Review: How Can We Outlive Our Way of Life?

“Have the guts to consider the silent consequences when standing in front of the next snake-oil humanitarian.” Nassim Nicholas Taleb in The Black Swan

I believe our generation faces a sobering choice: Take serious steps to reduce our fossil fuel usage now – and this will undoubtedly entail some amount of hardship – or leave it to our children to face a great deal of hardship. I firmly believe this is our choice, and we must look to solutions that move us in that direction. I also believe that if most people understood that we are pushing a very serious problem onto our children – instead of assuming scientists and engineers will solve the problem – then we would collectively pursue a solution with far greater urgency.

Berkeley Professor Tad Patzek, who has written many articles that are critical of our present attempts to replace fossil fuels with biofuels, has just published a new article in which he also discusses solutions:

How Can We Outlive Our Way of Life? (PDF download)

Many of you know Tad Patzek as the co-author of a number of papers with David Pimentel. If you are pro corn-ethanol, then you have probably been conditioned to discount everything Professor Patzek writes. But even if you disagree with his corn ethanol position, there is still a lot to take away from this paper. Patzek’s conclusion on cellulosic ethanol is the same as my own: The status of cellulosic ethanol has been exaggerated and over-hyped, and the solution that we really ought to be pursuing is electric. The abstract of the paper reads:

In this paper I outline the rational, science-based arguments that question current wisdom of replacing fossil plant fuels (coal, oil and natural gas) with fresh plant agrofuels. This 1:1 replacement is absolutely impossible for more than a few years, because of the ways the planet Earth works and maintains life. After these few years, the denuded Earth will be a different planet, hostile to human life. I argue that with the current set of objective constraints a continuous stable solution to human life cannot exist in the near-future, unless we all rapidly implement much more limited ways of using the Earth’s resources, while reducing the global populations of cars, trucks, livestock and, eventually, also humans. To avoid economic and ecological disasters, I recommend to decrease all automotive fuel use in Europe by up to 6 percent per year in 8 years, while switching to the increasingly rechargeable hybrid and all-electric cars, progressively driven by photovoltaic cells. The actual schedule of the rate of decrease should also depend on the exigencies of greenhouse gas abatement. The photovoltaic cell-battery-electric motor system is some 100 times more efficient than major agrofuel systems.

The paper is highly technical, which will turn off many people. But what I enjoy – and I believe is one of my strengths – is to distill technical information and present it so that it is more readily digestible for the layperson. My hope is that this essay succeeds in doing that.

The paper was presented at the 20th Round Table on Sustainable Development of Biofuels in Paris, and therefore contains a lot of Europe-specific discussion and recommendations. The paper covers a lot of ground. Petroleum depletion is discussed, and the business-as-usual scenario is discarded as simply not possible. Cellulosic ethanol is covered, with a close examination of the energy efficiency of Iogen‘s plant in Ottawa. This result is then compared to the energy efficiency claims of the six proposed demonstration plants in the U.S. The last section compares the potential of photovoltaic cells to biofuels for mitigating our depleting fossil fuel reserves.

Summarizing the Paper


In the introduction, Professor Patzek states that world production of conventional petroleum peaked in 2006, and will decline exponentially within a decade. He suggests that heroic measures such as infill drilling, horizontal wells, and enhanced oil recovery methods can stem the decline initially, but this will lead to a steeper decline rate later on. He extrapolates the current per capita use of petroleum with the growth of population in the U.S., and concludes “that the US and the rest of the world soon will be on a head-on collision course.” He also states that the U.S. currently uses 33 times as much energy in transportation fuels than is required to feed the population.


In this section, Professor Patzek outlines five constraints that impact humanity’s survival, followed by possible solutions given these constraints. The constraints include exponential population growth, overuse of the earth’s resources, and our current political structure in which “more is better.” He presents two solutions to our current situation: 1). Go extinct; or 2). Fundamentally and abruptly change. The status quo is not an option, as Patzek believes it will lead to solution (1). I understand that many doubt that (2) is possible, which is why they believe we are doomed. Personally, I believe the most likely solution is a combination of the two. People will go extinct as food and energy become unaffordable (this is happening even now), but there will be pockets of fundamental and abrupt change. Fast recognition and adaptation – both on a personal and governmental level – are going to be very important.

Patzek examines the impact of fossil fuel usage on population growth, and concludes that of the present world population, “4.5 billion people owe their existence to the Haber-Bosch ammonia process and the fossil fuel-driven, fundamentally unstable ‘green revolution,’ as well as to vaccines and antibiotics.”

He comments that too many in society consider themselves more knowledgeable about energy matters than they really are, and this is why we aren’t urgently confronting the problem. As his 2nd conclusion of the paper, he writes:

Business as usual will lead to a complete and practically immediate crash of the technically advanced societies and, perhaps, all humanity. This outcome will not be much different from a collapse of an overgrown colony of bacteria on a petri dish when its sugar food runs out and waste products build up.

