'Eco-Friendly' Fuels That Waste Resources


A new study co-authored by Cornell ecologist David Pimentel concludes that turning biomass into liquid fuel consumes substantially more energy than the fuel generates. Producing ethanol from corn, for example, takes 29 percent more energy than you get by burning the ethanol. The study found that soybean-based biodiesel is similarly wasteful, while liquid fuels made from wood, switch grass, and sunflower plants are even worse.

Ron Bailey cited Pimentel's work in a 2003 Reason Online critique of ethanol subsidies.

[Thanks to Nicolas Martin for the link.]

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  1. Big fucking surprise. Does anybody really believe that ethanol is a good idea? Does anybody think it would even be used if it wasn’t for the corn lobby? I mean, high fructose corn syrup and ethanol are about the only way that they can steal any money because the farmers in developing countries would absolutely trounce the companies here.


  2. Thank Christ, if this leads to the end of those ceaseless, LONG “bio-Willie” commercials during the replays of the old Porter Wagoner and Wilburn Brothers shows on RFD TV.

    Thanks for preserving these old shows, Willie, but blow your fuel out your ass.

  3. Lowdog,

    Ethanol is a better fuel mix than MTBE.

  4. Wow, if it uses more energy than it generates, then that pretty much wipes it out as a fuel source, no matter how high the cost of oil becomes.

  5. Being an energy sink isn’t a disqualifying characteristic for transportation use – hydrogen is, too. (you can view ethanol as an energy storage mechanism just like hydrogen would theoretically be).

    That being said, ethanol is still stupid, if you have to use oil to grow the corn.

  6. Okay, by linking to Pimentel, you have implied an appeal to authority, expecting the readers to give extra weight to Pimentels proclamations, due to his ecologist background and expertise, which, surprise, congrue with your own re: ag subsidies and enviro-do-gooderism in general. Yet somehow, I doubt you and Ronald give any weight to Pimentels suggestions as to what we should do re: oil consumption, fossil fuel reliance, etc (as revealed in Ronalds subtle hint “and no friend of this author”). So, what are we the readers to think? Is Pimentel to be considered, or not? And if the answer is only on those small intersections of opinion with the Reason writers, than why link to him at all? Somebody’s cherry picking.

  7. from the article: In assessing inputs, the researchers considered such factors as the energy used in producing the crop (including production of pesticides and fertilizer, running farm machinery and irrigating, grinding and transporting the crop) and in fermenting/distilling the ethanol from the water mix.

    I haven’t read the actual full publication (although it’s printing now), but it seems first that some of the costs of the inputs are shared if the corn ears are harvested for food, and the remainder of the plant is used for generating the biofuel. shared use = shared costs = reduced cost for the fuel itself.

    further research might improve energy yields and efficiencies. this article (assuming its conclusions are accurate) just demonstrates that this process isn’t ready for widespread use yet.

  8. Can the scientists here tell me if it’s really even valid to compare various types of “energy”? Isn’t that more of an abstract concept than something specifically measurable? Wouldn’t you inevitably run into apples versus oranges problems? And even if there’s a standard measure of various types of “energy,” wouldn’t they still vary in terms of costs, making an economic comparison based purely on energy use and output meaningless?

  9. If only everyone would stop thinking of the general welfare, greater good, etc etc etc.

  10. During an Environmental Science (HA!) class in high school, we were all told the same thing, but that was with regard to the human food supply. That modern farming methods burned more calories of energy growing an acre of food than was actually harvested.

    This was all, of course, used as an example for why sub-Saharan African subsistence farmers who tilled the soil using human and animal power were so much more superior, morally and ecologically speaking.

    /no point, really

  11. Is Pimentel to be considered, or not?

    Don’t conflate a person’s scientific research with their policy prescriptions.

  12. Here’s the problem as I understand it:

    Any fuel processing method will yield less energy than was used in the process if all inputs are properly accounted for. That’s essentially the second law of thermodynamics: There is no 100% efficient process. (Yes, I know, the second law is a little more nuanced than that, but I’m giving the short version.)

