internally. Now, I have no problem criticizing XOM or Shell, but I won't criticize them for doing something my own company is doing. I have also never said in this forum who I actually work for, although many do know. My testimony at the Montana legislature - which identified both me and my employer - is in the public record, and a lot of people figured this out a long time ago. It's not that I have any problem with people knowing who I work for, as long as they understand that my views in no way should be assumed to reflect the views of my company. Sometimes they probably do (on grain ethanol) and other times they certainly do not (on gas taxes).

Now, I only explain myself about once a day, and that's my quota for the day. Actually, to be honest I did it another time by e-mail today, so I will skip doing it tomorrow.

Welcome to Scotland.  Hope everything goes well for you.

I'm Scottish but currently living in England.  I'll probably return someday.

Thouroughly enjoying your commentary on the ethanol bondoogle by the way, keep up the good work.


There is a huge syngas facility in the US, built back in the early 80's just as oil prices peaked. It is in Beulah ND. It uses lignite coal (sometimes known as brown coal) to produce "natural" gas, plus an array of by-products such as CO2.

Check it out...


There are also some large coal gasification plants in Germany. I used to work at one of the facilities. But they are very dirty (soot everywhere) and very capital intensive. However, I think we will ultimately use our coal, as much as I wish we would leave it in the ground.
Robert - many many thanks for this article.  I have been waiting for it so that I can leave TOD alone for awhile (burn-out).
Your chart would point to coal gasification as the least costly option.  With the powers that be my guess that this will be our future, the enviroment be damned.

I think all of us non-energy tech people have been very fortunate for all the work you, westexas, kebab,+ many other have shared with us.

Congrats on the promotion.  Thanks again!

Coal gasification is cheaper than biomass gasification, but more expensive than GTL. CTL will start to really come on strong as natural gas and oil both head down the other side of the depletion curve. And if you think we have seen much Global Warming already, just wait for what's in front of us.
Yesterday's National Public Radio blurb was that we are 1 degree C from broad melting of the north american permafrost, and release of 100x the global warming gases produced (directly) by man.

It will be sad if that happens, but it will also mean fewer worries about coal.  We will be exploring the upper limits of our earth's global warming potential, regardless.

GW trumps all.  
While a farmer can convert his/her products into alcohol, most stills will require high capitolization and energy cost VS taking the crop waste, drying said waste, placing it in a large metal container (to act as gassifyer) then making gas+biochar.

The last time gassifyers were widespread was the 1940's   So its not like it requires a high level of technology.


The farmer can take  gas output as a stirling or ICE engine fuel, hook it  to a generator and make electrical power.   Or use the gas for heating.  

And unlike the idea of burning everything and making zinc/carbon batteries, placing the previous above ground carbon into the ground and making terra preta.  With some terra preta soil showing carbon 'locked up' in the grounmd for 100's of years and seeming 'self regenerating'

http://forums.hypography.com/101429-post19.html   (start of thread over there)

A soil improving angle is an additional motivation for the farmer to take such steps.  Killing off nasty virus/bacteria/prions by burning is another benefit.

And I just re-found these ppl.
My jaw just dropped.  If this is for real, this may be the first hopeful thing this old hard-bitten doomer has seen in years.

The only thing keeping me from dancing in the aisles is the memory of my similar reaction to discovering algal biodiesel, and my disappointment when the devil stepped out of the details to say hello.

If this is for real, this may be the first hopeful thing this old hard-bitten doomer has seen in years.

Don't worry.   Food will still be more expensive and transportation will become more expensive, while the cheap xport will still be slow.   You'll get your doom on with other people's shoot-em-up reaction to the new reality.


Let me help your jaw out....

Notice how you can take 'normal' charcoal and put it in a bath for a few mins to obtain a nice slow release N for the plants.

I think my head's going to explode.  How come we're not crawling all over this like ants at a picnic?  This looks so right in so many ways, and do-able, too.  Imagine being able to sequester 150 tonnes of carbon per hectare, double the the soil productivity and produce carbon-negative biofuels into the bargain.

Gosh golly gee whiz, where do I sign?

Gilder... where have you been?

As posted on Aug15:

At Sytnec, our scientists have focused on a BTL/GTL process that capitalizes on the thermo-chemical conversion of syngas -derived from any carbonaceous material- to ethanol/methanol and higher order alcohols such as butanol.

The beauty of the Syntec process is that it has been specifically designed to operate in a low-pressure, low-temperature environment (similar to methanol production) using a true ethanol catalyst - not a modified FT variant.

The by-product of the Syntec process (BTL) is char and it turns out that char might be one of the best soil conditioners we could ever utilize in a process called Terra Preta.  I have opened discussions with Cornell Univ. to investigate further potential of Terra Preta as it relates to our work.


What got my attention with this idea were the additional elements of carbon sequestration and soil fertility enhancement.  In one neat conceptual package it addresses three of the greatest components of the problematique - atmospheric CO2, soil depletion and fuel shortages.  As technically interesting as a one-legged solution may be, a broad-spectrum approach like this has a holistic elegance that is very attractive.  The fact that it revolves around charcoal, one of man's earliest inventions, makes it irresisitable.
Gosh golly gee whiz, where do I sign?

You sign in the same place I do.

You talk to the local CSA (Community sponsored Ag) growers.   You build your own wood gas unit.  You build you own wood gas stove  http://www.woodgas.com/bookSTOVE.htm   (I'm using the paint can + #10 can design along with having small fans to help the stove out.)

In an ideal world you'd make something like this

And you start adding bio char to your land.

I thought it was fairly common knowledge that
the new growth following a serious forest fire
was always more vigorous than new growth on
lands that were clearcut by man.

Likewise, most people with a woodstove will
tell you that the garden grows better when
you bury your ashes in the humus.  Also lowers
the acidity...

The effect you are seeing there is the phosperous (and other elements) are far more soulable than tied up in the matrix of bio-char.

The resulting ash doens't hold NH4NO3 well.   Whereas the biochar can be soaked in NH4NO3 and that char will slowly release N to the plants.

So I went to the first website and come away with questions which I can find no answers to on that site.

Here is some:

  1. It looks like a boy scout thingy. So where does the smoke come out at?

  2. Can I use it indoors?

  3. I can't see placing a heavy cast iron skillet or pot on the flimsy looking top of it. How does that work?

  4. If inside would it not be dangerous?

  5. If I wanted the properties of heat then how does that work? Is the heat just radiant or convection or heat waves? What?

  6. The pix looks cute but frankly looks very flimsy.
I wonder about it tipping over and what happens.

7. How much fuel does it hold.

In the above I am referring to Toms device. for $55 or so.

In other words can it hold up to the stress of daily use and for heating how long will one load of fuel last? With a smallish looking cylinder it seems limited.

Am I asking the wrong questions and why doesn't that website show one in use or answer these with a FAQ?

Lots of questions and I am not being negative but I have spent good money in the past on what turned out later to just be junk. The price is cheap but that doesn't mean much. I would prefer to spend more and get something substantial.

Currenly I am looking at a Quadrafire which goes for about $2,000.00 plus. I have had for many years my Buck Stove but its not worth a damn to cook on don't know.

I could find an old farm woodfired cookstove and be happier but...well they are getting very rare of late.

So I went to the first website and come away with questions which I can find no answers to on that site.

Then e-mail them.   Or, spend some time researching the topic of stoves that use wood chips as fuel.  And how they work.

Because you really DO know the answers to your questions.  

Like this one

I wonder about it tipping over and what happens.

What do you THINK is going to happen?

