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US scientists puncture the ethanol biofuel bubble

Crop switch likely to increase emissions

Good science news (or bad, depending on your point of view) has arrived with two reports on the carbon footprint of biofuels, in the paper edition of Science magazine. They deal serious damage to the belief - which up to now has been driving the biofuel bubble - that stepped-up ethanol production in the US is an answer to global warming.

Writing in "Use of US croplands for Biofuels Increases Greenhouse Gases Through Emissions for Land Use or Change," Timothy Searchinger and many others state: "To produce more biofuels, farmers can directly plow up more forest or grassland, which releases to the atmosphere much of the carbon previously stored in plants and soils through decomposition or fire. The loss of maturing forests and grasslands also forgoes ongoing carbon sequestration as plants grow each year ..." (A companion piece, "Land Clearing and the Biofuel Carbon Debt" by scientists at the University of Minnesota, covers similar territory.)

The scientists step on switch grass, too, a weed peddled by those promoting the still largely theoretical panacea of ethanol production direct from cellulose. "Biofuels from switchgrass, if grown on US corn lands increase emissions by 50 per cent," write the authors in the lead paragraph.

The news tosses a good deal of water on the biofuel fire. Unfortunately, the reports are subscription only and while there were a number of pirated copies flowing in email due to the electronic publication of the news last week, the perfectly awful figures still deserve some reporting. For example, the New York Times story on the reports ignored ugly figures like the percentage losses in feed crops contrasted with increases in emission, perhaps figuring correctly that the average reader is too stupid and easily bored to tolerate them. Since the Times has been a cheerleader for miracle alternative energy solutions, the reports were surely hard for it to swallow. One could imagine the nervous gulping in the paper's second sentence. It noted that ethanol mania, therein called the "benefits of biofuels," had come under attack and that the articles in the magazine would "add to the controversy."

This is what happens now in the US when fairly clear cut, inconvenient and unpopular peer-reviewed science shows up in the public arena. As far as mainstream journalism is concerned, it generates a "controversy." In the current political context, controversy is good because it can be used as cover, deployed by the various interests who stand to make a fortune from a boom predicated on previous received wisdoms now contradicted by more rigorous thought.

The authors conclude in Science that as the US ramps up biofuel production, other crops will decline - "corn by 62 per cent, wheat by 31 per cent, soybeans by 28 per cent, pork by 18 per cent and chicken by 12 per cent." The general reply to this is to claim that boosted crop yields on remaining land and greater efficiencies will make this up. Not so fast, reply the authors, stating their figures are already based on the assumption of growth in yields but that "positive and negative effects, "the latter from factors like "reduced crop rotations and greater reliance on marginal land," cause a canceling out.

Declines in production of feed grains due to biofuel diversion cause significant cuts in food exports. Brazil, China and India then cultivate more arable land for food crops. This is a double whammy, not only releasing carbon dioxide locked up in plants and soil in the US but also around the world. It's a strong and compelling analysis of the current US rush to ethanol. Indirectly, it's quite an indictment of it, too.

The choices presented by the study are harsh ones. The pooch is so screwed by current greenhouse gas figures that even with the reining in of biofuel production so that only a much smaller slice of feed grain - 10 per cent - is diverted, cuts in emission then come through with human cost. They adding a little starvation to the balance sheet.

"Counteracting increases in biofuels with controls or disincentives against land conversion would face not only great practical challenges, but also have harsh social consequences," the authors write. The smaller reduction in land use for ethanol as opposed to feed crops would still result in a diminution of production of world milk and meat, the effect of which would reduce carbon dioxide release but at the same time depress poorer diets in developing nations. "In that event, more greenhouse benefits would stem in reality from reduced food consumption," it states. The authors write with a bit of delicacy that this effect is "probably not a desirable one."

The report puts those pushing the fad of biofuel into a real corner. There are no miracles forthcoming and all of the talk about transformative technology seems to be just that. The authors stress that their results mean that only ethanol production from waste material stands not to add to greenhouse gas production and then only if it is conducted under a strict regimen. This means the possible use of cellulose, but only in a system in which good cropland isn't turned over to cultivate the biofuel weed, switch grass.

None of this can be good news to biofuel producers although in the short term it would seem unlikely to seriously impede their current plans. There is too much greed and politicized government subsidy plowed into US biofuels to expect rationality to prevail and brakes to be applied, even gently, immediately.

The final conclusion in Science has the ring of common sense: "[When] farmers use today's good cropland to produce food, they help to avert greenhouse gases from land use change."

Additional note: In January, just one day after George W. Bush's state-of-the-union address, the Department of Energy cancelled its support for a "clean coal" electricity generating facility in Mattoon, Illinois. It effectively killed the project. Called FutureGen and employing Fischer-Tropsch processing, the plant was viewed as a key prototype in the country's energy security future. However, the sticking point on it was its production of carbon dioxide. No one has been able to practically address what to do with it other than offer up the airy fancy that the greenhouse gas be stuffed into the ground, the functional equivalent of an instantaneous miraculous solution.

Taken together with Science's dual reports on biofuel land use causing increase in global carbon dioxide emission, the beginning of 2008 has been a shock to the American belief that silver bullets for energy independence and curbing climate change are nigh. ®

George Smith is a senior fellow at, a defense affairs think tank and public information group. At Dick Destiny, he blogs his way through chemical, biological, and nuclear terror hysteria, often by way of the contents of neighbourhood hardware stores.

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