3 things you need to know about biofuels

Why care about liquid fuel?

There’s a reason we use different forms of energy to do different jobs, and it’s not because we’re all just that fickle. Instead, we’ve made these decisions based on some combination of what has (historically, anyway) given us the best results, what is safest, what is most efficient, and what costs us the least money.

In a nutshell, that’s why liquid fuel is so valuable. So far, it’s the clear winner when we need energy for transportation—especially air transportation and heavy, long-distance shipping—because it allows you to stuff a lot of energy into relatively small amount of storage space, and easily refill on the go. There are other options, of course, like electricity. And that can work quite well, depending on what you’re trying to do. Eventually, we may find ourselves in a world where liquid fuel is no longer the best option. But we aren’t there yet. And for those forms of transport that take us into the air or move our belongings very long distances, we aren't likely to get there for a good long time.

That's why I care about liquid fuel, and why I'm interested in the future of biofuels. Yes, biofuels do have a future. But what that future will be depends on whether we can control for some very messy variables. Here, in three points, are the big things you need to know about biofuel.

1. Corn ethanol really is flawed. But maybe not as much as you think.

Biofuel is a nice, round word encompassing a lot of tricky, little, oddly shaped dots. You can make biofuel from lots of different things, in lots of different ways. Corn ethanol, cellulosic ethanol, bio-oil, bio-diesel, algae oil—they all have some benefits and some detriments, which means they all have some big backers and some big haters. Right now, any biofuel produced at a big, commercially useful scale is bound to be ethanol, and in the United Sates, that means corn ethanol. But, from what I see, the evidence favors using options that aren’t dependent on a dedicated corn crop. That’s not to say that corn ethanol is the devil—its bad reputation comes, at least in part, from backlash against some pretty heinous overselling—but it does have some big drawbacks and we might have an easier time making truly Green biofuels another way.

Part of this stems from corn’s big appetite for inputs, like fertilizer. Those inputs represent energy spent, and energy spent is (in today’s world) greenhouse gas emissions produced. The more energy you have to spend on producing a biofuel—from making fertilizer and running the tractor for annual replanting, to powering the fuel production process and shipping fuel to the gas station—the less benefit you actually end up with at the end. There are lots of different ways to tally those numbers up, but Argonne National Laboratory has one of the best calculators around. Called GREET—a perky, welcoming acronym for The Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation Model—it’s a software program that adds up all the different ways energy is used and greenhouse gases are emitted over the life of a fuel, and runs simulations based on variables like geographic location, types of farming methods, and types of fuel production methods.

GREET figures that corn ethanol really can be better than gasoline. You can get more energy out of a gallon of corn ethanol than you used to make it. And a gallon of corn ethanol can reduce greenhouse gas emissions by somewhere between 18% and 28%, compared to a gallon of gasoline.

But here comes our friend, the yesbut. Yes, you can get an emissions benefit from corn ethanol. But, this only works if the ethanol plant is powered by natural gas. If it runs on coal, you’re not reducing emissions at all.

Also: The picture only looks this rosy when you compare corn ethanol to gasoline, but not to any of the other competing biofuels. A 28% reduction in greenhouse gas emissions sounds fabulous, until you look at cellulosic biofuels—made from things like grass, stems, wood chips, and trash paper. There’s lots of different ways to make cellulosic biofuels, including a cellulosic version of ethanol, and they reduce emissions by a whopping 82%-to-87%. Nobody is producing them at scale yet, but in a world of limited time and resources, cellulosic biofuels look like a better bang for our buck. Plus, you get some ancillary benefits from the plants that make cellulosics that corn can't match, including improvements to soil quality, and reduction of erosion.

2. We can screw up cellulosic biofuel, too.

It’s important that I don’t give cellulosic biofuels the used-car lot megaphone treatment that corn ethanol received. They’re better, not perfect, and a lot of the research being done on cellulosic biofuels is focused on figuring out how to not screw them up. They could still backfire spectacularly—driving up food prices, dumping more fertilizer into the Mississippi, or even increasing the amount of carbon dioxide in the atmosphere. To keep that from happening, scientists say we have to pay a lot of attention to what’s being grown, and where.

For instance, in the Midwest, it’s likely the best biofuel crop won’t be a single crop at all. David Tilman, an ecologist at the University of Minnesota and winner of the 2008 International Prize for Biology, has been studying prairie plant biofuels for more than a decade.