    In producing biofuels, there are 2 types of energy inputs:

    1) Energy from the sun: Plants absorb sunlight and use that energy to synthesize water and CO2 into sugar. (Photosynthesis.)

    2) Fuel consumed by humans: Tractor fuel, fuel used converting ears of corn into, say, biodiesel, etc.

    The amount of usable energy that we’ll get from this process will inevitably be less than the total amount put in. But that’s OK if the amount that we get exceeds the energy burned by tractors, factories, etc. We burn some energy to harness solar energy (that’s ultimately what biofuels are, since you’re burning products produced by photosynthesis), and the amount of solar energy we get exceeds the amount we put in ourselves.

    If the amount of solar energy that we get is less than we spent, then it would have made more sense to leave the tractor in the barn, mothball the processing facility, and put that fuel into automobiles. Note that this observation has nothing to do with your stance on the environment, and is simply an observation that if the outputs provide less benefit than the inputs, well, maybe you shouldn’t have mucked around with processing the inputs.

    My understanding is that there are ways to make the processing more energy efficient (in a nutshell, ways to consume less energy while turning ears of corn into biodiesel or whatever). I’ve been told this by chemical engineers. Of course, saying that it’s possible is not the same as saying that it’s cheap or easy. I don’t know enough to comment on that.

    If the tractors can also be made more energy-efficient, then we’re on to something.

    I’ve also heard that hemp is ideally suited for this process, but I don’t know the details.

    In any case, those are the issues. As to solving them, well, that’s a whole other story.

  13. It’s not cherry-picking, it’s a “hey, this guy who has views we don’t normally agree with has come to an independent conclusion that this other idea, which you might assume he would agree with, is bullshit.”

    Maybe a little bit of schadenfreude, but that’s my take.

  14. Oh, apparently bacteria can turn food waste into methane. Although burning methane still produces CO2, if the methane was produced from plants (which took CO2 out of the atmosphere to make the plants) or animals (which ate plants that took CO2 out of the atmosphere) then the process isn’t adding any net CO2 to the atmosphere.

    (And yes, I know, some people here don’t believe that adding CO2 to the atmosphere is a bad thing.)

  15. Matt,

    An appeal to authority per se simply means he said it, so it’s true and/or correct. Pimental conducted a study to reach his conclusion, so this blog post amounts to an appeal to the skills and integrity Pimental employed in this particular study. It doesn’t imply he’s intrinsically right about anything and everything. Still, it obviously begs the question of whether there are other equally well regarded studies that have drawn other conclusions? Or, as mediageek’s post would imply (his disavowal of any point notwithstanding), can such studies really be trusted at all?

  16. fyodor:

    no, you really can measure energy directly, but the article’s attempts to measure the costs of producing the energy can be questioned.

    think of food calories. a calorie is a measure of energy (actually, each food calorie is really 1000 calories, or 1 kilocalorie), 1 calorie (not food calorie) is the amount of heat required to raise the temperature of one gram of water by one degree Celsius (temperature is a measure of heat energy, the average kinetic energy of the particles of a system). one calorie is equal to about 4.19 Joules (the metric unit of energy)

    there is also the question of the efficiency of energy conversion, but I’ll leave that explanation to a physicist (thoreau?)

    if I got anything not quite right here, then dammit Jim, I’m a biologist, not a physicist!

  17. I’m not sure if this post was aimed more at dismissing alternative-fuel technology or ag subsidies.

    And joe’s right about MTBE, if I may appeal to the authority of Wikipedia:

    “The clean-up of all MTBE in the U.S. is estimated to cost as much as $140 billion, including breaking down the compound in municipal water supplies and repairing leaky underground oil tanks. Much of the controversy centers around who will have to pay the costs of this clean-up, if such a task is required.

    Recent state laws have been passed to ban MTBE in certain areas. As of 2004, more than half of all states still permit its use. However, the states of California and New York, which together accounted for 40% of U.S. MTBE consumption, banned the chemical starting January 1, 2004. (A table of state by state information is available here at the Department of Energy website.)