He concludes this section by pointing out that we have been conditioned to think that technology is almost magic and will solve our problems. He quoted a biofuels expert who suggested “Biotechnology is not subject to the same laws of chemistry and physics as other technologies. In biology anything is possible, and the sky is the limit!”

Efficiency of Cellulosic Ethanol Refineries

This section was extremely interesting to me. Real energy efficiencies of cellulosic ethanol plants (which presently exist only on paper or in demonstration scale) are hard to come by. Those 4:1 or 8:1 energy returns that you often see claimed are hypothetical; nobody in the cellulosic ethanol business has demonstrated anything like this. Professor Patzek attempts to shed some light on this subject. In his words:

I start from a “reverse-engineering” calculation of energy efficiency of cellulosic ethanol production in an existing Iogen pilot plant, Ottawa, Canada. I then discuss the inflated energy efficiency claims of five out-of-six recipients of $385 millions of DOE grants to develop cellulosic ethanol refineries.

Using published information, Professor Patzek calculated the efficiency of the Iogen plant. He defined the efficiency (albeit by an equation that could have been more clear) as the BTUs of ethanol produced, divided by the theoretical maximum. His calculated efficiency of the process was 20%; input 1 BTU into the process and return 0.2 BTUs, for a net of -0.8 BTUs. This calculation is in the same form as Dr. Wang’s gasoline efficiency calculations – the initial BTUs of the feedstock are counted as an input into the process, and then the processing energy is counted against it. In simple terms, if you take 1 kilogram of wheat straw, add in the distillation energy and take credit for the heating value of the lignin, you have the denominator of the equation. The numerator is the heating value of the ethanol that was produced from that kilogram of wheat straw. If you started with 1 BTU of straw, and produced 1 BTU of ethanol, the efficiency is then governed purely by the distillation energy (essentially the amount of external energy required to drive the process).

Of particular note, the equation did take a credit for the lignin, which is always the assumption that cellulosic ethanol proponents use to obtain inflated energy returns. However, the most significant piece of the calculation for me – and one that Patzek did not call attention to – is that if you look at only the distillation energy (the 2nd term in the denominator of Eqn 1), it is 55% greater than the ethanol that is yielded from the distillation. That means that production of 1 BTU of cellulosic ethanol requires a distillation step that consumes 1.55 BTUs.

The reason for this is one I have stated numerous times. As Patzek writes “there is ca. 4% of alcohol in a batch of industrial wheat-straw beer, in contrast to 12 to 16% of ethanol in corn-ethanol refinery beers.”

I do note that if you take full credit for the heating value of the lignin, it just barely satisifies the distillation requirement. If you run through the math, the lignin BTU credit gives an energy balance of 1.05, which is worse than the 1.3 of corn ethanol plus by-product credits. But remember, the lignin in the process is not dry. It is very wet. Drying co-products in a corn ethanol plant requires a substantial input of energy. If lignin is to be used in a cellulosic ethanol plant, it will have to be dried.

Furthermore, even if the lignin is dry, no other energy inputs into the process have been considered (so this is not a complete energy balance calculation). In other words, if those inputs were all free (of course trucking the biomass back and forth will require significant energy inputs), and the lignin was dry, you would get 1.05 BTUs of cellulosic ethanol out for a lignin input of 1 BTU. Even presuming that Iogen has made major advances recently, it is not surprising why they have been slow to build a commercial facility; they know the score. Patzek concludes:

The Iogen plant in Ottawa, Canada, has operated well below name plate capacity for three years. Iogen should retain their trade secrets, but in exchange for the significant subsidies from the US and Canadian taxpayers they should tell us what the annual production of alcohols was, how much straw was used, and what the fossil fuel and electricity inputs were. The ethanol yield coefficient in kg of ethanol per kg straw dmb is key to public assessments of the new technology. Similar remarks pertain to the Novozymes projects heavily subsidized by the Danes. Until an existing pilot plant provides real, independently verified data on yield coefficients, mash ethanol concentrations, etc., all proposed cellulosic ethanol refinery designs are speculation.

Patzek then addresses the six proposed cellulosic ethanol plants that were awarded $385 million USD by the US Department of Energy. For reference, he gives the energy efficiency of Sasol’s coal-to-liquids (CTL) process as 42%, the efficiency of an average oil refinery as 88% (and I can verify that this number is spot on), and that of an optimized corn ethanol refinery as 37%.

Figure 1. Inflated Energy Efficiency Claims of Announced Cellulosic Ventures

Figure 1, from Patzek’s paper, compares the claimed efficiencies of the various cellulosic ventures. Of the six proposed plants, only Abengoa, reporting 25% estimated energy efficiency, was close to Patzek’s reverse-engineered efficiency for Iogen. The other five all claimed energy efficiencies in the 40-60% range. The most optimistic was Vinod Khosla‘s former Kergy (now Range Fuels) venture. See the last section of Cellulosic Ethanol vs. Biomass Gasification for some discussion on Kergy. This process is actually a gasification process, and as such won’t have the same sorts of issues that Patzek documented for Iogen. But I don’t think in an apples-to-apples comparison they can beat a CTL process on efficiency, because it is much easier to handle coal than biomass (not that I endorse CTL). They are also going to have one problem that the others don’t, and that is the production of significant amounts of various mixed alcohols.