Out on the prairie, Tilman and his team found significant problems with growing a field of nothing but switch grass. By its lonesome, the grass grows in the sickly, patchy style of a 15-year-old’s goatee—creating a temptation to douse it in fertilizer. After seven years, Tilman said, it usually needs to be plowed under and planted again. But when the team planted a mix of four native grasses and four native legumes—think alfalfa or clover—the results were very different. Together, the plants grew in a thick mass and didn’t need to be re-seeded or fertilized. After 10 years, Tilman found these mixtures were producing 238 percent more energy, every year, than any one plant grown alone. They also made the soil more fertile, naturally increasing levels of nitrogen and phosphorous. “It makes sense,” Tilman said. “It’s a mixture of prairie plants that made that soil to begin with.”

But even the most well-meaning, soil-enriching mix of plants has to deal with the problem of land-use change.

3. Land use matters. But there's still a lot we don't know about that.

Direct land-use change is easy to wrap one’s head around. Say you own an acre of timber and you decide to clear it, because you can get a good price for growing biofuel crops there, instead. That timber was locking in a lot of carbon in the form of trees, and plants, and virgin soil. Depending on what happens to the trees, and how you treat that soil, you can end up inadvertently releasing a lot of carbon dioxide into the atmosphere. Enough to affect the net emissions of the biofuel crop you grow there later.

Indirect land-use change is a little more thorny. The world, as they say, is flat. An acre of corn or wheat grown in the United States isn’t merely used to fatten American cattle or bake American bread. We participate in a global food market and what we do here has consequences abroad. So, if a farmer in the Midwest decides that she’s going to take an acre of corn and replant it with a prairie grass and legume mix for biofuel, what happens?

Some experts are worried it would lead to an decrease in availability of corn, which would lead to a rise in the price of corn, and a farmer in some other part of the world, or even just another part of the U.S., deciding that he’s going to capture that cash benefit by taking an acre of timber and turning it into an acre of corn. Or, just as bad, that the price increase would lead someone, somewhere, to go hungry.

At first glance, that logic sounds foolproof. And most researchers agree that it has to be taken into account and studied as we plan the future of energy. But, when you ask how big an impact land—use change might have—that’s when the experts start to disagree.

There are some researchers who think land-use change basically negates the usefulness of all but a tiny portion of biofuels that come from certain farm, industrial, and municipal wastes. There are others who think that it won’t really be a problem. Based on the majority of scientists I've spoken with and the research I've read, I think the reality lies somewhere in between, and that there’s a good chance cellulosic fuels can skirt the issue if they’re done the way people like David Tilman have proposed.

At the heart of this debate: How well the computer models used to predict land-use change reflect reality. A model is only as accurate as the assumptions that go into it, and critics say that the worst-case-scenarios are based on some pretty faulty assumptions. First, there’s the assumption that increased demand for a crop like corn will inevitably lead to deforestation, or plowing under previously wild land. But in the United States, as well as overseas, there’s a surprising amount of previously cleared land that isn’t being used to grow much of anything, either because farmers have been paid a subsidy to leave it fallow, or because the land turned out to be no good for annual row crops, or, as is common in developing countries like Brazil, because cleared land is owned land—even if you’re just keeping one cow on it.

“We’re only using between half and a fourth of all previously cleared forest land on Earth for crop production in any given year,” says Keith Kline, a global change and developing countries analyst with the Oak Ridge National Laboratory.

Kline, who worked in developing countries for 22 years studying and promoting biodiversity, is one of several scientists I spoke with who said that—contrary to some land-use change models—deforestation is not about crop prices. At least, not solely. Social and cultural factors—like the desire to own land you can get for free just by clearing it—are equally important. You can’t assume that a rise in global crop prices will naturally lead to an increase in deforestation, or that deforestation would stop if crop prices stayed the same or went down. In fact, according to Kline, the highest rates of deforestation worldwide happened in the 1990s, before the ethanol boom in the U.S. and at a time when food commodity prices were consistently low. And deforestation rates have been falling ever since.

The second bad assumption the worst-case models make is that the same amount of land can’t grow more crops. Perennial mixes for cellulosic biofuels could actually be grown alongside row crops, or on the same land, between the harvest and next planting, Tilman told me. At the same time, crop yields—the amount of useable stuff you can grow without increasing the square footage—have consistently gone up, every year, in the United States. That happens in small increments today, but there’s plenty of room for yields to improve dramatically overseas. The productivity of what you do with the crops can also increase. For instance, most corn is actually used for feeding livestock, not people. But less corn being available doesn’t necessarily mean people eat less meat. Instead, they might just switch the kind of meat they eat. It takes about 10x as much corn to grow a pound of beef as it takes to grow a pound of chicken.