    In 2000, the EPA drafted plans to phase out the use of MTBE nationwide over four years. Upon taking office, the Bush administration cancelled those plans.

    In April of 2002, a California jury found several oil companies guilty of irresponsibly manufacturing and distributing MTBE, stating that the companies acted with malice in failing to warn customers about the dangers of MTBE contamination. There are hundreds of other lawsuits currently active regarding the compound.

    Between 2000 and 2004, the top three MTBE manufacturers have donated over $1 million to the United States Republican Party and key members. An amendment to provide blanket immunity from MTBE-related lawsuits was inserted into the House version of the 2003 Energy Bill. The bill failed to pass when six Republicans voted against it, mostly because of that amendment. MTBE lawsuit immunity is likely to remain a political issue in the years to come.

    The Energy Policy Act of 2005, passed on April 21, 2005, shields MTBE manufacturers from water contamination lawsuits, which means that all cost for the 80 lawsuits filed so far will be paid by the taxpayer. This provision has been a top priority of Tom DeLay and Rep. Joe Barton, chairman of the Energy and Commerce Committee. [2] This bill also includes a provision that gives MTBE makers, including some of the biggest oil companies, $2 billion in transition assistance as MTBE is phased out over the next nine years. [3] The New York Times calls this ‘A Dirty Little Footnote to the Energy Bill.'”

    The lesson, as always: Tom DeLay is an asshole.

  18. thoreau: I think you’re confusing two different issues. I think you can get more energy out of fossil fuels that you invest in extracting the fossil fuels, you just can’t get 100% of the potential energy out of the fuels, because during the conversion from chemical energy to heat energy, some of the heat energy is lost. We can blame the 2nd law of thermodynamics for this.

    if energy extraction took more energy than the energy extracted, we’d never be able to use fossil fuels for anything other than extracting fossil fuels.

  19. The issue here is called Energy Return On Investment (EROI).

    Currently in the United States, for every one barrel the oil companies use to get oil out of the ground, we get back 3 barrels in return. This is a positive EROI. When we were first drilling for oil, the ratio was more like 100:1.

    The Cornell study finds that in order to get one barrel of oil equivelent energy out of corn-based ethanol production, we have to expend 1.3 barrels of real oil. This is a negative EROI and unsustainable in the long term. We’d just end up using oil faster in order to use this stuff as an alternative fuel.

  20. >>>Don’t conflate a person’s scientific research with their policy prescriptions.

    Uh, Im not, Im asking if I should consider Pimentels other scientific research to inform my opinions on various policy prescriptions which my run counter to the Free Markets Maxim heralded on these pages. Jacob has asked us to consider Pimentel re: ethanol fuel not because of energy ineffeciencies so much as this undermines ag subsidies (fine by me). But when Pimentels research may lead one to conclude that anti-free market enviro policies might be the best way, I doubt we’ll be reading them in these pages.

  21. Energy conversion never destroys energy, but it doesn’t always produce useful energy. Some of it escapes as heat. And you can sometimes harness waste heat, but that process would also produce waste heat. There are limits. In order to really use heat you have to get it to flow. In order to get heat to flow, you need to have a colder region. And it all gets complicated and Carnot engines aren’t really my thing. But suffice it to say that energy is converted all the time. For instance, say that somebody eats an apple and then rides a bike, and you use a heat sensing camera to look for frictional heating in the bike:

    Sunlight -> Chemical bonds in sugar -> Some other chemicals (sorry, not much of a biophysicist yet) -> Contractions of muscle -> Motion of bicycle pedals -> Kinetic energy of bike -> Heat in ground (friction) -> Infrared light -> Electrical currents in heat-sensing camera.

    Pretty amazing, huh?

    None of those steps were 100% efficient, in every step some energy either wasn’t converted or was converted to heat. And even with the heat, not all of it was picked up by the camera. And of the heat picked up by the camera, not all of it went into producing electrical current that forms an image. Some of it heated up the camera itself.