There are theoretical reasons why cellulose is unlikely to produce an ethanol concentration in the range of corn ethanol. Patzek writes that at “about 0.2 to 0.25 kg of straw/L, the mash is barely pumpable“, and states that this straw concentration will result in a fermentation beer of 4.4% ethanol at a maximum. Yet five of the proposed plants are claiming energy efficiencies that are as great or greater than those of corn ethanol plants.

Where Will the Agrofuel Biomass Come From?

In this section, Patzek tackles an issue that I have also addressed: Where could we get that much biomass to begin with? Patzek asks and answers: “Where, how much, and for how long will the Earth produce the extra biomass to quench our unending thirst to drive 1 billion cars and trucks? The answer to this question is immediate and unequivocal: Nowhere, close to nothing, and for a very short time indeed.”

In the interest of brevity, I won’t go into the details of this section. It is a discussion of Net Primary Productivity and Net Ecosystem Productivity, as well as the USDA/DOE billion ton vision – Biomass as feedstock for a bioenergy and bioproducts industry: The technical feasibility of a billion-ton annual supply (PDF download). The short of it is that Patzek argues that the biomass is simply not available, and attempting to grow and process enough biomass to continue the business-as-usual model “would be a continental-scale ecologic and economic disaster of biblical proportions.”

Photovoltaic Cells vs. Agrofuels

The analysis of Iogen’s energy balance and this final section were for me the gems of this paper. In this section, Patzek looks at a square meter of land, and compares the energy potential of various biofuels, solar power, and wind power. He also shows the amount of energy if this square meter was an oil field producing oil for 30 years, but that limits the discussion to a very small fraction of the earth’s surface. Also, as Patzek wrote, “this resource is finite and irreplaceable and after 30 years there is no producible oil left in it.” So, I am not going to focus on the oil comparison in this section.

For his comparisons, Patzek looked at photovoltaic cells, wind turbines, corn ethanol, sugarcane ethanol, corn stover ethanol, and Acacia and Eucalyptus for FT-diesel, ethanol, or electricity. He uses the actual demonstrated solar capture efficiency of these processes. Figure 2 shows how the various sources stacked up:

Figure 2. Professor Patzek’s Comparison of Various Renewable Options

As shown in the figure, based on Professor Patzek’s methodology solar PV is the only option considered that has a legitimate chance to offset a fair portion of our current oil production. Wind came in a distant second. Of the biomass applications, Acacia for electricity ranked the highest. It is significant to note that the top three options all involved production of electricity.

Interestingly, while the solar capture of sugarcane ethanol ranked lower than those three options, Patzek comes to the same conclusion that I did in my essay Brazilian Ethanol is Sustainable. He writes:

Because of the unique ability of satisfying the huge CExC [RR: Defined as cumulative exergy consumption] in cane crushing, fermentation, and ethanol distillation (0.41 W/m2), as well as fresh bagasse + “trash” drying (0.27 W/m2), with the chemical exergy of bagasse and the attached “trash,” sugarcane is the only industrial energy plant that may be called “sustainable.”

Patzek also performs a calculation designed to show how much area is needed to drive a hypothetical car 15,000 miles per year on some of the energy options. He concludes that “for each 1 m2 of medium-quality oil fields one needs 620 m2 of corn fields to replace gasoline with corn ethanol and pay for the free energy costs of the ethanol production. Similarly, one can drive our example cars for one year from ~30 m2 of oil fields, 90 m2 of photovoltaic cells, 1100 m2 of wind turbines, and ~18000 m2 of corn fields.”

However, one key item not addressed in this essay – and for me the key to making this vision work – is improving energy storage technology. Patzek presumes continued improvement of battery technology. In fact, he writes “With time the batteries will get better, and electric motors will take over powering the vehicles.” Is that a reasonable assumption? I don’t know. I would have liked to have seen this explored in a bit more detail. One hopes that this isn’t a situation in which Patzek is presuming “those guys will figure it out.”

Professor Patzek’s Conclusions

I will let Professor Patzek’s conclusions speak for themselves. Here are some excerpts:

In this paper I have painted a radical vision of a world in which fossil fuels and agrofuels will be used increasingly less in transportation vehicles. Gradually, these fuels will be replaced by electricity stored in the vehicle batteries. With time the batteries will get better, and electric motors will take over powering the vehicles. The sources of electricity for the batteries will be increasingly solar photovoltaic cells and wind turbines. The vagaries of cloudy skies and irregular winds will be alleviated to a large degree by the surplus batteries being recharged and shared locally, with no transmission lines out of a neighborhood or city.

I have shown that even mediocre solar cells that cost 1/3 of their life-time electricity production to be manufactured are at least 100 times more efficient than the current major agrofuel systems. When deployed these cells will not burn forests; kill living things on land, in the air, and in the oceans; erode soil; contaminate water; and emit astronomic quantities of greenhouse gases.

