Cellulosic Ethanol Finds A Friend In Hot Water

The U.S. Environmental Protection Agency (EPA) was originally counting on U.S. ethanol producers to mix 500 million gallons of cellulosic ethanol into the country’s gasoline supply in 2012. Ain’t happening—by a long shot. After ethanol producers indicated that they would fail to meet the 2011 renewable fuel standard, the EPA reduced its 2012 mandate to a mere 8.65 million gallons.

Alas, even this modest target will be difficult for producers to meet without significant cost reductions. (The Obama administration has tried to prop up the fledgling industry with loan guarantees for cellulosic ethanol plants in  projects in KansasIowa and Oregon.)

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image via Oak Ridge National Laboratory

Criticisms aside, part of the problem is that the current method of producing ethanol from cellulosic feedstocks like switchgrass is expensive. The two-phase process requires the use of expensive enzymes that break down plant materials to yield sugars. The sugars are then fermented into ethanol in a separate process.

However, a recent study by scientists at the U.S. Department of Energy’s BioEnergy Science Center at Oak Ridge National Laboratory (ORNL) could help ethanol producers streamline this production process into a “one-pot method.” The breakthrough comes from a surprising source: a bacterium first found in the hot springs of Yellowstone National Park.

According to ORNL scientist Richard Giannone, the research is focused on “consolidated bioprocessing”—a method that will enable ethanol producers to “throw plant material into a pot with the microorganism and allow it to degrade the material and produce ethanol at the same time.”

The microorganism in question, Caldicellulosiruptor obsidiansis, breaks down organic material such as sticks and leaves in its natural environment. But it can also thrive at extremely high temperatures, leading ORNL scientists to believe it may be the key to the one-pot method of ethanol production.

Lauren Craig is a writer and consultant living in Seattle, WA. She holds an M.S. in International Development from Tulane University, and is co-founder of Sustainable Systems Integrators, LLC., an employee-owned solar energy design and installation firm in New Orleans, LA. She is also certified in PV design and installation by the North American Board of Certified Energy Practitioners (NABCEP).