Quadrafire.... Buck Stove

And these stoves make bio-char (and can be stopped at the point of making bio-char) as part of their heating process?

And I'm sure in your survial-forage mode after the crash, you'll be lugging about that quadfire.

Well Eric since you posted the topic I figured you might have the answers to some of the questions that immediately sprang to mind.

I was also looking for personal evaluations of the product.

Drawbacks I see,(nothing personal intended so chill out a bit)

  1. Must be reloaded and I assume new fire built each time the previous load is burnt/charred/whatever.

  2. Good for perhaps an hour. In other words won't last overnig ht.

  3. Good for cooking but maybe not so good for serious heating.Like a tent would be ok but 200 sq. ft. of a small hut/cabin would not work too well.

  4. The variability of the fuel. Have to do a lot of woodsplitting to get it sized down whereas a normal stove can take larger (far larger) sizes. Sometimes just cut rounds like 2'x6"...and can be dampered down to burn all night or while your away for an extended time.

I wander(without going to googleland exploring) if they have sized these up to work in a large enviroment. Guess I need to answer that myself then.

PS. Tipping over. With kerosene heaters (like a lot of us used to use) you can have a very big problem but there were builtin shutoffs. Kerosene heaters smelled badly. They burned the oxygen out and were therefore a possible hazard.

A supply of wood is no problem for me. I have plenty and just the deadfall is sometimes enough. Toting it home with no tractor..thats a problem. Running a chainsaw would be a problem since no fuel.

The real problem I see it is if there were a large population(a soft landing scenario) using it, then how long would our forests last? How would you manage to obtain larger quantities with no petrofueled vehicles to deliver or pick it up with?

One would I suppose have to scavenge and that might be problemmatic. Fights over woodchips and assorted incidents.
Rural folks would be ok but ahhh those city folk.

I did think of one solution.
In Kentucky wild cane is making a big comeback. In the distant past Ky had huge areas of canebrakes. There are many groves of it growing all around my area currently.

It grows very prolific and is very similiar to bamboo. We use it to make canepoles for fishing. It is actually considered a pest weed by farmers but lately they have not been spraying it.

Indians used to hide in it when raiding so it achieved  a bad name IIRC. It grows very very dense. Myself I like it and planted some in my backyard out beyond the woodpile.

This would be rather easy to harvest and carry distancewise and seems to be just right for the size desired as fuel.

One of the reasons for early woodsmen coming to Ky was looking for those elusive canebrakes. Simon Kenton. They thought they were of the sugarcane variety and spent a lot of time trying to find them. They finally did and realized it wasn't going to work out. By that time D. Boone had made his trek to find ground for 'Transylvania'. Kentucky had far more going for it than a variety of cane.

Two(maybe three) of my kinfolk fought and lived  with D. Boone at Boone's fort just south of Lexington.

Make a weight carrying frame to hold heavy pots on the stove and prevent tipping. I've done this for a kerosene stove running on biodiesel. I might get one of these gasifier stoves as my Christmas present to myself. The AA batteries to run the airblower can be solar recharge nicads.
And before you buy this gift to yourself - you can go read the manual here.


I've got one.  They're small, one load of fuel goes relatively quickly, but it will heat water fast.  They work best with a dense, uniform fuel source, like sawdust pellets or just relatively uniformly chopped sticks.  The premise is that the pyrolizing mass sits at the bottom and the gas is sucked through the bottom holes, up the sidewalls and burned at the top. It can work smokelessly for periods of time, but if the reaction is disturbed, it will smoke.

It's going to be replacing my 22-year-old Peak1 white gas backpacking stove, which is something I freqently depend on, so I don't think of it as a toy.  There's an art to using it properly, though, not unlike the art of building a good campfire.  I have a feeling that I'll be much better at using it a year from now.

If I were to try to use it for household applications, I'd be disappointed.  But if I had to build a larger system, it'd be invaluable as a working half-scale model.   I certainly consider it to be worth the fifty-five bucks.

Does it use one fan or 2?   Any speed control on the fan(s)?  And if it uses only one fan, how do they control the air flow at the top to simulate a tall chimney?
One fan, two speeds 'High' and 'Low' -- I'm not sure about your third question.  You can restrict airflow from the bottom holes by closing them off with screws, but I don't think that's what you're asking.  The theory seems to be to pull the pyrolized gas away from the fuel before it can ignite and igniting that gas at the top of the stove, closest to the object you're trying to heat.
ooh ooh.

I'm thinking that this low-tech burner has great possibilities in the Third World.

Bearing in mind that poor soil fertility is an absolute brake on development for hundreds of millions of people. And that they, by definition, can't afford to pay for any sort of fertilizers or amendments. Run your biomass through your cooking stove and improve your soil in the process...

The critical question is having enough biomass initially, before the positive feedback loop kicks in (improved soil produces more biomass). The temptation being to use or sell the charcoal as... cooking fuel.

And here is a bit more...

How was Terra Preta formed?

The story behind Terra Preta is only now beginning to unfold. As well as the characteristic high fertility of these soils, another identifying trait is the high presence of ceramics, charcoal and highly aromatic humic substances. This combination of evidence has lead researchers to believe that these soils are of anthropogenic origin and carbon dating has shown them to date back to between 1780 and 2260 years.

Eric I could kiss you!  Pictures are a thousand words my friend.  Great Post.
The kisses are due your way when your process devices are cheap enough for a farmer to process his/her own bio-mass into bio-char and do such without TOO much effort.   (because farmers don't need more work)

Otherwise, its cobbling time (and I make my own stoves/wood gas generator/storage rigs to make gas to run a lawn mower ICE hooked up to an alternator)

if it sounds too good to be true...
Do you have a point to make?
yes don't go jumping around saying we're saved at half baked ideas like this.
half baked ideas

Go ahead.   Show how putting BioChar in the soil doesn't result in the carbon being unused for years.

Show how adding bio char to the soil doesn't result in better plant growth

You are the one claiming halt-baked.   Now feel free to show WHY it is 1/2 baked.

If man is willing to 'take CO2 from smokestacks, feed that gas to algae in tubes, then burn the algae-oil' and call it "solving the atmospheric CO2 problem" then by all means show how the idea of burying bio-char is 1/2 baked.

hahaha. I think you got baited into that one. At least you can claim that.

No. YOU need to show WHY.
And it's "half." Halting is what you should think about. But you already were. Good.

You may be on a one-man misson to save the world, but it looks like you're gonna need some help. Look around. Who do you think are gonna be your options? The bitchy position isn't really working for you.

No. YOU need to show WHY.

The claim was 'half-baked'

   2. Informal. Insufficiently thought out; ill-conceived: a half-baked scheme.

   3. Informal. Exhibiting a lack of good judgment or common sense: a half-baked visionary.

I've asked why the idea of putting bio-char is 'lacking good judgement' and have put forth how the Biochar Carbon has the staying power of 100's of years AND how plants do grow better in soil with biochar.

Perhaps TrueKieser has actual data that shows how biochar is a flawed idea.   Rather than just handwaving.

And it's "half."

Quick!  Lets gather about the warmth of the spelling flame!
My, the heat of that flame should be able to power humanity for years!!!

You may be on a one-man misson to save the world,

Ha!   I'm only interested in saving myself.   The gravity of The World is all that keeps me down.  

Who do you think are gonna be your options?

Not you.  Too oily for my tastes.   Not to mention you are WAY over there and I'm WAY over here, thus out of range with all the localization.

Don't try to fuck with me, dude. I watched you try to take on Kevembuannga. I had already wasted him before you showed up. Now you are starting to sound like him.