  22. Would the production of ethanol ever reach a point where we could produce enough to begin using as an independent source to produce more, or is it just a dog chasing its tail?

    If ethanol technology’s a bust, then the industry should immediate look into new alternatives, and not waste any more taxpayer money. IF it’s a bust — and I don’t know yet if it is. But wouldn’t increasing energy efficiency with existing fuels, and the engines that burn them, create the same reduction in pollution that biofuels would supposedly produce?

  23. biologist-

    I think we’re cross-posting here, but I get your point. I don’t think I’m communicating very clearly today.

    I realize that every energy extraction process burns energy, and that no fuel burns with 100% efficiency. My point was that for some processes, the total amount of energy that you get from (inefficiently) burning a gallon of fuel is less than the energy that it took to process that gallon of fuel. (e.g. getting oil out of the ground and turning it into gasoline)

    But there could be a process that burned so much fuel to produce one gallon that you actually got less out of the final gallon. Supposedly the current methods for making biofuels are in that category.

    Anyway, I didn’t mean to imply that fossil fuels were in that category.

  24. Okay, it’s Monday–I’m not thinking clearly. If the cost of oil gets high enough, even ethanol could be ‘cost-effective’. The question being, how high does oil have to get?

  25. Point of clarification: I meant that for every 100 barrels we got out of the ground, the oil companies only had to expend one barrel earlier last century.

  26. Oh, to further elaborate on fyodor’s question about whether comparing types of energy is an apples-to-orange thing, consider this:

    To produce that sunlight, deep in the core of the sun hydrogen nuclei fused into helium nuclei that are lighter than the original hydrogen nuclei. The mass discrepancy produced gamma rays by E=mc^2. Those gamma rays heat electrons and protons in outer layers of the star, which re-radiate the energy as visible, IR, and UV light (well, other forms of light too, but those are the types most commonly harnessed). That light travels across space before being absorbed in a plant.

    And that fusion reaction was made possible by the high kinetic energy of the protons, which enabled them to come together despite strong repulsive forces. The kinetic energy came from heating that occured when the gas inside the star was compressed by gravitational forces.

    The universe is an amazing place, with energy constantly being converted from one form to another.

  27. thoreau: we’re on the same page now

    Michael A Clem: no matter how cheap it gets relative to oil, if the energy efficiencies are negative, it won’t work, JonBuck explained above. also, thoreau’s 2:48 post works as an explanation also.

    SPD: possible, a friend of my did his PhD on genetically manipulating E. coli bacteria to force more of its metabolism to produce ethanol than other possible byproducts, and to be able to digest cellulose, cellobiose, lignin, and just more of the organics in the plant material in general.

    we also need bacteria to be able to withstand a higher ethanol concentration before they die.

  28. Again, though, even with the energy budget as described by various people, there still may be advantages in ethanol production in PORTABILITY and STORAGE.

    Of course, NOT if we use gasoline for the energy input.

    But if we harvested the corn using electric threshers which were charged when not in use by wind turbines, for instance, the ethanol production would be a good process IF it was still more feasible to drive automobiles with ethanol than with batteries, for instance.

    (you could take this all the way back to coal – we can’t feasibly run our cars on coal, but presumably you could run a huge harvester on it much more effectively…)

  29. we also need bacteria to be able to withstand a higher ethanol concentration before they die

    Well, I know that the human body has a lot of bacteria in the digestive tract. And I know that your typical Irish digestive tract has a lot of ethanol in it. So why not just culture the bacteria from an Irishman’s digestive tract?

  30. another important point if this ever becomes energy and cost efficient enough is that it results in no net carbon dioxide inputs into the atmosphere, which will also save a lot of paper being used to argue whether that matters or not.

  31. no matter how cheap it gets relative to oil, if the energy efficiencies are negative, it won’t work

    One way to understand this point is to consider that the cost of this process depends in part on the cost of the energy inputs. If we do this process with oil, the more expensive the oil gets the more expensive the biodiesel gets. And if we do it with biodiesel instead of oil, we avoid the oil cost but the process becomes a snake eating its own tail and it never produces anything.