Finally, some predictions in the worst-case models don’t match up with what we’ve seen in the real-world. They assume corn exports will go down, as U.S. ethanol production rises, leading to those higher global prices that theoretically inspire deforestation to begin with. But that’s not what happened. Instead, in 2007, as corn ethanol production in America hit 6 billion gallons, corn exports rose by 14 percent, compared to the previous year. In fact, they’ve been, generally, trending on the rise since 2003.

Image: Cornfield, a Creative Commons Attribution No-Derivative-Works (2.0) image from der_bauer's photostream



  1. The simplest way to think about biofuels is to look at their Caloric* content, making it possible to imagine them as human food (which they could be, with slightly different processing).

    US liquid fuel use is equivalent to the ENTIRE WORLD’S Caloric intake. It is simply not possible to produce petroleum-scale amounts of biofuels. Biofuels are only a fractional part of a future that must include drastically reduced energy use.

    See http://cascadiacarbon.org/blog/?p=77 for more.

    *To convert to kilojoules, multiply by 4.2.


    *$50,000 from the Texas Hemp Campaign (America) for anyone who can disprove the claims made within the book* http://www.jackherer.com/thebook/

      1. First it was all caps, now all lower-case with broken sentences? Seriously, starting to think this *is* a spammer.

    1. InterestShack, could you stop treating this thread like a highway to post billboards along? I’m sure many people here are sympathetic to your views, but respond better to conversation than to cut-and-pasted ad copy. 

    2. For all I know you may have an excellent point, but I’ll be damned if I give it any consideration when presented in ALL CAPS YELLING that sounds suspiciously like spam.

  3. nicely written, rounded, balanced, piece.  and i think i learned something today.  thanks mkb.

  4. Using corn for biofuels has the added drawback of causing people and vehicles to compete for food. Increased corn prices might not bother you very much, but in a lot of south and central america corn is a staple.

    Grasses/etc. also have the added benefit that they can be easily grown in many conditions where corn is not viable as a food crop. 

    1. I think it won’t be a tragedy if the US no longer overproduces its corn. It will give other countries like Mexico a chance to sell their corn in other markets. Currently we import it because US corn is cheaper! But that’s only because it’s subsidized! It’s fake! Foreign markets would benefit ultimately from the US actually using up its corn product.

    2. one other good point about grasses – is that they are perennials and there is no need to till and replant them and when they are cut down or for that matter eaten by cows there is a built in tendency for the organism to maintain a balance below ground so the root system sloughs off and equivalent amount of biomass as was removed from the top.  This is essentially a form of carbon sequestration and it improves the soil while producing beef, chicken etc. 

       See Joel Salutin from Polyface farms – he is an activist -beyond organic farmer. He raises cattle, chickens and pigs and considers himself a ‘grass farmer’.  He has a system that tries to match what goes on in the natural world – first cattle graze a section of grass land for a few days and leave droppings.  Then using a mobile electric fence he moves them over to another section and brings in his chickens which feed on the larvae that are just about to hatch from the droppings. The chickens are also given feed , but they are also moved on after some time. 
      there is  much more to this system of farming, but his 300 acres supports around 9 people including family and outside workers.  His beef and chicken are much sought after but the important point is that if all cattle were raised this way in North America the grass sequestration method would offset the extra co2 in the atmosphere in about 30 years.

  5. Feedlot soil is over-fertilized and contaminated by excessive collection of animal droppings containing antibiotics, etc., so it’s unsuable to grow food crops even for cattle. But what if the pens (which are huge) were rotated with biofuel crops? Could that increase profit for farmers without constantly polluting the soil? Could such crops be grown in these areas without adding fertilizers? Could the use of land in this way actually be bettered by a reduction in the concentration of animals on the land? Might it be possible to improve animal living conditions while increasing profit to farmers, decreasing fuel costs, restoring soil and decreasing overall pollution?

  6. I don’t think bio-fuel will be the next big thing; there are a lot of countries that do not overproduce their produce (ha!) in such an extreme manner as to make it profitable.
    Nonetheless, here’s something we have a lot of: trash. If we can turn trash into fuel, no one will dispute better things will come of it; landfill sizes will decrease, and the carbon burnt from any biomass is essentially carbon that was going to go into the atmosphere anyway (through decomposition processes). Not to mention, we could cut a lot of methane release.

    Wait for it – new and better things will come.