I will mess you up just the same. My advice to you is to start talking about oil. Real serious. Real fast.

Don't try to fuck with me, dude. I watched you try to take on Kevembuannga. I had already wasted him before you showed up. Now you are starting to sound like him.

Threats.  'spose that is a step up from spelling/grammar flames.   Perhaps one day you'll graduate to actually discussing a point.   Or admission that you were wrong instead of making threats.

If you 'wasted' someone, how could anyone else show up later?  See, this world you've created where you are 'wasting' people and 'getting fcked with' is all in your head.  

I will mess you up just the same.

How?  With your wit?  Or by providing heat with spelling flames?

The only messing-up is going on in your head.

My advice to you is to start talking about oil. Real serious. Real fast.

Lead by example oh blatherer about Paris Hilton.  

Biomass gassification != oil.   Please feel free to tell Mr. Rapier that he too needs to "start talking about oil. Real serious. Real fast."

Eric. Please keep posting. Seriously.
You are absolutely correct on most of your points. To be honest I was expecting to come back today and have to make several apologies and maybe even excuse myself from further service to an ideal. Your aggressive counterattack and tone negated that scenario. At least for the time being.

I'll be making quick work of you soon. And Paris is rather offended. She feels you didn't need to drag her into it. I kindof agree. I shall have to defend her honor.

Too bad you can't use the spelling/grammar thing anymore. Damn you're slow! Better bone up on the numbers. I really don't see anything else keeping you from the slaughter. But I've been wrong before.

Start reading your bible and learn to swim.

(which point did you want to discuss? hopefully it's about oil, that's all I'm good at)

(which point did you want to discuss? hopefully it's about oil, that's all I'm good at)

And yet your reply had nothing to do with oil OR the topic at hand - taking plant matter and making alcohol or various gases.

But here is another link for anyone still reading:

And this is the link to the 2 fan stove plan.

"The "Turbo" is a wood-gas, adjustable heat, cooking stove that burns small pieces of wood or other biomass fuels such as nut shells, corn cobs, etc. An extremely clean burning stove that can be used indoors with only minimal ventilation and cooks as fast as a modern gas or electric stove. It can boil 500 ml of water in 3.5 minutes, comparable to an electric or gas stove. It uses a 3 Watt blower and develops 3 kilowatts of heat.......It burned for half an hour, and left us with a pile of nice charcoal sticks."

So to cook with biomass gasification and leave you some biochar is doable on a low tech/low budget option.

Awww... did somebody's brain not quite register that the topic of thread is Cellulosic Ethanol vs. Biomass Gasification?

Poor schmuck.

Feel free provide us with Eric's 'saving the world' quote.
Congrats, anyone I know who visited Scotland said it was beautiful so enjoy.  How do these processes compare to something that made the publicity circuit known first as "Thermal Depolymerization" then as "Thermal Conversion?"  And if anyone knows, how does one go about making a claim to some oil shale bearing land?
Does anyone have suggestions on the species of willows used for bio-cropping?
I grow basketry willows for coppice fuel...what is your climate like?  I am passingly familiar with several Salix species.

All willows are fast-growing, but some are more fast-growing than others.

I have a question about biomass gasification.

The biomass is being gasified in an anaerobic atmosphere.  I as understand it usually pure oxygen is fed into the gasifier but obviously in less quantity than required for full combustion.  As a result you get syngas (ie, CO & H2)

So where does the pure oxygen come from.

As I see it, you can either cryo liquefy regular air and fractionate the oxygen off, or you can run it through a pressure swing system.

Both of those processes are going to consume prodigious amounts of (electrical?) power.

Does anyone (Robert?) have any data on power requirements per tonne of biomass gasified?

So where does the pure oxygen come from.

As I see it, you can either cryo liquefy regular air and fractionate the oxygen off, or you can run it through a pressure swing system.

It comes from an air separation unit (ASU). That is a big chunk of capital. Kergy says they are gasifying in the abscence of oxygen, and thus don't require an ASU. This would be a big capital savings. On the other hand, if they aren't adding oxygen, then the reaction is not going to be self-sustaining. That probably means continual inputs of energy into the process. There is just no free lunch.

I will have to look you up when I am over there. We can go to the pub and rail against those "bloody Brits." :-)

Gaseous oxygen can be produced for ~ 10KW/1000 scfh for cryogenic units, slightly less for PSA.  There would be additional for O2 compression.
Could someone point to a serious analysis of the amount of land required to capture solar energy using various plants, and the amount of energy extractable / acre with various processes?

My instincts tell me that running anything like the current car based economy on biomass is going to decimate the land and compete with food production.

I've heard figures like 11 acres of land /car / 15,000 mile year.

I've heard figures that suggest you can run a car on the biomass from just an acre of land (maybe that was a cellulosic ethanol claim?)

But whether you need an acre or 10, a significant proportion of the ag land of America would be required by a biomass economy.

If so (if!) why are we even talking about going down this road?  

I'd really appreciate a pointer to a seriouus analysis of energy/acre, and a comparison of that with current levels of energy use in cars.  

It is my understanding that plants have photosynthetic efficiencies of less than 1% from sunlight to biomass. This means that even if ALL of the energy in biomass vould be converted into useful energy, one acre of solar cells at 15% can produce as much energy as 15 acres of agricultural area. In reality things are much worse, though, because solar cells produce electricity and the efficiency for thermodynamic engines is around 40%. This means that we need 37.5 acres to produce the same amount of electricity that we can get from solar cells. If we assume that biomass processing is only 50% efficient itself, we now have a ratio of 75 acres of agricultural land for every acre of solar cells.

It seems to me that if we paid our farmers the investment to put solar cells on the roofs of their barns, we would get more net energy out of our land than with the best biomass infrastructure we will ever be able to build.

That, of course, is a line of action that will never gain any political support because there is no industry lobby to electrify barn roofs but plenty of lobby to build biomass processing plants.

In other words: politics and simple physics are not always compatible. And since physics couldn't care less, the loosers will always be those who elect the politicians who don't care about physics.

In response to this I'll weigh in.

I've heard that fast growing willow coppice, can yeild approx 10 tonnes dried wood per hectare, per year.  In operation the coppice is clear felled every 4 years producing 40tons/hectare.
Sorry, I don't actually have a link for this, but intuition tells me this is accurate.  Certainly there are a few power stations being constructed in the UK which are planning to use fast growing willow so it must be viable.

Now, one of the Syn gas companies has a biomass to liquids process that actually (in prototype operation) yeilds 1 liter of ethanol for 2.3 kg of dry wood.

that equates to 4,347 litres/year/hectare.
Now ethanol is equivelant of 1.6litres ethanol = 1 liter gasoline.

So the energy output is equal to 2,717 liters gas/year/hectare.

Thats enough fuel for a 30mpg car to travel 21,500miles.

Or enough for 2 average year motorists.

So on that average 1 hectare provides enough fuel for 2 cars.

So 2 cars/hectare.  On this basis, I believe that for agricultural type operations (pick up trucks etc) this is entirely viable and sustainable.

For whole cities worth of cars its a different story.

Hope this helps.

Thanks for all of these responses.

If it is true that we have 953 acres of ag land in the US

and only 60 or 70 million cars

and 1 hectare can fuel 2 cars for a year.

and 1 hectare is about 2.5 acres

then 2.5 acres can fuel 2 cars for a year

and 1.25 acres can fuel 1 car for a year

So with about a 10th of available ag land acres we could run a moderately efficient car fleet of current size.

Well that's actually quite doable... more than I would have guessed.... although topsoil and water issues would be exacerbated.