    Bottom line is that negative energy efficiency will never be cost effective. It can still be done if you get your energy from some other source, but the process will always cost more than whatever your other energy source is. If you have to consume, say, 4 units of oil/sun/wind/hydro/nuclear/whatever to get as much usable energy as you’d get from 3 units of oil/sun/wind/hydro/nuclear/whatever, it would have been cheaper to just buy 3 units of oil/sun/wind/hydro/nuclear/whatever.

  32. “So why not just culture the bacteria from an Irishman’s digestive tract?”

    Hey, I resemble that comment! I fart in your general direction.

    Sorry, thoreau… we Irish are still a bit wary about having our bodies harvested for public consumption. A Modest Proposal, indeed, sir! 🙂

  33. Biologist: I have high hopes for using gentically engeered organisms for these uses.

    On another front, there’s also Thermal Depolymerization (TDP). This process mimics geology and can turn many forms of organic matter into oil. Even stuff like sewage.


    Unfortunately there’s a grand total of one pilot plant in the U.S. It’s currently making oil from turkey guts.

    I’m not sure what the EROI would be. There hasn’t been a study done yet. However, it’s more efficient than ethanol production in terms of output efficiency, which means it may end up with a positive EROI. I see this process using waste products as a supplement to oil supplies, until we can get those aforementioned genetically engineered organisms specifically for this process.

    It’s a pity Changing World Technologies is a private company, else I’d invest.

  34. “I’ve also heard that hemp is ideally suited for this process, but I don’t know the details.”

    Yes, people who consume hemp generally use less energy, unless there is a bag of Cheetos nearby. Science needs to determine just how far way the bag of Cheetos can be placed to get the hemp user to expend energy to obtain it, then harness that somehow.

  35. We could place the stoner on a hamster wheel with the Cheetos just out of reach.

    joe once admitted that he has a Baptist minister on a hamster wheel in his basement, providing electricity for his house.

  36. JonBuck,

    I remember reading that “turkey guts” biomass article in Scientific American. Once I finished retching, I considered that this might prove to be an interesting alternative fuel source. Maybe it wouldn’t become prevalent everywhere, but a cheap and plentiful source of energy is a cheap and plentiful source of energy. I think.

  37. joe once admitted that he has a Baptist minister on a hamster wheel in his basement, providing electricity for his house.

    I read somewhere that in Central City, the Flash had been strapped to a turbine and forced to run endlessly as a cheap source of power. Could be a rumor, so please, by no means appeal to my authority!

  38. “joe once admitted that he has a Baptist minister on a hamster wheel in his basement, providing electricity for his house.”

    I recently mounted a feeding tube a couple feet beyond his reach, and I’m actually selling energy back to the grid.

  39. SPD: I look at the process as a way to extract as much energy out of a production process as possible, even if that process is not intended for creating energy. For instance, I read somewhere that recycling plastic isn’t really economical. TDP could make it both economical and energy-efficient. And they can get more oil (70% yeild from that feedstock) out of plastic than out of most anything. And consider the millions and millions of tires just sitting in landfills.

    I also wonder if you could use this process for refining tar sands and oil shale.

  40. joe, didn’t you know that it’s murder to deprive him of a feeding tube?

  41. If most of the machines in use today were as fuel-inefficient as those of a century ago, I’d be much more inclined to hit the environmental “panic button” than I am now.

  42. Oh no, thoreau, I feed the whole family. Gotta keep ’em going. Lotsa carbs.

    They just get all hyper whenever they see a disconnected feeding tube. They start squaking and bolting at it. Really keeps the wheel spinning.

  43. If you have to consume, say, 4 units of oil/sun/wind/hydro/nuclear/whatever to get as much usable energy as you’d get from 3 units of oil/sun/wind/hydro/nuclear/whatever, it would have been cheaper to just buy 3 units of oil/sun/wind/hydro/nuclear/whatever.