    1. Yes, nice idea… You can burn your garbage, reduce your landfills and get energy out of the deal. Right?

      Well, except…

      Most garbage is of really low calorific value, and burning it doesn’t really give you much in terms of energy, unless you process it in various ways. And when you process it, you’re actually _adding_ energy, which further reduces its return on invested energy. I’ve seen plans for pyrolysis plants that actually required _pouring fuel_ on the garbage to make it burn!

      And, in most of the world, there’s no source-segregation; plastic is mixed in with biomass, metal and glass. Burning that concoction will not only give you energy, but also a free, life-time unrefusable offer of dioxin and furan production. Not a good idea burning it at all!

      Besides, after composting (essentially zero-energy spent), the bio-fertilizer left over can be used to grow bio-fuel plants (say the prairie plant mixture that David Tillman came up with), or for growing food. And the by-product of that composting is probably going to be methane – aka, natural gas. Why waste a resource by burning it?


  7. whats that adage, we’ve learned to burn our food but unfortunately we still can’t eat our fuel.

    i’d love to be able to use the E85 in my car, its much cheaper here in Indianapolis, IN USA and more stations are picking it up.

    I wonder what kind of conversion kit I can get for my 01 ford focus… it looks like you just need to dump a little more into the engine. Hell, maybe a custom flashed ECU could handle that!

    too bad kerosene is always MORE than regular petrol, but gone are the days where one could simply add an additional head gasket to lower compression to use it.

  8. It’s not just fertilizers, but also the poison Roundup that is sprayed on all corn fields these days. Don’t forget that the agri-business corporations are making billions on the system where they sell all the inputs: roundup-ready seeds, fertilizer, roundup itself, fuel, and equipment, then they collect and distribute the corn while the farmers are at the mercy of the markets. It can be good for the farmers but only if the agribusiness polluters get their cut first.

  9. To get a sense of Maggie’s point that liquid fuels “allows you to stuff a lot of energy into relatively small amount of storage space”, compare the energy density of batteries and gasses with liquid fuels:

    Battery technology does follow a kind of Moore’s law, but unfortunately it’s doubling period is more like a decade, compared to the 18 months(ish) of the real Moore’s law:

    Electric cars are just about becoming viable now, but liquid fuels will be much more convenient for many years to come. If only they didn’t come with so much environmental baggage…

  10. Why is there such a push to create another explosive volatile, hard to store, hard to transport gasoline facsimile product from FOOD crops no less? We have BIO-Diesel which still has some the same challenges as mentioned here but is all but unprocessed oil that won’t explode, burn easily, is bio degradable safe to transport and can be produced from lots of diverse non food sources. I think its a fear of losing the distribution channels, thus control of the market, that is driving the trend to highly processed products that use existing infrastructure and markets.

  11. There’s one thing that the media never mentions about corn ethanol:

    Producing corn ethanol also makes distillers grains, a high-protein animal feed.

    This is mixed with the remaining water from the distillation process and can be sold wet, or dried out to make DDGS, dried distillers grains with solubles. Although it accounts for about 1/3 of total production, it currently represents about half of an ethanol plant’s income. Somehow this is never mentioned in stories about ethanol, even though it’s a major factor for plant profitability, and has lessened the resistance to ethanol by meat producers because DDGS is much cheaper than other high-protein fees like fish meal.

    1. This is hardly some sort of secret. Those products are vital parts of the energy computation for corn ethanol and are in every study. The only way corn ethanol can even be considered a net energy gain is to take those into account – if you grow corn _only_ for fuel, it is a horrible energy sink. What do you think will happen to the marginal value of these products when corn production increases? And will cattle feed be a big requirement in a lower energy world that presumably will be eating less meat?

  12. I read Tillman’s original paper and there is a bit of smoke and mirrors going on. Yes, his mixed prairie did produce more than unfertilized switchgrass, but it produced just a fraction of the biomass from fertilized switchgrass fields. It’s like discovering you can get more meat from a chicken than a cow if you only feed them one cup of corn a day.

    1. One of the important findings is that we can produce a reasonable amount of biomass =without= the use of fertilizer. Please see the numerous articles available online regarding the impact of nitrogen fertilizer runoff, and why we need to find ways to produce biofuels without the use of fertilizer.

  13. Good piece on a very important energy topic that seldom floats anywhere near the top. Land-use in particular is very concerning, since we’re facing increasing populations and less and less arable land in this century.