That's still not really all that great, to be honest.  We're talking about more than an acre of land to run a car for a year.  A solar array that can fit on the roof of a medium sized house can easily power a small, efficient electric car for 15,000 miles per year.  If we go with the most efficient cars possible (rather than the average) maybe we could get the agricultural area down to 3/4 of an acre, or even half an acre.  That's still much, much worse than just using PV to charge an EV.  

Assuming we can roll out PV and other green sources of energy (wind, hydro, etc) and nuclear energy, I really think most of these synthetic fuels from biomass are not going to prove to be that useful.  For that matter, do they even make sense from the standpoint of converting coal?  I mean, why bother converting coal to liquid fuel, when you could just as easily burn coal and use it to charge EVs?  

You may be right, I think that solar PV will be the main technology which saves us in the long run. But for now, I perceive that biofuels may have some things in their favor.

You would need to cover more than barns, you would need to cover acres of land with PV panels. It seems to me that right now it would be much less expensive to plant them with a good energy crop. True, you would need the expensive BTL plants that I just learned about, so I don't know offhand how the economics works out between these two options, but suspect it wouldn't be in favor of PV.

If you need liquid fuels, then BTL does this directly. True, electricity can produce hydrogen, and that plus CO2 should produce methanol. But which is more efficient? For the near future, I suspect biofuels are.

Electricity from PV (and wind) certainly wins out vs. electricity generation from biomass as you indicate. But even here, the biomass generation would at least not suffer from intermittancy.

It seems to me that biofuels have a role to play until we figure out and construct the best PV infrastructure.

Sunman said,
"You would need to cover more than barns, you would need to cover acres of land with PV panels."

It always amazes me that when people think of solar panals, especially in large quantity, they want to try visualize putting them down on the ground, on land that would be perfect for agriculture.  Why?  Let's try to use the acres we already have that can't/won't be used for anything else:
Roof tops of houses, stores, malls, factories, office parks, Super Walmart's...how many acres are we talking about nationwide right there?

The most over looked place to put alternative energy projects are the so called "brownbelts" around every industrial, or better to say, formerly industrial city.  For a country boy like me, my first drive to Chicago was absolutely eye opening....when I got to Gary Indiana....miles and miles of abandoned crapped out clapped out buildings, abandoned railyards, abandoned warehouses, abandoned steel mills, abandoned lakefront industrial property and docks, it was one of the most incredible wastes of thousands upon thousands of acres, and right next to one of the largest population centers and energy markets in the nation!  You could have put 50 giant windmills out there and no one would have ever noticed them, mixed into abandoned cranes, electric power high voltage towers etc.  And then I read an article only a few  days later whining about where to put windmills, where they would not "impede views" or interfere with local life due to their noise or interference with property development!  IDIOTS.
Every major city in the U.S., and most minor ones are cursed/blessed with miles of "brownbelt space".  USE IT.

Roger Conner  known to you as ThatsItImout

It wasn't my intention to suggest that farmland should be used. I can't but agree with you: solar panels do not require farmland. Quite the contrary.

You are absolutely right with your argument. And since the efficiency of silicon is so much higher than that of photosynthesis, using farmland that we need to produce food is a waste and a crime in a starving world.

Driving through the urban Southwest of the US, one will indeed notice hundreds of square miles of flat roof areas burning in the sun. Every sqare meter of these roofs can produce 20W of continuous electricity (120W peak) at current efficiency levels. That is a lot of energy being wasted. Actually, most houses in CA could be made completely energy independent with solar heating and photovoltaics. Malls and their parking lots offer unused areas that could generate on the order of GWs of peak power in summer, covering all of the AC peak demand.

With electric cars and plug-in hybrids becoming mainstream one can show that the parking lot areas, when equipped with solar panels, provide enough solar electricity for the average commuter. Those solar panels will cost approx. 20-30% of the cost of the car. I believe the average driver spends a lot more than that on gasoline over the car's lifetime right now.

Roger, thanks for your observation about using brownfields for solar PV. I hadn't considered that before, and it makes a lot of sense. I am encouraged by the idea of "biofuels plus PV" instead of "biofuels or PV".

I know from some of your comments that you consider the energy problem to be mainly a "liquid energy problem". If so, then it is important to find the best way to convert electricity to liquids. Have you considered the approach advocated by George Olah in his book "The Methanol Economy"? That is, make hydrogen, react with CO2 from fixed generation sources, and get methanol, which could be the starting point for a lot of additional synthesis. Do you have an opinion on this?

In that way, we could avoid the rather significant problems associated with using hydrogen directly.

Tony Verbalis

"I know from some of your comments that you consider the energy problem to be mainly a "liquid energy problem"."

Yes, very much so.  But I think that stationary utility energy is absolutely connected and the "web" of energy use and production needs to be altered across the board.  For example, a bit of renewable stationary power (wind, solar) and conservation (ground coupled heat pumps, passive solar, solar hot water, and well insulated and bermed housing and business buildings) could free up massive amounts of natural gas, propane, and electric power which could be used for transportation.

This is not "high tech", but high efficiency and artistic efficiency design.

With the freeing up of natural gas and propane through alternatives/efficiency, CHP  (combined heat and power) using them as the prime fuels become much more economically viable, and makes distributed power generation a rapidly growing part of the mix, including renewables.
 Now to George Olah's "Methanol Economy".  I think methanol will be a part of the mix, as will propane (one of the most under talked about potential transportation fuels) natural gas, butanol and bio butanol, and yes, hydrogen.

Despite what many seem to think, and they are certainly entitled to their own views on this, and my view is surely in the minority here on TOD, I think the "hydrogen" option is being greatly underrated here, and that it will be bigger than many folks think, and sooner than many folks think.  I do not believe it is the "silver bullet" single cure, and do not believe that renewable hydrogen alone can carry the energy needs of the economy.  But I do think that distriubuted onsite production of hydrogen, in particular in industry and transport facilities, can assure that the "critical need" transport issues can be greatly assisted by renewable (wind and solar) hydrogen production, combined with methane production from agricultural waste, sewer gas and landfill gas, and you are talking about being able to provide critical train and highway trucking, and aircraft fuel.  In other words, the fantasy that every last truck, train and car is going to grind to a halt, and people will be dragging carts behind them up and down the interstate, or using donkey carts is just that, a pure fantasy.  

As to the exact method described 'make hydrogen, react with CO2 from fixed generation sources, and get methanol, which could be the starting point for a lot of additional synthesis. Do you have an opinion on this?"

It all depends on the cost per BTU, I surely have nothing against it, but let me repeat something I have said here before, and gotten pretty well chewed and spit out for saying:  I think the "rather significant problems" of "straight hydrogen" have been greatly over exaggerated.  Methane and natural gas are not far removed from hydrogen, and we use them, and tolerate having to contend with and dispose of methane in mining, sewers and landfills.
People die in natural gas explosions every year in this country.  I know a man who was almost horribly killed, and was burned horrifically by a propane bottle explosion and fire.  People speak of "metal embrittlement" by hydrogen as though it were a barrier greater than attempting time travel.

It is amusing that once a chemical or process gets the reputation of being "difficult", in only a few years, it begins to take on almost magical properties.

Say "radiation" and peoples ears stand up.  Say "hydrogen" and people smile and grin, as though you are talking cold fusion in a mason jar.  Let me tell you a little secret....the human race has burned nothing but hydrogen in it's whole history!  The carbon in hydrocarbon fuel is an annoyance, a pollutant...but it does one useful job...stabilize the hydrogen, until it is released.  The goal of combustible fuel should continue to be, move up the hydrogen/carbon ladder, until at some point, you arrive at the "hydrogen" alone top rung.  The question many of us are starting to ask is why not skip the pollution, carbon release, cost, wasted resources, and wasted time of  the middle rungs and go to the top rung as soon as possible.