Finally, no future transportation system will allow complete “freedom of personal transportation” for everyone. I suggest that good public transportation systems will free many, if not most people from personal transportation.

My Conclusions

I am not sure whether Professor Patzek believes that biofuels have no place at all among our future energy options. In my opinion, there is a place for them, albeit in niche applications and not as a major energy source. I think we will continue to have a need for some long-range transportation options (e.g., shipping, airline transportation) that would be difficult to electrify. But for the most part, the future has to be electric. The sooner we shift focus from biofuels to electric transportation, the better.

33 thoughts on “Review: How Can We Outlive Our Way of Life?”

  1. Robert,

    As someone who has debated Tad Patzek, I think his views about biofuels are less important than the remarkably pessimistic view he has of humanity’s future that results from his methodology. He and his mentor and sometime co-author David Pimentel seem to believe that the planet’s human population has long since overshot its carrying capacity and that renewable energy can play only a minor role in meeting our energy needs.

    This is where the debate should take place, not about the application of his thermodynamic methodology to what all but Vinod Khosla thinks will be a tiny slice of our energy future.


    David Pimentel has written, “the optimum(world) population should be less than…2 billion”( David Pimentel and Marcia Pimentel, Land, Energy and Water: The Constraints Governing Ideal U.S. Population Size. Negative Population Growth. 2004.) and “For the United States to be self-sustaining in solar energy, given our land, water and biological resources, our population should be less than 100 million…”( David Pimentel, Xuewen Huang, Ana Cordova, Marcia Pimentel, Impact of Population Growth on Food Supplies and Environment. Presented at the American Academy for the Advancement of Science Annual Meeting, February 9, 1996. Citing David Pimentel, R. Harman, M. Pacenza, J. Pecarsky and M. Pimentel, “Natural resources and an optimum human population”, Population and Environment. 1994.)

    Patzek’s writings on thermodynamics would seem to lead him to the same conclusion. He and Pimentel, in a co-authored piece recently concluded,“We want to be very clear: solar cells, wind turbines, and biomass-for-energy plantations can never replace even a small fraction of the highly reliable, 24-hours-a-day, 365-days-a-year, nuclear, fossil, and hydroelectric power stations. Claims to the contrary are popular, but irresponsible…new nuclear power stations must be considered.”(Tad W. Patzek and David Pimentel, “Thermodynamics of Energy Production from Biomass,” accepted by Critical Reviews in Plant Sciences, March 14, 2005)

    David Morris

  2. Harsh opening for trying to do good in this world from Nassim Nicholas Taleb. Sounds like someone has an axe to grind…

    Range Fuels’ technology has been tested and proven in bench and pilot-scale units for over 7 years. Over 8,000 hours of testing has been completed on over 20 different non-food feedstocks with varying moisture contents and sizes, including wood waste, olive pits, and more. This technology will be used in our first plant planned for a site near Soperton, Georgia.

  3. However, the most significant piece of the calculation for me – and one that Patzek did not call attention to – is that if you look at only the distillation energy (the 2nd term in the denominator of Eqn 1), it is 55% greater than the ethanol that is yielded from the distillation. That means that production of 1 BTU of cellulosic ethanol requires a distillation step that consumes 1.55 BTUs.
    This is exactly why I believe all ethanol-based fuels schemes are hogwash. Thanks for summarizing it so well!

  4. People will go extinct as food and energy become unaffordable (this is happening even now)
    Oh, it is? Where would that be? Not Zimbabwe, where starvation is completely political, thanks to the tyrant Robert Mugabe. Not Sudan, where the government is implicated in ethnic cleansing. Where on earth has food and energy become unaffordable, other than the direct deeds of evil politicians?

  5. Where on earth has food and energy become unaffordable, other than the direct deeds of evil politicians?

    I wasn’t thinking of those examples when I wrote that. I was thinking of people who die during a cold snap or heat wave. Some of them die because they are concerned about finances, so they risk keeping it hotter or cooler than is safe. I know that firsthand. Some try to tap pipelines and die.

    I am not saying there aren’t other factors, but if oil prices continue to go up, there will be casualties.

  6. Range Fuels’ technology has been tested and proven in bench and pilot-scale units for over 7 years.

    In fairness to you (and I should go back and make this clear, as I have done so before), your technology is different. I don’t consider it a cellulosic process. It is gasification, which I do think has a much brighter future.

    You should have an efficiency advantage over the wet cellulosic processes, but I don’t think you will get the efficiency being claimed.

  7. Robert – great find. I read the paper over lunch. Over time, I have come to the same conclusion more or less. Solar power is the answer, either capturing it or producing the power of the sun on earth (fusion).

    Perhaps I missed it, but Patzek didn’t talk about nuclear power. Surely the energy returned on uranium production has to far exceed its energy input. But even uranium is a finite resource, perhaps one with a much longer peak though.