    How much land can we devote to liquid fuels when people are going hungry? That suggests to me that such fuels will become too valuable (like He3) to throw away on mere travel. If so, then progress on the storage front is critical.

  14. Thank you, Maggie! If you spend a day poking around USDA’s landuse statistics, the claims that biofuels are pushing out food look really ridiculous. About 38 million acres are used for the corn that goes into our ethanol. There are 30 million acres of cropland (farmed at one time) that have been taken out of production because of low commodity prices. Hell, there’s 20 million acres in lawns; 90 million acres of exurbs; well more than 100 million acres of land devastated by coal mining.

    BTW, replacing corn with fodder beets (or similar high starch root crops) would double yield and use the same tech as corn (unlike cellulosic, no new enzymes required).

    1. see my comment about Joel Salutin and Polyface farms. Grasses are the best solution for raising beef and improving the soil.  I think 50-60% of corn is for animal feed, 17% for food products and High Fructose corn syrup in products, chips, pop etc. and 25% for export (2005)
      It doesn’t make much difference in raising the cost of food for Americans and Canadians – we only spend something like 9% of our budget on food but the amount that is exported and rise in price of corn on the world market does make a difference in countries like mexico where it is much more of a staple and food makes up a bigger part of the budget.  Look at the connection in the rise of food prices in north africa and the Arab spring.

  15. “If all fossil fuels and their derivatives, as well as trees for paper
    and construction were banned in order to save the planet, reverse the
    Greenhouse Effect and stop deforestation…

    Then there is only one known annually renewable natural resource that
    is capable of providing the overall majority of the world’s paper and
    textiles; meeting all of the world’s transportation, industrial and home
    energy needs; simultaneously reducing pollution, rebuilding the soil,
    and cleaning the atmosphere all at the same time…

    And that substance is—the same one that did it all before—

    Cannabis Hemp…Marijuana!”

  16. In the natural gas arena, the NatGas peeps ask you to overlook a Big Thing: Emissions are not restricted to the tailpipe, as they largely are in traditional petroleum usage.  In NatGas production, large amounts of N2O are burned, one way or another, at the well or compressor head, along with SO2. Huge volumes of CO2 and a fair amount of O3 are simply vented. Although many operators are capturing and compressing CO2 for use in pressurizing old oil fields, the CO2 inevitably is vented at some point.

    In addition, the ‘amounts of natural gas larger than all the oil in Arabia’ you may have heard about, are dependent on ‘frakking,’ a technology that will quickly contaminate our water into unusability, for centuries. I don’t say ‘may’ or any other hedge word. The techniques and materials in use today have contaminated and will continue to do so. NatGas is NOT a clean fuel. Once, when NatGas was a by-product of conventional petroleum, it was very clean in comparison, but it is no longer even remotely so.

  17. I think it won’t be a tragedy if the US no longer overproduces its corn.
    It will give other countries like Mexico a chance to sell their corn in
    other markets. Currently we import it because US corn is cheaper! But
    that’s only because it’s subsidized! It’s fake! Foreign markets would
    benefit ultimately from the US actually using up its corn product.

    The history of corn subsidies in the U.S. is interesting.  Link

    So why did Earl Butz implement a policy that guarantees overproduction of corn and declining yearly revenues for farmers?  At the link, Michael Pollan is quoted talking about the impact of food prices on politics — which is an important factor.  But taking a slightly longer look, consider how much less likely an overthrow of the government is when nobody’s hungry.  Even if everything else goes to pot people will probably be relatively content if their kids are fed. 

    My guess is that the corn subsidies are basically a move to create a strategic carbohydrate reserve to go with the strategic petroleum reserve.  The government controlling a huge pile of corn pretty much guarantees they can exert some degree of control over Americans regardless of whatever disasters befall the country by extorting them with high calorie food.  This might not even be a bad thing, Big Bother (not a typo) might very well be better than millions of people starving to death.

    1. A strategic carbohydrate reserve — that’s pretty insightful. We also have an interest in helping feed other countries, for the same reason: hungry people are crabby, restless people.

  18. Just because large-scale biofuels might have flaws doesn’t mean there aren’t small-scale biofuel solutions available now that are quite sustainable.

    For the last two or three years I’ve been running on 100% post-consumer waste recycled biodiesel. It is available at the pump in many California cities. All you need to run this fuel is a diesel-powered vehicle from the 1980s or later. No conversion is needed. 

    Fuel prices are higher than conventional diesel, but with the large MPG boost of switching from a gas car to a diesel car, I end up with about the same overall fuel costs as running a gas car.