    True. But if oil prices have soared into the stratosphere, it might still make economic sense to produce ethanol under these circumstances provided that the primary power source used to produce it is something other than oil. At least unless you can put a nuclear reactor or a wind turbine inside of a car.

    Also, I think gasoline taxes have to be factored into any study comparing the costs of ethanol and gasoline. Given that its raw material doesn’t have to be imported from shady, unstable locales (Louisiana notwithstanding), Congress might decide to keep sales taxes on the product at a minimum, thereby tilting the cost balance in its favor.

    Lastly, I don’t know if Jacob’s seen it, but another study on the efficiency of ethanol production turned up very different figures:

    In the United States, ethanol yielded only about 10 percent more energy than was required to produce it; in Brazil, where a different process is used, ethanol yielded 3.7 times more energy than was used to produce it.

    I sometimes get the impression that Reason allows its politics (which I largely agree with, btw) to affect the objectivity of its reporting on science-related developments. If a fuel source happens to be subsidized by the government, it’s likely to be the subject of a post questioning the fuel’s viability. If those worried about changes in the Earth’s climate favor heavy-handed state intervention to rectify the problem, then you’re likely to see a column questioning the existence of the changes.

  44. I was gonna bring up thermal deploymerization, too. Seems neat.

    There’s plenty of energy available and flowing through the economy. Most of it seems to escape (or is discarded) because it is today cheaper to use yesterday’s stored energy. In the long view, we’ll be all right.

  45. True. But if oil prices have soared into the stratosphere, it might still make economic sense to produce ethanol under these circumstances provided that the primary power source used to produce it is something other than oil. At least unless you can put a nuclear reactor or a wind turbine inside of a car.

    Good point. I guess it depends on where the fuel input comes from. If most of the energy used to make ethanol (be it for tractors or reactors or whatnot) comes from fossil fuels then ethanol will never be competitive. But if the processing plant ran on solar power and the tractor had batteries charged with wind or solar power then the situation changes considerably.

    If somebody produces a cheap solar-powered tractor and all-solar processing plant that converts corn into fuel, no doubt the Senate will react to this crisis by creating some regulation that renders the system uneconomical and in need of subsidy once more!

  46. Since I grew up on a farm I have to giggle at the concept of the solar/wind powered-tractor and “thresher” (lol, that’s what they called them 70 years ago, unless that’s American lingo.)

    The peak output of typical solar cells is about 100 watts/square meter for maybe a few hours a day, then cut that in half by the time you get it into and out of a battery. Modern combine harvesters have at LEAST 300hp–and would be putting out a significant portion of that all the time–which translates to about 223Kw and could be used for a couple hundred hours or more a season. So to run the thing for a season would take, crudely guesstimating here, around 3 months of charging even with over an acre of solar cells, which would cost six figures.

    Even with some more practical form of power generation, and if you don’t need as much power since electric motors put out more torque, it’s still bonkers because of the batteries. The capacity needed for one 12 hour shift(and these things are kept running near 24/7 when in season) could easily fill a(diesel)semi truck, then you’d need very powerful equipment for swapping them out every hour or two. This is compared to burning 4-6 gallons of diesel per hour.

  47. “The study found that soybean-based biodiesel is similarly wasteful,…”

    The National Renewable Energy Laboratory begs to differ:


    From page v (Roman numeral 5) of that report:

    “Substituting 100% biodiesel (B100) for petroleum diesel in buses reduces the life cycle consumption of petroleum by 95%.”


    Someone whose opinion I respect very much says that David Pimentel is way off, concerning biodiesel. (I won’t quote him, but his actual statement was considerably stronger.)

    I need to do some more research (I haven’t even read through the NREL report very carefully), but based on this person’s opinion, I’d definitely be very sceptical concerning David Pimentel’s findings.

    Mark Bahner (environmental engineer)

  48. Joe:

    You couldn’t be wronger about ethanol versus MTBE.

    The reasons are too numerous to cite.

  49. Mark:

    The Cornell study takes into account the total useage of all petroleum-based products in the production of soybean-based biodiesal. Was this methodology flawed?