  8. Range Fuels’ technology has been tested and proven in bench and pilot-scale units for over 7 years.

    I went back and made a note on Range Fuels in the essay. While you won’t have a lot of the problems that the straight cellulosic guys will – and I do think that overall you are far better off than they are – you are going to have the mixed alcohols issue to deal with. Unless you can sell the product as mixed alcohols (and I know someone who claims the patents on a wide range of mixed alcohols), then you have a challenge separating them and selling them as separate products.

  9. Perhaps I missed it, but Patzek didn’t talk about nuclear power. Surely the energy returned on uranium production has to far exceed its energy input. But even uranium is a finite resource, perhaps one with a much longer peak though.


    You’re right — there will be a Peak Uranium just as there is a Peak Oil, Peak Coal, and Peak Biomass. The ultimate answer has to be fusion power. Once we have safe, operable fusion reactors, there will be no bounds on how much energy we can consume.

    If the situation is as desperate as Patzek says, we should be moving with all deliberate speed and concentrating our resources and brain power on solving the problem of controllable fusion energy. Practical fusion power should be today’s Manhattan Project and Race-to-the-Moon.


  10. Surely the energy returned on uranium production has to far exceed its energy input.

    The other issue there is that it gives us one more electrical option. If we had an electric transportation infrastructure, we could start to transition from coal and natural gas based electricity to solar, wind, nuclear, etc. A predominantly liquid-fuel infrastructure really limits us.

  11. Thank you for your comments Robert. Some people do not account for the technology X factor in all of this. Tad is thinking of right now and yesterday. New efficent breakthroughs will happen, they are in the pipleline as we speak. Tad and David should be trying to help us find ways to become energy independent, instead of a hatchet job on Vinod Khosla. We need to be responsible and villigent to a changing a way of life that some do not like.

    As George Bernard Shaw said, “Liberty means responsibility. That is why most men dread it.”

  12. Robert,
    Why is Range Fuels going to use gasification/F-T to produce alcohols? Wouldn’t it make sense to rather produce green diesel and gasoline? Is this Uncle Sam distorting the market to give us an inferior product, based on his limited grasp of thermodynamics?

  13. “I believe our generation faces a sobering choice: Take serious steps to reduce our fossil fuel usage now – and this will undoubtedly entail some amount of hardship – or leave it to our children to face a great deal of hardship.”

    It’s taken more than a generation to put us in this position, and certainly more than a single country or a single culture. For the last century or so, every country that could climb the growth curve using fossil fuels did it.

    I’m really afraid we won’t see the kind of unanimous pull-back we’d need to make global pre-adaption work. Models and predictions just aren’t that convincing.

    So we’ll get a messy migration to “new energies” and “new lifestyles” over time. Some families, cultures, and nations will adapt early and miss some of the pain … but not all will.

    It becomes what we call in engineering a race condition:

    “A race condition or race hazard is a flaw in a system or process whereby the output of the process is unexpectedly and critically dependent on the sequence or timing of other events. The term originates with the idea of two signals racing each other to influence the output first.”

    Adaptation races the oil supply/demand squeeze.

    Which will win? Nobody knows.

    (Though surely, chance favors the prepared.)

  14. Robert

    Great article. I think every politician needs to understand this, and understand that the future is, as you say, electric.

    I think the EROEI of gasoline is way overstated. Does this calculation make sense?
    A gallon of oil has 138,000 BTU. The stated efficiency of an oil refinery is 88% which brings it down to 121440 BTU, with refining consuming 16,560 BTU. We’ll say a gasoline engine is about 25% efficient, which means that 30360 BTU are useful. The useful energy divded by energy invested is 1.83.

    PHEVs on solar, wind, geothermal, ocean, hydro, nuclear would have a much higher useful energy ratio.

  15. Adaptation races the oil supply/demand squeeze.
    I think it should be: Adaptation is forced by the oil supply/demand squeeze.

    Clearly the “oil supply/demand squeeze” has not pushed hard enough, as of yet. But it will.

    The free market will work this out, as long as those oxygen depleting sources of hot air in Washington can keep from interfering…

  16. Clearly the “oil supply/demand squeeze” has not pushed hard enough, as of yet. But it will.

    Some of us are pre-adapting, before prices “force us.”

    The thing is, some of those adaptations are clearly non-market.

    Why do I have more “eligible renewables” on my power bill than midwesterners? Because voters in California said it should be that way.

    Others clearly are market responses, as with WalMart’s drive to reduce energy consumption.

  17. Dear Robert,

    Thanks for having the courage to say this…..

    “But for the most part, the future has to be electric. The sooner we shift focus from biofuels to electric transportation, the better.”

    I agree. I live in “H” town, if you know what I mean. Many of my relatives work or have worked in the oil and gas industries. I’m sure you understand.


  18. Someone picked up on what I was saying.

    While all these doomsday predictions in the media are of little comfort to investors in corn-based ethanol, we still have some faith. New technology being developed in the labs of startups promises to offer efficient, market-supported, non-corn based alternatives. If that can happen in a relatively short time frame (the next few years), we may very well have another ethanol boom on our hands.