    True, the sources for recycled fuel are limited. There’s only so many french fry vats in America. As more people get into recycled diesel the prices will rise. Yet there’s still room for more recycled diesel consumers. 

    1. You’re not restricted to recycled waste veg oil, though.  You can run on mineral diesel or even just plain cooking oil if you have to.

    2. Emergent phenomena apply here. As more people switch to recycled biodiesel, the overall impact of running personal vehicles declines as a result of the aggregate. We don’t necessarily need a national policy or new legislation. We just need enough people to make the changes on their own, and the savings in terms of money, environmental impact, and so on, will emerge from the collective actions.

  19. You know, I once had the brainstorm of going thru the South, hiring crews to dig up kudzu roots (which can grow as big as humans) & using ex-moonshiners to make alcohol out of these starchy roots.  We would sell the alcohol as ethanol & as booze.
    Then I popped open another beer . . .

  20. My biggest issue with corn isn’t that it’s bad.  It’s that other things are better yet the US government throws billions upon billions at corn as if it was the only solution.

  21. yesbut… I respect that technology is always part of the solution, and not to get toooo far off topic, here…

    I know that some of you love your cars and the freedom they bring, but it would be nice to start exhibiting some market pressures towards smaller, higher density housing, livable cities, reasonable sized food portions, etc… before the markets put the pressure on us.  Save the fuel for longer distance travel and shipping.

    My girlfriend was in a city planning studio at a certain college.  They did a project that re-envisioned a certain city.  The major critique from one of they professors was: how was he supposed to get to Tahoe on the weekend without his car, which didn’t figure into their plan of the future.  Lord knows that alternative transportation to the slopes exists, and certainly could be improved upon.

    Biofuels and other alternative fuel sources don’t really address the problem at the root, which causes a lot more problems, such as noise, congestion, huge neighborhood dividing streets, etc.

    I only mention this here, because in my opinion, despite all  the realities of the world, a carless future is a future worth fighting for, and which technologies such as biofuels only prolong.

  22. Mmmm, Biofuels discussion!

    I’ve been running nearly 100% Biodiesel since June of 2003 (Dodge Ram 2500 Diesel) and 76k miles later am a huge advocate of biofuels (though I’m still not on board with corn based ethanol).  A couple of points I’d like to make.  rom the start, biodiesel was really empowering to me: I belonged to a coop and we made our own fuel.  It was easy.  Now commercial BioD is readily available and I like to support the industry.  I chose specifically to go with biodiesel instead of SVO (straight vegetable oil) as I wanted to promote that you don’t need to make ANY modifications to a diesel engine to run 100% BioD (As i understand it, there are issues with injector scoring and piston head deposits with SVO, though admittedly I haven’t done complete research into it).

    1. Most virgin biodiesel is coming from soy, which is unfortunate.  Soy is certainly not the most efficient crop to get raw oil from (rapeseed has a much better yield per acre). But it is BigAg (Monsanto/ADM) that is the driver of soy (as well as the government subsidies). Now that it is established as a viable fuel we need to move away from soy (and as mush as I like Hemp as a crop its not optimal as an oil source (low yield and energy intensive extraction)

    2. The most promising source I’ve seen as a source vegetable oil is sea algae: Huge yield, low energy oil extraction, can be done on land mass without affecting food crops. I’ve known about this for more than 5 years and large scale production should be trivial and while some progress can be seen is being made I am frustrated at the current state.
     See video here:

    3. The biggest problem with BioD is the NOx emissions. Though this can be dealt with as market demand increases.

    I do agree that Biofuels are not an “end-game” solution. You end up battling the same issues if you don’t address urban design and transportation issues.  However, biofuels should be a large part of transitional energy design.

  23. i apologize to the Moderator, however feel there is no need to even discuss corn as a viable source of ethanol and will continue to advise people to do even the slightest research on hemp based fuel. it is rather unfortunate such an informative article on bio fuels fails to mention the most reasonable source.

  24. As MKB points out, biofuels have the advantage of energy density and compatibility w/ existing vehicle fleets and infrastructure.  As such, they have a role to play in the transition to an environmentally-sustainable energy economy.

    Otoh, the theoretical upper limit of conversion efficiency (solar power to energy) of photosynthesis is less than 10%, with actual results with real plants in mass cultivation much lower even before you factor in energy costs of cultivation and processing.   Theoretical – and practical – efficiencies  for both photovoltaic sells and solar thermal electric (CSP) are many times higher. For example, today’s commercial solar PV cells operate in the mid-20s and cells in labs are exhibiting close to 40% efficiency. (working from memory here, so my figures may not be exact).    The obvious conclusion is that, even ignoring water consumption, food impacts, etc.,  satisfying civilization’s energy demands using solar power will require 100s of times less land area if we use machines and not a biological process (photosynthesis) as the primary conversion.

