It seems Tim Searchinger has a real problem with biofuels, particularly corn-based ethanol. Judging from his most recent attack on biofuels, which was disguised as an article in Science Magazine, Searchinger is still not convinced that biofuels are better for the environment than petroleum. This is ludicrous, of course, but the ethanol industry's representative groups must once again retaliate with truths about the environmental impact of ethanol production. Following are excerpts from some of the responses.

Renewable Fuels Association: "There is undeniable evidence that the climate concerns we face have been caused in large measure by the reckless use of finite fossil fuel resources. Developing a host of renewable alternatives, including from biomass feedstocks, should be a central goal. While recognizing that all carbon-based energy has associated carbon emissions, we must look for the least carbon-intensive alternatives and favor approaches that ‘recycle' above-ground carbon. Based on a fair apples-to-apples comparison with petroleum, biofuels clearly offer society a lower-carbon path forward.

"The real issue is not accounting tactics, but whether biofuels reduce GHG emissions compared to continued petroleum use. There is clear and substantial evidence that they do."

Growth Energy: "Ethanol is part of the natural carbon cycle. It has taken the lifetime of our planet to produce the oil that is in the ground. Biofuels come from the top of the earth, with emissions that are used by the next year's crop in a recycling of carbon. What this study suggests would give an indirect benefit to oil – they're saying it's OK to pump oil out of the ground and use trees to absorb the carbon. But that does nothing to address our country's dependence on expensive and carbon-intensive fossil fuels like oil, extracted from overseas oil fields or tar sands, where emissions are three to five times the rate of normal crude oil production.

"In truth, there's no new science in this report. It's a policy proposal, trying to get a new standard that would limit the ability of developing countries to provide food and fuel – and would keep our own nation addicted to imported oil. It would penalize U.S. farmers for the decisions of foreign competitors, over which we have no control, and threatens the sovereignty of American agriculture."

Advanced Biofuels USA: "Emissions from all sources of energy should be accounted for using scientifically respected and tested methods; energy policies should reflect those findings; and pressure should be placed on those who directly make policy and who can implement improved ecological practices where ever they are in the world.

"The farmer in North Dakota is going to sell corn at the best price the market will bear, not asking if it is going to be used to feed hogs, contribute to obesity via soft drinks, make compostable cutlery and carry-out containers, or to be turned into ethanol to enhance the octane of gasoline or decrease our dependence on foreign oil. That grower will feed the market to the best of his or her ability to make the best profit possible. That takes plenty of skill, knowledge and work. Don't also burden that farmer with responsibility for ecologically destructive land use policies and practices in a country half way around the world."