  19. Why do I have more “eligible renewables” on my power bill than midwesterners? Because voters in California said it should be that way.

    Why do Texans have more choices than Californians?

    Power to Choose

    Because Texas gives its consumers choices instead of mandating solutions.

  20. Well let me ask you this … the Germans are working on some crazy goal to be using 50% renewable energy in 2050. That is obviously not purely a market solution.

    Do you think we will laugh at the Germans in 2050 because they adapted too soon?

    Or will we think we should have done more?

    As an observer, and not a ideologue, I think that both we and German have regulated market economies. We balance them slightly differently, while the real ideologues pretend that we are (or can be) pure-market or pure-regulation.

  21. The answer to our “oil dependency” is simple. Just get rid of the internal combustion engine.

    Do you think Toyota installed an electric motor in its Prius hybrid because the gas powered motor was more efficient than the electric engine? Or vice-versa….

    All the recent bio-fuels flap amounts to no more than arguing about which model of casket will be used to bury the the internal combustion engine.

    Throw the ICE in the trash-can and 90% of all energy problems disappear instantly.

    Vast quantities of liquid hydrocarbons (oil and gas) will be left behind

    in the ground, just as solid hydrocarbons (coal) are being left behind today.”

    —Chris Gibson-Smith, Managing Director, BP,

    25 Sept. 1998

    “Thirty years from now there will be a huge amount of oil—and no buyers. Oil will be left in

    the ground. The Stone Age came to an end, not because we had a lack of stones, and the Oil

    Age will come to an end not because we have a lack of oil.”

    Sheik Yamani, former Saudi Oil Minister *2000


  22. Patzek seems to have completely ignored nuclear power. While I wouldn’t want to live in such a world, we could continue to increase our population and our consumption fueled by nuclear fission alone for 1000s years. This is why I really don’t think we have just the two choices. I expect there’s a middle ground where we continue to industrialize the rest of the world, bringing the entire (projected 9 billion) population up to first-world living standards, level off our population, and go forward from there.

  23. I distillation the only practical way to concentrate ethanol? Is there any hope of a more efficient process using reverse osmosis?

    How about partitioning into a non-polar solvent, doing fractional distillation on that, and reusing the solvent?

  24. Robert, batteries are “good enough”, in PHEV’s. Even lead-acid will do just fine in a PHEV: they’re cheaper than gasoline when gas hits $.175/gallon. A PHEV-40 will displace 75-99% of fossil fuel usage, depending on usage pattern. That’s enough for the moment, and of course battery capacity will grow as batteries get cheaper.

    Professor Patzek’s analysis of wind is a bit superficial. It’s important to remember that a wind turbine may need 60 acres to prevent “shadowing” (interference between turbines), but the turbines don’t “consume” that 60 acres. For instance, on a farm a turbine may “consume” about 1/4 acre for access roads and the turbine itself, leaving 99.5% of the land for farming. The same thing applies off-shore. The important thing is total resource (72TW average), E-ROI (40+), and cost (4-8 cents/kwh), all of which are perfectly good. So, wind is perfectly viable. Further, wind is competitive even now with natural gas, and wind can ramp up more quickly. Solar will be cost-competitive, and scale up, but it isn’t quite there yet.

    Let’s do the calculations: An average light vehicle (sedan, pickup, SUV) would take .35 kwh/mile (Patzek’s figure). The average US vehicle is driven 12,000 miles (Patkek’s figure is too high), which gives us 4,200 kwh’s/yr, or an average of .48 KW.

    A 3MW wind turbine might take, generously, .5 acres (about 2,150 sq m) for access roads and the turbine itself, and generate an average of 900KW, or .42KW per sq m.

    That gives us 1.1 sq meters of wind turbine per vehicle, or 1/30 of that of oil. Not bad.

    I have to say that if this is an example of the rigor of Professor Patzek’s work, I’m beginning to have some sympathy for bio-fuel advocates who have been criticizing his work for some time. I don’t mean to suggest that I think that bio-fuels can scale up, but bio-fuel advocates keep saying that Patzek & Pimental are very careless with their calculations of E-ROI, and this certainly is an example of woefully careless calculations.

    I think the bottom line here is that limits to available acreage are very important for plant-based fuels, and unimportant to everything else (oil, solar, wind, nuclear, etc).

    Dmorris: I don’t see any physics based energetic limit to human population.

  25. Dmorris, I begin to understand Patzek’s unrealistic pessimism. he’s relying on this book:

    Hayden, H. C. 2002, The Solar Fraud: Why Solar Energy Won’t Run the World

    It’s quite unrealistic. If I believed it, I’d be pessimistic, too.


  26. Optimist said…
Why is Range Fuels going to use gasification/F-T to produce alcohols? Wouldn’t it make sense to rather produce green diesel and gasoline? Is this Uncle Sam distorting the market to give us an inferior product, based on his limited grasp of thermodynamics?