I was one of those who used to smile or even laugh at "the hydrogen economy"...that is, until I started seeing some of the alternatives.
It makes hydrogen look absolutely efficient if you compare it to the filth, the waste, the carbon, the complicated "ten thousand conversions" of ethanol, tar sand, oil shale, etc.  The shortest distance between two points is still a straight line.  We all admit that all of the fossil fuels that are NOT renewable are only stopgaps anyway, chasing the depletion curve, first, light sweet oil, then heavier oil, then natural gas, then coal, then tar sand, then oil shale, then....in the meantime, the carbon release, the torn up ground, the depleted water, the sheer filth of the whole operation will have been staggering, not to mention the steel needed, the copper needed, the refinery capacity needed, the transport system needed to move the raw material and then the finished product about...very few species can survive another two centuries of that kind of mining and fossil fuel onslaught...possilby not even the human one.

It would be the grandest "incidental" terra-forming" operation ever imagined, but right here on our home planet, the only one we know of that is already terra formed for life, millions of varieties of it.

Are we sure, based on a simple minded efficiency comparison, that leaves MOST costs off the books, that these complicated, expensive, potentially catastrophic "ten thousand conversions" actually stack up better than a more direct path to hydrogen.

I am not.

Clean, NON-CARBON, distributed onsite renewable production of a fuel that can be used for an almost infinite variety of processes.  It will of course be done, because IT HAS TO BE DONE.

Roger Conner  known to you as ThatsItImout

"It makes hydrogen look absolutely efficient if you compare it to the filth, the waste, the carbon, the complicated "ten thousand conversions" of ethanol, tar sand, oil shale, etc."

I certainly agree with you here, especially the tar sands and the oil shale. Your reply was eloquent I thank you for it. Plus, I also think we will need the high energy density of liquid fuels for quite some time.

Hydrogen will have a role to play, but I just see too many problems with storage and handling. It is not a true liquid. I have calculated that the reaction between H2 and CO2 should preserve 90 % of the energy of hydrogen, and methanol is a true liquid and easily handled.

I don't know how costly this synthesis would be, and I don't think it would be particularly amenable to on-site production. It is also a possibility to use methanol directly in fuel cells.

One big advantage methanol would have is that it wouldn't require a massive change in the energy delivering infrastructure. I appreciate your views and ideas. Using methanol is almost like using H2 directly.

Tony Verbalis


Don't forget that in addition to current industrial "waste lands", as well as comercial ones, there are also many areas that are prime for solar energy, where food crops cannot be easily grown.  The deserts of the Southwest region, for example.  Not to mention in addition to PV there's also reflective dish solar (I don't think this is the real name, but I can't remember it off the top of my head), which uses mirrors to focus sunlight on pipes filled with oil in order to produce energy through heat.  This is supposed to be more efficient than current PV solar.  

So, between PV on rooftops, reflective solar plants and wind farms (along with hydro which we already have) we have a lot of potential tricks in the bag.  The only thing is we need to move beyond our obsession with liquid fuels.  Maybe biomass will prove worthwhile to create synthetic fuels, but we should not assume that is the way to go before examining all of the alternatives.  

I am not denying that biomass has an important role to play. But what I am saying is that solar energy, when measured by its obvious advantages over any other renewable technology is completely underfunded. We could derive several percent of our primary energy from solar if politics hadn't dropped the ball years ago.

This is water down the bridge, of course. Solar energy has become one of the fastest growing technologies and, simply by means of physics, it will overtake all other energy sources over the course of the next thirty to fourty years.

The intermittancy argument is very valid. Solar energy, if it wants to grow beyond approx. 10-15% will need some sort of energy storage. I imagine that we will see a number of different technologies emerge to cover different storage time scales for different applications: thermal storage, flywheels, hydrogen, batteries and even hydroelectric storage will play major roles. I am sure there will be more.  But these technologies have another two decades to mature before we can build up enough solar capacity to actually need them.

And one has to keep in mind that part of the inefficiency of biomass can be mitigated if other renewable energy sources are available to support some of the processing steps. There is no doubt in my mind that a combination of solar generated steam/hydrogen in combination with biomass can be made into a process with reasonable EROI for transportation fuels. It might require some rethinking of transportation systems, though. It certainly makes no sense to transport cellulose on diesel trucks. But it might make sense to use freight trains.

"While natural gas is easier to handle, and coal is cheaper, biomass is the only option capable of producing sustainable energy and mitigating greenhouse gas emissions."

Could a statement be more wrong? Wind and solar energy can produce copious amounts of energy with very low CO2 footprints.

But if one has a particular interest in one topic, it is easy to forget that there are alternatives that suffer from none of the problems of ones own field.

So while the article is informative, I take it for what it is:  a specialists critique of his own field.  

Could a statement be more wrong? Wind and solar energy can produce copious amounts of energy with very low CO2 footprints.

If something is unclear, sometimes it is better to ask for clarification rather than jumping to conclusions. I am specifically referring to the 3 options I metioned: GTL, CTL, BTL. Of those, BTL is the only one that is sustainable.

If you had seen many of my posts, you would know that solar and wind occupy the number 1 and number 2 spots of my most favored alternative energy options. In fact, I mentioned just yesterday that solar is my favorite. I would like to see a solar panel on every house, and I would like to see us driving PHEVs.

So while the article is informative, I take it for what it is:  a specialists critique of his own field.

Because you misinterpreted a single sentence. This essay was about cellulosic ethanol and biomass gasification, as indicated in the title. It was not a review of all alternative energy options.

I did not mean to jump to conclusions but the statement was clearly wrong. I do not mind people discussing bad alternatives like biomass gasification but at this point in time it should be easy to avoid statements that are this much removed from reality. I acknowledge that I might come across as the equivalent of a spelling Nazi here... apologies!
With virgin vegetable oil going for ~25c/lb and biodiesel refineries relatively cheap, Im surprised this fuel keeps on getting the "sweep under the rug".
Diesel moves this planet now and for the foreseeable future.
Although a PV or wind-assisted ship would be a nice break-through.
I agree with that, which is why I think an FT process to diesel is the most logical back half of a biomass gasification unit. That technology is well-developed, and it works. The product diesel will be run in much higher efficiency engines.

In fact, Khosla and I discussed this, and he had two concerns. First, he argued that the emissions from diesel were too high; that it was essentially too dirty. Second, he argued that there isn't enough diesel penetration in the U.S., so he favors a gasoline replacement. My response was that he should take some of that ethanol passion and start arguing for a move to diesel engines in the U.S. Europe has strict environmental laws, and they have embraced diesel engines. We would save a lot of fuel if we did the same.

Choren in Germany have been making some headway into this area: http://www.choren.de
You know where I stand on this topic so there's no point in me hashing out what we've already discussed.  Congrats on the promotion.
Gasification seems obviously the best initial step for carbon feedstocks which could include mixtures of coal and biomass. However pressure swing oxygenators and Fischer Tropsch reactors may be too expensive for small operators so maybe we need 'lo tech' second stages. Examples; using the gas or pyrolysis oil in stationary engines or as furnace fuel. I suspect that soil can only take so much charcoal before it becomes a negative that will have to be dumped in bulk. Still that is a form of geosequestration that might actually work.   Yet another positive is that woody shrub feedstock requires minimal weeding, watering and fertilising compared to oilseeds and food crops.  

