WASHINGTON – At a hearing hosted by the U.S. Environmental Protection Agency (EPA), Dr. Mark Stowers testified that the EPA’s proposed rule to determine the greenhouse gas emission performance of biofuels is “flawed and has no basis in law or science.” Dr. Stowers represented Growth Energy at the hearing and serves as Vice President of Science and Technology for POET, one of Growth Energy’s founding members and the world’s largest ethanol producer. The hearing centered on a controversial theory called indirect land use change, which would penalize American ethanol for greenhouse gas emissions that result from land use changes around the world.

Indirect land use change theory uses speculative models and incorrect assumptions in an attempt to blame American farmers for deforestation in Brazil. According to the theory, corn used for ethanol displaces other crops, like soybeans. As the theory goes, this causes farmers in other countries, such as Brazil, to cut down rainforests to grow soybeans and fill the demand.

Yet, the science behind this theory is far from settled. In fact, in Dr. Stowers’ testimony, he noted that even the EPA has strong reservations about using such indirect land use change models. “EPA’s proposal also is arbitrary – particularly when considering EPA’s own findings in its 2009 proposed Greenhouse Gas reporting rule that measurement of greenhouse gas emissions from agricultural sources and land uses are ‘prohibitively expensive,’ ‘complex and costly,’ ‘technically difficult,’ ‘impractical,’ and ‘have a high degree of uncertainty.’

Dr. Stowers also noted that the models have severe problems and limitations that have not been validated through appropriate sensitivity analysis. Some of these problems include comparisons that hold emissions constant from all fuels, limited actual land use data, failure to make apples-to-apples comparisons with gasoline by not including indirect emission effects for that fuel, failure to consider the impact of political drivers on land use, underestimation of offsets from ethanol co-products, and underestimation of corn and ethanol yields.

Dr. Stowers ended his testimony by inviting officials from the EPA to visit a modern ethanol plant, “and obtain real data about the industry rather than relying on unproven models, hypotheses, and assumptions, and encourage the agency to solicit meaningful input from industry experts and revise the proposed rule based on the best available data and validated science.”

Please find Dr. Stowers’ prepared hearing testimony here.

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