    Again, the issue here is Energy Return on Investment.

  50. The comments about “energy returns” are pointless. What matters is financial returns. If the value of the input energy (plus the value of all the other inputs) is lower than the value of the output energy, then it is profitable, and somebody will be willing to operate the process. We value transportation energy much higher than “static” energy (i.e., electricity), so any process that can transform static energy into transportation energy is going to be a winner, even if it uses a lot of input energy.

    The problem with ethanol is that many of the energy inputs are from transport energy. So you’re using 1.3 amounts of valuable energy to make 1 unit of energy of the same value. If you could use coal and solar and hydro to make ethanol, it would make sense. But you have to use crude oil, so it doesn’t.

    Maybe one day ethanol production technology will allow ethanol to be competitive with crude-oil based fuels, but as of right now, it needs massive subsidies to be competitive.

  51. Barry:

    For the most part, energy and financial returns go together. Both must be positive in order for the resource to be viable.

  52. fyodor

    In principle, any form of energy is convertable to any other form of energy. The conversions are mathematically precise. I used to work for a gas & electric company in a past career.

    Thoroeu and biologist are trying to say the problem is, the conversion process in the real world may be highly inefficient. You always loose energy when you convert it to another form.

    Biologist is right. The problem isn’t in converting energy, we can readily get around the apples to oranges problem. The problem is in the economic projections.

    It would seem that we usually can’t predict the true cost of a bridge with good accuracy. When you start adding complicated things like energy conversion processes (combustion, electro-chemical conversion, mechanical energy, etc, etc) our predictive powers would seem to nose dive.

    Financial return really is “the bottom line”. And if you can figure out how to predict it, then you should get rich quick. You’ll be the first have mastered the stock market.


    If ethanol technology’s a bust, then the industry should immediate look into new alternatives, and not waste any more taxpayer money.

    You clearly do not understand the purpose of lobbying your congressman. Get a grip!

  53. I’d be interested in a similar input-output analysis of nuclear power–not only in terms of whether it’s an energy sink, but of the state subsidies needed to make it artificially profitable. That includes state R&D funding, state assistance to build roads to the uranium mines on state land, state subsidies to the disposal of waste, state subsidies to decommissioning cost, the Price-Anderson Act–the whole shebang.

  54. JonBuck writes, “The Cornell study takes into account the total useage of all petroleum-based products in the production of soybean-based biodiesal. Was this methodology flawed?”

    That’s the fundamental idea of a “life cycle” analysis. One takes into account not just the impacts of turning the soybeans into biodiesel, but also the impacts of growing the fuel. (And the impacts from disposing of the wastes at all stages, and the impacts from burning the two fuels.)

    But the National Renewable Energy Laboratory (NREL) study IS a life cycle inventory. And it gets fundamentally different results from David Pimentel’s reported results. Once again, from page v (Roman numeral 5) of the NREL study:

    “Substituting 100% biodiesel (B100) for petroleum diesel in buses reduces the life cycle consumption of petroleum by 95%.”

    JonBuck continues, “Again, the issue here is Energy Return on Investment.”

    Yes, and the NREL study gets fundamentally different results from Pimentel’s study. This is what the NREL study concludes (also on page v):

    “Biodiesel yields 3.2 units of fuel product energy for every unit of fossil energy consumed in its life cycle.”


    Someone is wrong. And by the reaction of my co-worker, I suspect it’s Pimentel, not NREL.

    Mark Bahner

    P.S. I can’t even find the part of Pimentel’s study that deals with biodiesel. Can anyone find that part of the Pimentel’s study that deals with biodiesel? (I don’t mean the summary of results…I mean the actual study, including how the biodiesel numbers were calculated.)

  55. Mark:

    I have the full article of Pimentel’s study right here. The full cite is: Natural Resource Research. Vol. 14, No. 1, March 2005, 65-76. The biodiesel section starts on page 71.

  56. “The full cite is: Natural Resource Research. Vol. 14, No. 1, March 2005, 65-76. The biodiesel section starts on page 71.”