I want to post again that these approaches miss a huge problem.

What about roads. They are expensive in energy to build and maintain and although initial construction can use concrete maintenance is based on asphalt. I just don't see us having the extensive road network we have today in a post peak oil world. Most of the roads in America at least will need to be rebuilt to last much longer with a concrete surface since asphalt resurfacing will become increasingly expensive. In general far less money in the form of taxes will be avialable for roads then is avialable today since energy costs are much higher. Thus the utility of a automobile may decrease significantly simply from the lack of a road system like we enjoy today.

In short these alternative fuels cannot address the maintence needs of the infrastructure to support a automible based society they barely can address providing fuel directly for transport. Considering the lifetime of most roads is around 15 years we will be basically roadless within 15-20 years of peak oil.

And this is just the most important structural support required for personal transport. Of course manufacturing costs for cars will rise considerably food costs etc.
So the amount of disposable income will decrease. And in the end the amount of tax money collected will be lower. As we move away from cheap oil there is a real and significant drop in wealth caused by so much of our economy being diverted to fuel production and massive increases in the cost of maintaining infrastructure.

So even if we can make ethanol at a reasonable rate and price I just don't see it as being close to what we need to keep the whole complex infrastructure we have built for automobiles going.

The main reason roads deteriorate is because of 80,000 lbs trucks pound the hell out of bridges and road surface.  About 20 years ago the US DOT determined that degradation of raods/bridges from one 80,000 lbs truck was equal to 3200 automobiles weighing 3500lbs.  Concrete roads would easily last 40 years if trucks did not use them.  Best solution is to get trucks off the highways and onto intermodal trains.
I don't have access to the DOT data but it was at one time reproduced on the Association of American RR's website.

Mark S. Bucol
Engineering Consultant

Simple weathering is sufficient also.
And the congestion is so heavy on most American roads its sufficient to degrade them.

I do agree its possible to build roads that last 40 or more years but we don't have those types of roads at least in the US this means we will be looking at replacing and rebuilding most of our road infrastructure over the next 20 years.

With our without peak oil we are facing this problem right now. In fact there is already a bit of a crisis looming in
the US.


This story is a common theme throughout the US.

I just don't see us even able to maintain our road system in and ethanol economy.

And if we are going to do serious building its far better to put in 100 year electric rail lines like the Swiss are doing.

Construction in general will be very expensive in and ethanol based economy. Things like roads that were subsized by a cheap oil expanding economy are going to especially hard hit in a stagnant expensive ethanol based economy.

The point is low EROI fuel and slow or no growth economies pretty much eliminate the money that subsidized the roads that allowed more growth. And my position is we probably can only sustain a fraction of the road surface we have today.

Also if you try to tax or limit the roads use you will drive people to alternative transportation say trains. Which is a good thing but your maintenance costs for roads are still high so you still need a lot of money for roads. If enough people are switching to trains they will vote for trains over roads.

I figured road construction may be 5-10 times more expensive in a ethanol economy than it is today and of course other expenses will rise at least twofold. Under these conditions trains look awfully good.

I've not seen any real argument that I'm way off base on the costs of roads so I think this ethanol debate is really irrelevant since our road systems will almost certainly unravel and decay within 10-15 years of peak oil.

The only reason I care is I would much rather see us recognize this forget about trying to save the car and pour money and energy into electric rail while its still cheap to build since waiting till after we have failed at ethanol will make it much harder too create a robust electric rail based economy.

I think we basically have one shot at doing power down correctly and if we waste it life will be hard for all of us.

You do have a good point.  If one considers the infrastructure that goes along with a car-based society, one might come to the conclusion that it is not worth saving.  But then again, it does seem like we're going to need some sort of roads.  We can't have a train station in front of every house, and we need some way of transporting goods from the station to the store and from the store to our home.  

Even if it's by horse drawn carriage (a very far fetched idea, admittedly) we're still going to need some sort of roads.  I don't see us going back to dirt roads, especially because it seems like a degraded asphalt road (what we really would have) might actually end up being worse than a dirt road.  

So, maybe smaller, concrete roads will be what we end up with?  For what it's worth, most of the interstate highways I have seen are concrete, so maybe it will take them a bit longer to break down.  

I don't want to pour cold water on your theory but there is the small matter of the Canadian Tar Sands, which are essentially bitumen.

Perfect feedstock for road construction.

Now at a rate of extraction of 3 MBd the tar sands operation has enough resource in the ground to last for hundreds of years.

I see no reason why there wouldn't be enough bitumen to go around the North American continent even if all other wells dried up.

Plus I think you possible over estimate the amount of bitumen needed in road construction.   I think a couple of meduim sized wells could easily keep the US in bitumen if the extraction was managed as a strategic resource.


Its not economical to extract and sell without upgrading.

Actually its the use of natural gas during the upgrade cycle that makes tar sands worth exploiting.

In the past bitumen was cheap since it was a residue or basically waste product of the oil industry this is no longer the case.

I don't think you calculated the cost of using tar sands for paving roads.

From here


Our usage is 75 million tons a year. I'm assuming this is the US alone from the sound of the artical.

The oil sands are about 10-12% bitumen and would need to be processed all the way to the final upgrade with natural gas.

I leave it to you to figure out the economics.

We cannot afford to build roads without cheap oil.

In converting chemical energy of one type to another, such as grain starch to ethanol, some input energy in the form of heat is required.  Some heat is needed to get the yeast to consume the starch (sugar) and thus produce the ethanol as a waste by-product.  RR states that the largest requirement of energy in the starch to ethanol conversion process is separating the ethanol from the water after the fermentation is complete (max of 15% ethanol).  
In line with my first statement about converting energy, power plants that burn coal to produce electricity are only about 40% efficient.  That means that 40% of the BTU's (joules) in the coal are converted to electricity (amps x voltage x time).  The balance of the coal's energy goes up the smoke stack or is transferred to the atmosphere or a river in the power plant's condensor.  The condensor cools the saturated steam (coming from the turbine) to return it to a liquid state so that heat can again be added to the water to produce high pressure steam in the boiler.  So about 54% of the coal's energy is transfered (rejected from the steam cycle system of the power plant) to the atmosphere or river.
If this energy could be used by an ethanol production facility, the EROEI could be greatly improved.  A simple heat pump could extract the heat from the power plant's condensor and transfer it to the ethanol plant's water removal unit. Many refrigerants used in heat pumps can produce temps in excess of 300 deg F, high enough to boil off the ehtanol. Most large scale heat pumps can achieve a COP (coefficient of performance) of 4 or 5, so 5 joules of energy can be produced for every joule of electrical energy used to run the pump.  Thus input energy for the ethanol/water separation can be reduced by 80% from typical nat gas fired operation.
Only problem I see here is locating the ethanol plants next to coal fired power plants.  Natural gas fired combined-cycle plants might not produce enough heat at a continual output to make this work.
Only problem I see here is locating the ethanol plants next to coal fired power plants.  Natural gas fired combined-cycle plants might not produce enough heat at a continual output to make this work.

That is, in fact, exactly what a planned ethanol plant for Montana proposes to do. I think there are some already in operation based on this scheme.

Why not just use CTL then why use biomass ?
The same steam energy can be recovered in a CTL converter.

Not disagreeing with your concept just I think a syn gas based
approach couples better with a steam power plant.

Now it does not matter what you use as a carbon source so if you have a biomass based plant then the same applies just do syngas co-generation with steam from the plants electric generation system. I don't see the need to ferment to ethanol.

Also the next generation coal plants are based on syngas so diverting some of this to produce liquids makes a lot of sense. So I think the best approach is to start with syngas for both electric and fuel generation and reuse the steam to make syngas for both uses.