    What Optimist possibly doesn’t realize is first that F-T isn’t the GTL process utilized to produce higher mixed alcohols. This GTL process is something simpler called “methanization” – whereby C1 methanol molecules are catalyzed and then build upon each other before this highly specific GTL synthesis reaction is completed.

    Two methanol molecules smashing together equal a synthetic ethanol. That C2 ethanol is catalytically smashed with another C1 methanol and becomes a C3 (n) propanol. The propanol grows into a C4 (n) butanol, C5 (n) pentanol, C6 (n) hexanol, C7 (n) heptanol and C8 (n) octanol in a declining reaction curve. The (n) stands for “normal” or straight-chain molecular configuration.

    This fuel blend is something which when diluted in water becomes “bug food” or “plant food.” No “isos” or hybrid (more complex) molecules here and mother nature’s organisms and green brush or trees consume this synthetic fuel blend as a food source which dilutes evenly in water.

    Oxygen makes this happen. This fuel is appropriately termed “oxycarbon” vs: traditional hydrocarbons such as petroleum-derived fuels and ground coal.

    This is the basic and least understood difference in fuel chemistry. Adding a oxygen atom to the fuel’s recipe (an oxygen atom which was derived from boiling H2O into steam) is the 3rd grade chemistry behind this GTL synthesis reaction which is definately NOT to be confused with cellulosic ethanol fermentation utilizing extra expensive, extra acidic enzymes as the first step in order to convert lignin into sugars for yeasts to consume in the secondary fermentation step.

    Finally: This blend of higher alcohols performs much better and exhibits 20% more Btu’s than does corn-derived ethanol or 45% more Btu’s than does C1 methanol which was the source of it’s GTL synthesis beginnings…

    Khosla’s group has used the current buzzword of “cellulosic” to obtain their recent Federal DOE grant to assist construction costs of Range’s new Georgia GTL gasification front-ends plant. The only reason to “hook” such novel GTL processes into the cellulosic arena is because his group is going to isolate the basic building block Btu’s of elemental carbon by gasifying wood waste.

    Otherwise they’d focus on gasifying coal, petcoke, sewer sludge, ground tires, etc., as alternative and greater Btu substrates as the front-ends to this GTL process which is NOT Fischer-Tropsch.

    The secret here will be to utilize this new, strong synthetic blend of biodegradable fuel alcohols as either a petroleum blendstock OR a coal cleaning and slurry agent. The third usage for this blend will be as a stand-alone neat fuel.

    These higher alcohols radically improve the conventional hydrocarbon combustion dynamics of internal combustion engines, jet turbines and coal-fired steam boilers producing electricity. Robert earlier mentions something about patents for these synthetic blends of higher alcohols and their resulting usages.

    Conversely, the Fischer-Tropsch GTL reaction produces a long, straight-chained paraffin wax which needs expensive hydrocracking in order to break C40 or C60 waxy chains down into something resembling diesel or syndiesel. This resulting sulfur-free syndiesel is very expensive to produce and unfortunately, it still floats on this planet’s water bodies just like the Valdez oil spill did and still does in Alaska’s Prince William Sound.

    The extra hydrogen needed to hydrocrack these F-T paraffins into shorter molecules has got to come from someplace. And when hydrogen is isolated from fossil methane through steam reformation or gasified coal/biomass, etc. – a comparable stream of CO2 greenhouse gas is created which is typically vented to the atmosphere.

    Fischer-Tropsch syndiesel production is EXPENSIVE and typically dumps a lot of waste CO2 to the atmosphere.

    To further hydrocrack the paraffins or diesel chains into shorter kerosene-based jet fuel – about 2x the amount of reactive hydrogen is needed. To break these molecules down even shorter resembling gasoline – then 3x to 4x the amount of raw hydrogen is needed. This is why we hear about CTL to produce syndiesel – we don’t hear much about CTL to produce jet fuel or kerosene. Simply the extra volumes of very, very expensive hydrogen which is needed.

    Robert: Thank you for your replay of Prof. Patzek’s newest published paper with appropriate links. I found it to be most interesting.

    Gary Bridge

  27. Professor Patzek’s analysis of wind is a bit superficial.

    You can say that again. To equate land impact of wind turbines separated by hundreds of meters with solar panels which completely cover the ground is beyond silly. Unfortunately it’s all too typical of Patzek, who seems happy to distort data whenever needed to support his viewpoint. I actually agree with many of Patzek’s conclusions about biofuels and electric drive, but I find his methods repugnant.

    Solar may one day be cheap enough to deploy widely, but wind is here now. The US has ample wind resource to power 200 million PHEVs, and the economics are extremely favorable. $100 billion invested annually in PHEVs and wind farms would save the US $300 billion a year in oil imports plus another $200 billion per year in military spending. It’s a no brainer, and it burns me when opinion-makers like Patzek confuse the matter with distortions and outright lies.

  28. an interesting post over at gristmill talks about innovation in the solar market.

    my cynical and unfair summary of it is that vendors of current systems are happy that there have not been any crazy new breakthroughs … because they are trying to sell current systems.

    the interesting general question is, when facing resource depletion, when is the optimal time to shift?

    do you put all your eggs in the current-tech basket? in the future-tech basket? or do you try to balance both?