  25. There are 2 points in these sorts of discussions that I never see mentioned:

    1.The main benefit to bio-fuels is that they are renewable. This is because they rely on processing readily available materials in a relatively short amount of time, instead of needing to be buried for millions of years. Doesn’t this mean that most of the carbon contained in the plants used to make bio-fuels actually comes out of the air in the first place while the plant is growing? Doesn’t this mean that the CO2 contribution to the atmosphere is almost completely cancelled out, since the carbon cannot be released more quickly than it was absorbed? Fossil fuels create a carbon problem because they re-release carbon into the atmosphere at a much quicker rate than the millions of years it took to store it in the first place. Do the greenhouse contribution statistics mentioned in the article above take this into account?

    2. The article mentions that the creation of bio-fuels being better for the environment is currently dependent on natural gas being used as the primary fuel source for it’s production, instead of gasoline. Why can’t they use the bio-fuel they are creating as the fuel source, and remove the fossil fuels from the production entirely?

    1. Hi bkofford,

      you ask the right questions, and the sad answer is:
      To produce on gallon of biofuels you need energy roughly in the order of one gallon as well.

      So in terms of energy content you need a second energy source (for example natural gas).
      May be we should use solar energy or wind for that.

  26. “But here comes our friend, the yesbut. Yes, you can get an emissions benefit from corn ethanol. But, this only works if the ethanol plant is powered by natural gas. If it runs on coal, you’re not reducing emissions at all.”

    If ethanol is net positive in terms of energy, why doesn’t the ethanol plant run on ethanol? I might believe in it then.

  27. “a gallon of corn ethanol can reduce greenhouse gas emissions by somewhere between 18% and 28%, compared to a gallon of gasoline”

    I think the word “reduce” here is inappropriate and facilitates greenwashing. Producing fewer greenhouse emissions does not equal reducing greenhouse emissions.

    1. That’s not even the real problem with that sentence. Any time you’re comparing ethanol to gasoline by the gallon, you’re already greenwashing. Ethanol has about 70% of the energy density of gasoline. (24 vs. 34 MJ/L)

  28. This does nothing to dispell the basic shortcoming of so called bio-fuels.  It’s totally a waste.  It might be profitable for someone in the chain, but the bottom line is it takes more energy to create than it produces, plus it just makes food that much more expensive for the worlds starving people.

  29. I’m always miffed by a discussion of bio-fuels that leaves out biodiesel.  Biodiesel *IS* produced at scale unlike cellulosic ethanol, and does reduce GHG emissions by 80%.  And that’s when using virgin soy-based biodiesel.  With recycled fryer oil, the reductions in GHG emissions is even higher.  I guess people don’t talk about biodiesel in the US because diesel engines in passenger cars are still a novelty here.  In Europe, more than half of new passenger cars are diesel powered.  Modern diesel engines are so vastly superior in every measurable way to their gasoline counterparts, that their rarity in passenger cars in the US is a complete mystery.

  30. I live in New York City and ride my bike mostly- but I do have a diesel-engined VW Golf for when I need to drive. I got it specifically to run on biodiesel, but the problem here is that there is only ONE source of biodiesel I can find, and it’s far up in the Bronx, not open on weekends, and only open for short periods of time on weekdays. I don’t have the space to set up a filter kit and do the SVO thing, so the question is- for those of us who WANT to switch, what options do we have? I would support any of the suggestions made in this discussion if they existed… but they don’t, not in freaking NEW YORK CITY! So what chance do any of them have of taking hold if the few people that want change to occur can’t even participate…?

    Anyone know where I can get biodiesel?

    1. I just did a Google Maps search on NY NY and found something like a hundred hits mentioning biodiesel. I’d go through that list and call those companies to see if they offer it to the public via a pump. Some companies only deliver in quantity to fleets. 

      1. In fact, all of those companies do except for the one mentioned. I probably haven’t called every hit you found on google, but I’ve done a lot of calling (6 months ago, anyway) and Tri-State Diesel in the Bronx is IT. Sad, but true, unless someone knows of a specific place they can recommend. It’s crazy to ponder!