At worst you may need to upgrade the steam temperature some but your still using the energy put into it to achieve its current temperature in the syngas reaction. Distilling ethanol is wasting this on simply heating more water and your discounting the cost of fermenting. Going strait to syngas puts all the steam energy back into the desired product and you have no fermentation losses.

Finally this appoach is agnostic to carbon sources. Using biomass helps a lot in the C02 balance but on the same hand coal is avialable if needed and the C02 balance can be adjusted elsewhere. I'm not advocating using coal but when your talking about a basic need having coal as a optional carbon source is not something you want too just give up but the fermentation approach does this. As long as the approach is C02 neutral its fine to simply plow some of the biomass back into the fields to offset coal use. This means the carbon is more mobile then when it was buried but you can still be C02 negative. And your not killing your land to produce biomass since its also used as a carbon sink.

I actually figure that if we switch basically completely to electric transport and window and solar power plus some nuclear for making solar panels and rip up most of our roads and replant we might be carbon negative enough to offset global warming. The use of a lot of nukes can be avoided if the solar cell plants are located by hydro-electric plants and of course plastic solar cells would be really useful.
The key is to focus on using dirty energy sources for manufacturing clean energy sources or long lived technology like really good concrete rail system until we reach a critical mass. Biomass solutions will always be at best carbon neutral so we should not focus on them for our primary transportation needs.

The right answer is wind/solar/electric rail its time that we started doing the right thing.

Actually there are many proposals to use power plant thermal energy for residential and commercial heat.  The siting is the problem, unless you go distributed.
  Congrats!! I go to the ethanol plant tommorrow, so soon I'll have a report of sorts.  Eat some hagass.


Dammit, man, its Haggis :-)

And you should try it with neeps & tatties (mashed turnip & poptatoes)


You mean nips and titties.
Yeah, that might work too....;-)
Scotland, eh?

Be sure to visit the island of Jura if you get a chance, George Orwell loved the place! When Orwell visited and then lived there, it had been something like 90% depopulated, the people just left. Orwell was basically able to look around for an abandoned manor, contact the owner, and arrange rental terms. He grew/fished for/hunted/shot all of his food he could, and the hunting-gathering was good. It would be, with 90% of the humans gone!

I'm wondering if it's become all populated again in the worldwide real estate boom, or if Jura has been pretty much in stasis since the 1940s.

"and 1.25 acres can fuel 1 car for a year"

I'm sorry but I find this hard to swallow.

 But I would like to try it. Do I do it by hand or use a tractor/rototiller, etc. ??

I have some acreage ...  what crop would you suggest I plant to make fuel for my car.

I have grown corn , willows , olives ,... have lots of prunings to work with ....

The way I was thinking of it is as follows.

For one car take a half hectare.

each year plant a quarter of your 1/2hectare plot.
After 4 years you'll have planted the whole plot.

At this point your fast growing tree will be ready for felling.

So go back to the first lot of planted trees and clear fell them.  Soon after replant this plot.  Repeat every year forever.

Now, assume that you plant saplings with 1 meter spacings.

In an area of 50m x 25m (the first quarter of your 1/2hectrare) you can (theoretically) plant 1250 saplings.  1 metre spacings for junior trees is reasonable, remember you'll be felling them before they get truely big.

Now if each tree weighs 5.2kg after 4 years, then 1250 of them will five you 6,500kg of wood.  Assume 30% moisture, then after drying you'll have 5,000kg of dry wood.

Find your local wood gas processer, hand over some cash and your 5,000kg of wood and recieve approx 2,170 litres of ethanol back in return.

Put in your pick up truck.  Enjoy.


I  have just got up to replenish my woodstove (3AM).  I stuck a few sticks on a bed of coals and pretty soon - BOOF- the secondary combustion chamber burst into a bright glow as the gas generated in the primary chamber ignited in it.  I adjusted the secondary air a little and got the glow indicating about 1000C- plenty good enough to run my stirling engine (which is still, dad-blame-it sitting in the lab).  Every time I do this little drama, I wonder why it isn't done more widely.  Surely it would be pretty easy to replace at least a portion of domestic oil and gas with biomass pellets for home space heating, freeing up that fuel for vehicles.

Solid fuels are underrated.  And of course pellets allow automatic operation so not everyone need be up in the wee hours. And my computer-adept son tells me it would be trivial to design a good automatic control system so the exhaust would be clean.

Pelletizing takes only a couple of percent of the fuel energy, far less than any sort of liquifacation.

I can easily visualize a vehicle running on pellets or any combination of pellet engine and battery.  And of course there is always that farm tractor running on local biomass.

Thanks for that good info.  Makes me even more eager to get my biomass stirling going ( making good progress, just s  l  o  w.)  I will have to go to Canada and have a look around.

And Robert- have a good time in windy, barren Scotland- my wonderful grandmother was born in Stirling!  I spent some very pleasant time there while my wife was doing her scholarship at Cambridge.

I was totally taken in by your joke about the wood stove- "How could this proven good guy be thinking that this is anything new?".  Then I saw the photo- I've been outrageously duped!

And Robert- have a good time in windy, barren Scotland- my wonderful grandmother was born in Stirling!

I spent some time in Stirling when I was over there. They have a "William Wallace" statue that looks exactly like Mel Gibson. Go figure!

I was totally taken in by your joke about the wood stove- "How could this proven good guy be thinking that this is anything new?".  Then I saw the photo- I've been outrageously duped!

Not everyone figured out the joke, as I got some serious inquiries about this by e-mail. There were 2 purposes in the wood stove example. First, to show how people can be taken in by technical jargon. I think this is why some in the media have proclaimed Kergy's biomass gasification approach a breakthrough in "cellulosic ethanol." They just don't know the difference because it's all technical jargon to them. The problem with that is that it creates unrealistic expectations, like "Now cellulosic ethanol is finally feasible."

Second, I wanted to convey that this is exactly how most patents work. They aren't new inventions from scratch. They are built on previous inventions, and are typically incremental improvements over the status quo. Very few patents are for things like inventing the wheel, yet again this is how some have portrayed the Kergy patent.

Nice piece Robert, thank you for your time.

Just to note that maybe biomass gasification is not that good, because biomass today is mainly another form into which we turn oil to.

By the way, you seem to have a background in chemistry, can you some day write a piece on the basic chemistry of hydrocarbons? I do not recall seeing one here.

Wikipedia is pretty good for that.
By the way, you seem to have a background in chemistry, can you some day write a piece on the basic chemistry of hydrocarbons? I do not recall seeing one here.

Yes, my undegrad degrees are in chemistry and math, and I was 2 years into my chemistry Ph.D. before switching to chemical engineering. I often tell people that my thinking is greatly shaped by the scientist's skepticism that I learned before switching to the chemical engineering department and finishing grad school there.

Hydrocarbon chemistry would be a good topic. I have thought about a whole series on refining as well.

I'm claiming prior art.

Except when I had a Personal Cellulose Reactor, it wasn't that pretty. The glass was black, it had black deposits of something tarry all around the door and there were bark chips, ashes, and the occasional stray wood-boring insect on the floor around it. Congratulations on your good housekeeping.

And congrats on the promotion and relocation!

I'm claiming prior art.