    (i guess i’d look for balance)

  29. Gary,
    Thanks for that description, it was really enlightening. Do you have references you can point us to? Sounds like Range Fuels may be worth keeping an eye on.

    I guess the one thing that is still a bit confusing is the terminology. Seems like some use the term “methanization” for the production of methane (natural gas) from syngas. It seems like the process you describe would more accurately be termed “methanolization” followed by “catalytic condensation“.

    You make a great point about the biodegradability of higher alcohols versus crude oil (not sure I would call higher alcohols plant food, but that’s neither here nor there).

  30. An anonymous poster said
    “batteries are “good enough”, in PHEV’s. Even lead-acid will do just fine in a PHEV: they’re cheaper than gasoline when gas hits $.175/gallon.”

    I don’t know where you are getting your numbers from, but a 40 mile range would require a lot of lead-acid batteries. That range deteriorates every time you recharge. I believe that you would be buying a new battery pack before you covered the extra cost with gas savings. Not to mention the cold weather problems.

    I attended a EV battery symposium recently, it was suggested that a 10 mile range would be possible soon. Meaning that you would barely break even (with gas savings) before you needed to replace the battery. This would be using currently (or soon to be) available lithium ion cells. There are some safety issues being worked out.

    If you could do it with lead-acid, many people would be doing it.

  31. Dennis Moore is correct, lead acid is a poor match for PHEVs. The Chevy Volt battery pack is about 160 kg for 16 kWh, which already pushes the boundaries. 16 kWh of lead acid would be 500 kg. Even at that size, a lead-acid pack would not provide competitive acceleration nor last the life of the car. Regular lead-acid lasts 500 cycles, about a year and a half for a PHEV. $2000 or so every 18 months more than offsets any gasoline savings. Deep cycle batteries last longer, but cost even more.

    Here’s some very rough PHEV battery specs:

    100 Wh/kg
    1000 W/kg
    4000 cycles
    10+ years
    -40 degF to +120 degF

    NiMH today can come close on energy OR power density, but not both in the same cell. NiMH also falls short on cycle life and “high power” NiMH as used in today’s hybrids cost $1000+/kWh. Regular li-ion dies after 500 cycles and has temperature problems. Advanced lithium chemistries from companies like A123Systems and AltairNanoSytems are the first cells to meet the specs (except cost, which should come down with high volume).

    The only lead acid cell which might come close is being developed by Firefly, a startup spun out of Caterpillar. They replace the lead grids with a “graphite foam”. Even if they fall a little short on energy and/or power density, they’ll more than compensate with extremely low cost ($100-ish/kWh).


    The Army’s new family of 15 different manned ground vehicles or MGV’s will be powered by electric motors. These vehicles are huge and weigh in at 22 to 28 tons each, They include an Armed Personnel Carrier and a Self-Propelled 155 mm Howitzer.

    Some are tracked vehicles and some roll on very big tires. The on-board diesel engine is used ONLY to charge the Lithium ion battery.pack. (Saft-France) The diesel motor is not connected to the drive train in any way.

    Electric hub motors propel the vehicle. This is not science fiction. These are not prototypes.

    These are front-line fighting vehicles, They are in production NOW and the Army will take delivery on the first of these, the Self-Propelled Howitzer, in 2008. MGVs are huge 20 ton behemoths and they are powered by ELECTRIC MOTORS..

    Welcome to the Electric Age.

    Please wake up. Stop arguing about bio-fuels and get with the program.



  33. “An anonymous poster said
    “batteries are “good enough”, in PHEV’s. Even lead-acid will do just fine in a PHEV: they’re cheaper than gasoline when gas hits $.175/gallon.” I don’t know where you are getting your numbers from…”

    That was me, and here are the numbers:

    Deep-cycle lead-acid batteries are commonly available for $65 per KWH, with lives of 400 cycles at roughly 80% depth of discharge. That gives a cost per KWH-discharge of $.20, and battery cost per mile of about $.05 (.25 kwh per mile for a mid-size sedan). Add electricity cost of about $.025 per mile (at the US average of $.10 per KWH), and your cost is about $.075 per mile, or about half of the average cost per mile for US ICE vehicles at $3.25 (the breakeven point is at about $1.75).

    The latest batteries are about 5-10 times more expensive, and have a cycle life that is 10+ times as long, giving roughly the same costs (keeping mind the time-value of money), but greater convenience, as the batteries don’t have to be changed during the life of the vehicle.

    Firefly looks very promising: it appears to be about 2 times more expensive, and have a cycle life that is 4 times as long, giving roughly half the cost, and intermediate convenience, as the batteries would probably be changed at least once during the life of the vehicle.

    Please note that I’m comparing to the US average fleet MPG. A Prius would have a higher transition point, but parallel hybrids are inherently more expensive to build than serial hybrids, so a PHEV provides a savings upfront. Smaller cars would too, but, they’re smaller…


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