  31. I haven’t gone through the comment list to see whether the following point has already been noted, but it bears repeating anyway, the GREET info cited is false.  Here’s the quote:
      “But here comes our friend, the yesbut. Yes, you can get an emissions benefit from corn ethanol. But, this only works if the ethanol plant is powered by natural gas. If it runs on coal, you’re not reducing emissions at all.”

    In their study of fracking from late 2010, Profs. Ingraffea and Howarth of Cornell, using conservative figures from the methane gas industry, concluded that greenhouse gas emissions from drilling for methane gas using fracking (fracking accounts for 90% of U.S. gas production today) are actually WORSE THAN COAL. You have to take into account the emissions from start to finish, drilling to burning to get the real picture. This, by the way, is in no way a defense of coal mining.  Switching to true renewables should be the primary agenda of Obama’s administration. Instead, he’s fostering fracking around the country and abroad, poisoning our air, water, and food supply.

  32. good point tacoblaster,
    see (NASA/TM—2008-214833, Fig. 6) for exactly this life-cycle analysis. 
    If we do not find a way to produce BF the green house gas emissions will only drop by 50%.

  33. What about another high sugar crop grown in a 3rd world country like say sugarcane? If this crop produces more sugar per input of fertilizer/pesticides then it make the carbon equation better. As a bonus what if you decrease the fossil fuels needed to plant, harvest and process it by using animal or human labor? That makes the carbon equation even better.

    Forget the lost american jobs, its a sacrifice for the environment

  34. The discussion should also open up to alternatives like methanol, which can be generated directly from any cellulose matter (including food waste) in plentiful enough quantity that it would be ridiculously easy to 100% replace existing liquid fuels.

    Methanol is more toxic than ethanol, but only to the degree that gasoline is now.  It’s used widely in consumer and industrial usage, without special precaution.Perhaps a gradiated system, with personal transportation running on ethanol or biodiesel, trucks and trains and jets running on methanol, so that the fuels closest to the most people are the safest for those people.

  35. What’s weird to me about the use of corn as biofuel is that a corn plant itself is mostly cellulose, the stalk, the leaves,  the corn cob, etc.  all seem like they would yield far more energy than the seed itself.

  36. They aren’t looking at the unintended consequences of burning one of the US’ main food cereal crops: FOOD prices go up.   Livestock feeds also go up, pushing up the price of meats.   Cost of pet & horse ownership goes up.      I own horses. People call me desperate to give away their horses.    Since 2006 hay has at least doubled in cost and horse feeds have gone up 50-80%.    Dairy farmers are getting out of the dairy business, so if you like cow milk, it’s going up, too.

    And when price per bushel of corn goes up, farmers race to plant more corn.  So now they’re plowing under other cereal grains, hay fields, and vegetable plots.   Supply and demand means now the price we pay for these other sources of food goes up.   

    Instead of destroying a food source, why don’t we stick to biofuels from things humans don’t already need?    

    Or an even crazier idea for America:  energy conservation.    Higher mpg standards in place now, not 20 yrs from now.   Incentive for electrical and heating conservation use.    Some way to penalize the people who build 10,000 square foot McMansions because they’re burning up to 10x as much energy heating and cooling the monstrosity as a basic townhome.  

    And whatever happened to all the green jobs & industry we were promised at the last election?:   I’d happily put solar on my own home if I could find an installer in my county.   

  37. Bio Fuel is just repeating the same problems of fossil fuels.

    Hydrogen is the only thing with a future.

  38. Corn is not the only thing that we can make ethanol out of. Some of the things we can make ethanol out of are far less resource intensive. How’s this for a wacky idea: grape-based ethanol fuels. There are places where grapes grow, but may not be great for wine because of various issues. There are also places where the grapes grown for wine can be terrible in one year because of the weather. 

    I’m thinking specifically of the problem in Walla Walla, WA right now where the grapes have been hit hard by mold *and* frost two years in a row. There are grapes out there, but a lot of them are just not going to be turned into wine this year. If we took this year’s grape harvest and turned it into fuel instead of just throwing it out, that would be of great financial and ecological benefit to the region.

    We could be turning the enology students from Walla Walla CC and the brewing science students from Oregon State into Northwest fuel specialists.

  39. Here is the misconception.  Regardless of the fuel source you can only get as much energy out of it as was used to produce it.  All this talk about producing bio-fuels which use less energy to produce than they store is silly.  The simple fact is that all bio-fuels get some of their energy from the sun and when you figure that into the equation, you discover that ALL fuels only give back a portion of the energy that was stored in them.

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