Strangely, I am getting a lot of that. :-) Someone even told me that Ben Franklin actually invented this. But I think mine is better, because I am going to operate in full combustion mode at all times, which is the key to my claim of novelty. I think Franklin's invention sometimes ran in either a fuel-deficient or oxygen-deficient environment. :-)

I think Franklin's invention sometimes ran in either a fuel-deficient or oxygen-deficient environment. Ahh. That may explain all the tarry residue and why it kept setting off my CO detector. But if I run it with the air vents wide open in a mild Texas winter, it makes way too much heat. So perhaps we have some improvements to patent. ;-)

Again congrats on the move. Good to hear you're doing well...

"hand over some cash and your 5,000kg of wood and recieve approx 2,170 litres of ethanol back in return."

1 liter (L) of water weighs 1 kilogram (kg)

By the time I raise the 'cellulose" , cut and chip it, transport it and pay for the digestion etc. ....  

I say the EROEI is not there ...

But I am only a Farmer not an engineer or scientist.

I don't understand the relevance of the 1 litre of water = 1kg comment.

As for EROEI, I was assuming that the land would be tended to as a personal project.  So long as your chainsaw and (rented) pickup truck don't consume more than, say 100 litres of ethanol per (annual) harvest, then your EROEI will be easily 10 to 1.

Looks good to me.

As to planting 1250 trees per year and harvesting 1250 trees per year, I really am suggesting that I'd do this by hand with a shovel.  Yes, I am that mad. :)  It comes down to how much your time is worth to you compared to your desire for a liquid fuel.  In the UK there are plenty of people who raise vegetables in small plots (called allotments) just for the hell of it.  Its probably not time or cost effective compared to purchasing them at the supermarket, but its done as a hobby as much as anything.

From a cost perspective I'm not so sure.  The main issue will be the cost of the biogas - ethanol catalyst capital setup.

Like, I said, its just an idea, it probably wouldn't get past serious analysis.


I don't think very many engineers or scientists, maybe with exception of the few working on cellulose technology itself, are particularly fascinated by the prospects. Being a framer does not disqualify you from having the correct intuitive answer to the question. I would say, quite the contrary, actually.

Here is the problem: an average SUV consumes a couple of gallons of gas a day. A gallon of gas has an energy content of 131MJ/gallon. A well fed human being on a mostly vegetarian diet consumes approx. 2500kcal chemical energy a day with his food. A cal is 4.2J, a kcal is 4200J, thus a human needs approx. 4200J/kcal*2500kcal = 10.5MJ of chemical energy a day. That happens to be the equivalent of 120W of power, not much more than a lighbulb. If follows that with the energy stored in one gallon of gas we could feed 131MJ/10.5MJ = 12.5 people.

The average SUV cosuming 2 gallons of gas a day requires as much chemical energy to operate as 25 people take in with their food!

May I now ask a personal question?

As a farmer, would you feel good about working hard all year long to feed a few dozen SUVs with your land? Especially when you know that the same amount of your produce could feed hundreds of people?

"If follows that with the energy stored in one gallon of gas we could feed 131MJ/10.5MJ = 12.5 people."

For one day ??  feed them what ?  Corn ?

One corn plant a day per person, along with some beans , vegies, etc. will provide enough calories.

So with 1/12 of a gallon of gas I can go out and raise a subsistance diet?

I wonder if this is true ??
   "Solar Energy captured by Photovoltaics can produce
500 times the energy produced by the same area
devoted to crops producing ethanol."

(Source - ASES.org literature)

"For one day ??  feed them what ?  Corn ?"

Any starch or plant protein. That is the stuff that the majority of mankind eats... and that keeps them alive just fine without cardiovascular disease being the norm.

"So with 1/12 of a gallon of gas I can go out and raise a subsistance diet?"

With the equivalent thereof, yes. And not a subsistance diet but one that keeps the doctor away. Just imagine that a gallon of gas has about the same energy as a gallon of olive oil. How much olive oil do you need in your food? How much oil would you need if you could live of nothing else? Oil has 10kcal/g. You need 2500kcal a day, so that makes 250g, less than half a pound of oil a day for energy content.

Plants are fundamentally limited by their photosynthesis chain, so starch, plant protein and plant oils are not that different in their maximum energy yield per acre. Solar cells, by the way, are only limited by thermodynamics. They can, theoretically, achieve some 90% efficiency. 40% has been demonstrated in the lab, 15% you can buy in the mass market.

"I wonder if this is true ??"

The numbers I gave you are roughly correct. A factor of 500 is probably an estimate based on worst case numbers of plant yield and the ethanol process with an EROI of 1.2. So you only get 20% of extra energy out of the plant material, everything else comes from the oil and natural gas needed for nitrate production, transportation, farm equipment, processing, ethanol transportation, blending cost etc.. all of which degrade the theoretical plant yield by another factor of 5 or so...

Face it, corn ethanol is political pork. It was set up to subsidize excess corn production in the US.

Personally, I don't mind supporting farmers living on the best farmland in the world to produce cheap food at all. I think it would be a waste to let that farmland go unused.

But to be honest with you: the US could do a lot better with that corn than to burn it in SUVs... can you imagine how much goodwill food programs in the third world could have created in the past? Instead we burn food for tens of millions in our engines.

In the future they will call that a crime against humanity. Wait... that future is now!

And keep in mind that the average ICE only utilizes 12% of the stored energy content of a gallon of gasoline, or about the amount of energy used to power that same light bulb!!  Why haven't we switched to all electric yet?
I think you have to differentiate between energy and power units and how they relate to efficiency and total energy consumption.

The human body thermalizes 100W of power. It runs at a biochemical efficiency of some 6%, so you get very little mechanical power out of a human being. The caloric burn of the human body is roughly 80-100kcal/hour (2400kcal/day). Once you start working out on a treadmill, exercize bike etc. that burn goes up to 600-1500kcal/h, depending on how fit you are... (I can do some 800kcal/h on my rowing machine and I am far from fit). I know people who can keep this pace up for 12-24 hours... but those are exceptional individuals.

ICE can reach 30-40% efficiency. There are losses in the drivetrains etc.. However, a well designed ICE is far superior to biomechanics in its efficiency.

Most cars do not operate 24/7, like humans do. So the 10kW or so of power that is needed to keep a small car running at 60mph amounts to only 400-500W continuous if we assume a 1 hour average use per day. Still, that is five times more than the energy we need to keep the driver alive. SUVs under American traffic conditions make that 10-20 times more than what the driver needs. And that is where the food/gas equivalent of 25 comes onto play.

InfinitePossibilities said,
"The average SUV cosuming 2 gallons of gas a day requires as much chemical energy to operate as 25 people take in with their food!"

It may seem a minor point,but are we actually using the current "average SUV" as the measuring stick for what we consider the sustainability of at least minimal personal transport?

Even an only moderately imaginative engineer could double the mileage of a current "average SUV" with a little effort, and the effort would be worth it in a full crisis of the "peak oil" type.  A smaller SUV, more in the Kia Sportage class, with hydrualic hybrid drive, and a Diesel engine running on bio Diesel or bottle propane, or electric hybrid of that size using the same prime mover fuel would be probably three to four times more efficient than an "average SUV of current construction, and would stll be a luxury vehicle when compared with my granddad's old 63 pickup....and a giant leap up in luxury in most of the world...I know, it's a minor point, but what is often described as "Peak Oil" can just as easily and justifiably be called nothing more than STUPID WASTE AND BAD DESIGN AND ENGINEERING.

Roger Conner  known to you as ThatsItImout

I meant to talk about what we have right now, not about what is sustainable. I agree... we should be able to live using 10 times the average energy demand of our body. If we don't learn to get there, the future of this planet if rather dark.
Once again, an excellent post.  You speak with clarity, and are gifted with logic and common sense.  Wishing you the best on your next adventure and please don't forget about us.