Carbon trading for ethanol

Corn at pumpThe letters section in last week’s Science Magazine (pdf) got us scratching our heads once again about the ethanol path we are headed on, with 39 new plants currently scheduled for opening.

The letters reveal a lot of disagreement about the impact of the processes that underlie corn-based ethanol production. And since the study, many bloggers have pointed out that the use of coal in new plants like Heron Lake Bio Energy largely wipes out any greenhouse gas reductions from ethanol.

Much of the problem is obtuse legislation that neglects the ostensible goals of a switch to ethanol-based fuels. For example, ethanol, however it is produced, gets a $0.51 per gallon tax credit. Ethanol, however it is produced, meets renewable fuel standards in the Energy Policy Act. That’s good news if the aim of the legislation is to promote production of ethanol, but not necessarily good news for the environment.

These laws are blunt policy instruments. We like sharp ones, such as carbon trading. Under the proper protocols, each ethanol plant could create carbon credits according to the specifics of their production process. Gas-fired plants create more credits, coal-fired plants create little to none. Trade in these carbon instruments could be used to encourage lower full-cycle emissions, as well as provide a carbon bonanza for the first to commercialize cellulosic technologies.

We’re a long way off from an economy-wide trading regime, but perhaps biofuels are the right place to start incentivizing the behaviors we want.

Footnote: One zinger in the letters section that shocked us: using current processes that yield about 60 gallons of ethanol per acre, planting the entire state of Iowa with corn would provide only enough fuel to satisfy consumption in the U.S. for about five days. In other words, we’ve got a ways to go before biofuels are scalable enough to support our energy needs.

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  1. Anonymous - July 5, 2006

    Yes many things cause scratching of the head—There is a doc out called, “Who Killed the Electric Car.” All electric cars require no new tech to produce and use, Charging with fast chargers, better battery’s, hybrid tech to help recharge, solar on car roofs to help charge, and malls could install charging stations an charge a nickle an hour to charge your car while you shop—and of course all malls should have solar cells on their roofs. Seems GM needs to layoff 25,000 people, yet tired old manegement once again blames the workers–was it not their choice to pull off the road/market the electric cars they produced for Califorina—how come Honda sold 60,000 hybrids already—GM?

  2. William Tokash - July 5, 2006

    Tom, I am curious, I could not track your reference on the “60-gallons per acre” item above. The number I’ve seen used from a “fenceline yeild” standpoint is 150 bushels of corn per acre and 2.7 gallons of ethanol per bushel. What were the assumptions on your reference?

  3. Tom - July 5, 2006

    Reference is from letter itself (see link above). Their logic is that if energy balance is 1.2:1 then 60 gallons is the right number, not ~400 gallons.

  4. Mike - July 10, 2006

    Do you have any information about the petrol used to make the fertilizer required to get the corn production we currently have? Specifically, does the method for synthesizing fertilizer from oil release carbon? If so, how much?

  5. Adam Stein - July 10, 2006

    Hey Mike,
    I just finished plowing through the book The Omnivore’s Dilemma, which I plan to blog on soon. The book dwells quite a bit on your question. The answer to your question is an emphatic yes. Here’s the relevant quote:
    “Every bushel of corn requires the equivalent of a between a quarter and a third of a gallon of oil to grow it…Put another way, it takes more than a calorie of fossil fuel to produce a calorie of food.”

  6. Noah - July 12, 2006

    Let’s not write off ethanol altogether, lest we forget that the ethanol comes from fermentation & fossile-fuel-powered distillation. Where corn acreage is limited, we should consider the other sources of biomass to ferment (animal/human/plant waste, etc). Where fossile fuel distillation tips the scale one way, solar/wind/etc based distillation will tip it back the other. I’m glad humanity is getting this concept going, we just need to refine the process.

  7. Joe - July 12, 2006

    I’d just like to add one simple thing that so many people either forget about or just think is crazy talk but here goes… There is no valid reason, other than brainwashing by companies like Monsanto and their GMO corn, that the corn used for ethanol production cannot be grown using organic methods. There is absolutely no reason to use petroleum based fertilizers and weed killers and insecticides! Studies even show that in properly managed fields, organic outproduces most fields grown with the poisons so commonly used today. Just something to think about…

  8. Adam Stein - July 14, 2006

    Joe –
    I wish this were true, but my understanding is that there is no way that the yields currently achieved by corn farmers could be sustained without nitrogen-rich fertilizers derived from fossil fuels. The soil simply can’t support that level of production. And even if it were true that nasty chemicals could be avoided, the corn would still have an extremely high carbon content — 4/5 of the energy used to produce our food goes into processing and transportation, and these steps are the same for both organic and “conventional” foods.
    This is in no way a knock at organic foods. It’s just that organic production methods won’t fundamentally alter the carbon balance for corn-based ethanol.

  9. Anonymous - August 16, 2006

    The 60-gallons-per-acre figure calculated by Constanza et al was based on adding up the energy value of all the energy going into corn and ethanol production (mostly natural gas and coal) and then deducting that value from the energy in the ~400 gallons of ethanol actually produced per acre.
    But that coal and NG energy isn’t a liquid transportation fuel. We could turn it into a liquid to put in your car – through coal-to-liquid or gas-to-liquid technologies. But these technologies would yield a lot less than 340 gallons. The whole idea of “energy aggregation” (adding up different types of energy as if they were the same) in this context is disingenuous.
    The EBAMM model showed that the actual petroleum energy (a liquid transportation fuel and legitemate comparison to ethanol) going into corn and ethanol production is 0.05 units for every 1 unit of ethanol.

  10. Tina - September 2, 2006

    In Brazil they use sugar cane to make their ethanol, which apparently yields about 8 times the energy as corn? Corn is NOT the ideal thing to make ethanol from, but we have these “interested parties” like Cargill, Monsanto, etc. who have powerful lobbies and so, heavily subsidized corn becomes the plant of choice. Sickening. It seems to me that should be a big part of the discussion, the best crop to grow to make ethanol, and corn ain’t it. Can’t we grow sugar cane, sugar beets, whatever? That being said, whatever gets us off oil is a step in the right direction, I suppose, at least geopolitically.
    And when the cellulosic ethanol becomes reality, and the stalks and all can be used as well as the ears, then I guess it might all balance out.
    Although growing FOOD to burn as fuel seems somewhat distasteful with so many starving people in the world. I suppose that’s a different can of worms, but still…

  11. Samuel Howe - September 6, 2006

    I hope you enjoy this E-mail —DAD—

  12. Anonymous - September 6, 2006

    Ethanol isn’t the best choice. however , butanol is better, cost more to produce and yields are low. more research needs to be done to improve the yield plus alternate energy sources to heat to extraction temp. ecomonically.

  13. Anonymous - September 6, 2006

    Tina, you got the facts. It is true farming has been taken control by agribusiness interest like Monsanto and Cargill. They feed the U.S. untested GMO’s. In some ways maybe they should burn all the plasticised grain in mechanical engines instead of human engines.
    SEEDS of DECEPTION – Jeffery M Smith, AGAINST THE GRAIN – Richard Manning, and DIET FOR A DEAD PLANET – Christopher D Cook all have info on the modern agribusiness structure.

  14. Anonymus - February 25, 2007

    Could anybody help me in providing a information how can be molasses basis Ethanol plant can bnefited using carbon credit scheme !.