    OK, I downloaded a free copy. (I definitely wasn’t going to pay $40 for something I’ve been told is deeply flawed.)

    I can see that Pimental and Patzek include at least one blatant misrepresentation. See page 72, right-hand column, 2nd-to-last paragraph before “Sunflower Conversion to Biodiesel.”

    Pimentel and Patzek write, “Sheehan and others (1998, p. 13) of the Department of Energy also report a negative energy return in the conversion of soybeans to biodiesel. They report ‘1 MJ of biodiesel requires an input of 1.24 MJ of primary energy.'”

    Therefore Pimentel and Patzek are representing that “Sheehan and others of the Department of Energy” AGREE with Pimentel and Patzek. But “Sheehan and others” are the folks at ****NREL.**** The 1998 report is simply an earlier version of the one I’ve already linked to. See this website for the 1998 report:


    The report makes it *very* clear (see page 13) that the input of 1.24 MJ of primary energy is almost entirely ***solar*** energy.

    And the report makes it VERY clear (see Table 6 on page 15) that there is only 0.3110 MJ of fossil energy input per MJ of biodiesel output.

    So the Pimentel and Patzek statement is a blatant misrepresentation. The question is, was it made merely out of astounding incompetence, or was it a deliberate misrepresentation (i.e., a lie)?

    I simply don’t see how Pimentel and Patzek could be so incompetent as to unintentionally misrepresent a major study that clearly conflicts with their own. So my guess is that the misrepresentation was deliberate.

    That’s really pathetic. I hope someone points out the misrepresentation to the readers of Natural Resource Research.

    The NREL report absolutely does NOT agree with Pimentel and Patzek! Pimentel and Patzek say that producing biodiesel from

  57. Oops. I cut/pasted stuff for that last comment. The final sentence-and-a-half should have been deleted.

  58. Mark,

    Don’t count on it being pointed out publically.

    When I first saw Ron’s article I thought “is there anybody left who doesn’t know the answer to this one?” This goes back to at least the 1970’s, when Barry Commoner wanted to be president. But clearly, many still don’t know.

    Until somebody figures out how to up the corn yield per acre big time, with little additional energy input, using corn for fuel isn’t going to make sense.

    Energy analysis in the scientific literature at large is frequently not objective. There are too many environmental tie-ins, so everybody’s religion gets involved.

    Solar energy was going to save the world — until somebody pointed out, a second law analysis shows that a large fraction of the solar energy that arrives at the earth’s surface is at too low a level to do any useful work.

    There are things you can do with solar — if the sun’s out — but it’s a diffuse source of energy and it’ll never do all the things it’s been touted as being capable of.


    I’d be interested in a similar input-output analysis of nuclear power

    Well……if you look at coal fired plants today from the same angle, I wouldn’t bet too much that nukes aren’t competitive after all. But it’s been a lot of years since I worked in the electricity generating business.

    I can tell you this, though. We had a nuke plant, as well as coal and oil, and even an old gas fired plant (now moth balled). Given a choice between living next door to the nuke, vs either the coal or oil fired plants, I’d live next to the nuke any day. The radioactive fall out level around oil, and especially coal, is gigantic compared to what’s allowed for a nuke plant.

    Now, if We the People were capable of being rational about how we dealt with such things, there are ways of dealing with nuclear waste products. Think of it this way — with a nuke plant I get a little bit of really toxic waste, whereas with a coal plant I get a whole lot of lesser but still pretty darned toxic waste.

    Which is really more expensive to contain in the long run? The answer might surprise a lot of people.

    Natural gas is the cleanest burning of the bunch, but it’s also inherently less efficient.

    If we were smart, most cities in the US would be running co-gen plants that burn garbage. But We the People are not capable of assessing such options rationally anymore……

  59. As a final word, here’s a Wikipedia article on biodiesel:


    Most interesting they note is a species of algae that could theoretically produce 10,000-20,000 gallons *per acre* per year instead of the paltry 50 gallons that soybeans produce. Now there’s an EROI for you.

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