Poet reduces cost of cellulosic ethanol production

By Erin Voegele | November 11, 2009
Report posted Nov. 20, 2009, at 11:54 a.m. CST

Poet LLC recently announced it has reduced the per-gallon cost of cellulosic ethanol production by $1.78 during the first year of operation at its Scotland, S.D.-based pilot-scale production facility. According to the company, the cost reductions achieved during their first year of operating the pilot plant have exceeded expectations. Reductions in energy usage, enzyme costs, raw material requirements and capital expenses reduced the per-gallon cost of cellulosic ethanol from $4.13 to $2.35 during this time. Poet's goal is to achieve a per-gallon cost below $2 before start-up of their planned commercial-scale facility.

The pilot facility in Scotland first began producing ethanol on Nov. 18, 2008. To date, the facility has produced approximately 20,000 gallons of cellulosic ethanol. According to information provided by Mark Stowers, Poet's senior vice president of science and technology, the pilot facility was able to demonstrate lab-scale performance in its first 30 days of operation. "I think our pilot demonstration has been hugely successful and we are at the stage where we are passing our technology package over to our design and construction colleagues to begin the process of looking at a commercial-scale operation in Emmetsburg," he said.

Poet plans to construct a 25 MMgy commercial-scale cellulosic ethanol plant in Emmetsburg, Iowa, which is referred to as Project Liberty. "Poet has been working on cellulosic ethanol for close to a decade and there were some days that I wasn't sure we'd be successful," Poet CEO Jeff Broin said. "While we still have some challenges ahead, I can say unequivocably that Project Liberty will be commercially viable by the time we start up the plant."

Broin said he is pleased with the progress made at the pilot plant during its first year of operations. The facility achieved cost reductions in several areas:

  • Chemical raw materials required in the process were reduced, resulting in cost savings of 20 cents per gallon

  • Energy used in the pretreatment process was reduced by more than 50 percent

  • Alternative energy technology employed by the facility demonstrated the ability to provide all the energy needed to operate the cellulosic pilot facility as well as provide approximately 80 percent of the energy needs of the adjacent corn ethanol facility

  • Enzyme costs have been cut in half, and are expected to decline further before startup of Project Liberty

  • Through continuous optimization of the process, entire unit operations were eliminated, reducing the overall capital cost by more than 40 percent

    "There are still several opportunities to make the process more efficient, particularly in fermentation," Stowers said. "Additionally, our enzyme partners have committed to significant additional cost reductions. But significant gains can also be made once we start up the commercial facility and Poet uses its 20 plus-year history in biorefining to drive cost reductions and efficiency improvements in the process."
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