Aemetis buys Keyes, Calif. plant, plans 2G biofuels testing

By Susanne Retka Schill | July 10, 2012

Aemetis Inc. has acquired Cilion Inc. and its 55 MMgy ethanol plant in Keyes, Calif., with plans to continue operating the corn ethanol plant as it enters the next stage in its cellulosic ethanol development project.

Built by Cilion, the plant came online in 2008 and was operated just four months before closing. Aemetis, formerly AE Biofuels Inc., leased the plant in 2010. “We spent the better part of a year upgrading the facility and retrofitting some of the issues we found,” said Andy Foster, president and chief operating officer.  The plant has run continuously since April 2011. “It’s a very nice plant,” he said. “We’ve had over a year without a single down day. We have a team that can perform the various maintenance items on the fly.”

Foster said the purchase of the plant is the next step in the company’s development plans. “The goal is to continue producing ethanol and start the process of transforming this into a biorefininery,” he said. “We’re looking at biofuels as well as specialty chemicals.” Isoprene, a precursor for industrial products like synthetic rubber, flavorings and other chemicals, is one chemical of interest named on the company’s website.

The company will be using a $1.9 million matching grant from the California Energy Commission announced earlier this year to build a co-located pre-commercial cellulosic ethanol facility at Keyes to test the two technologies the company has acquired, as well as others. “The goal is to replace 15 to 20 percent of the corn and do it as an integrated facility, and not as a side by side,” Foster said.

In 2008, Aemetis built an integrated cellulose and starch ethanol demonstration facility in Butte, Mont., to optimize its “ambient temperature starch/cellulose hydrolysis” process. Last year the company acquired Zymetis Inc., developers of the Z-microbe, a patented organism that converts a variety of renewable feedstocks into renewable chemicals and biofuels, using a consolidated bioprocessing technology.

Foster said they are currently evaluating potential partnerships and will likely test other technologies for pretreatment as well as other developers’ enzymes and yeasts. The facility will run tests using a variety of feedstocks available in California’s Central Valley where the facility is located, including corn stover, cobs, wheat straw and even cotton gin waste.  

In addition to the California ethanol plant and cellulosic development project, Aemetis owns and operates a biorefinery on the east coast of India. Its subsidiary, Universal Biofuels Pvt. Ltd., can produce edible oil, up to 50 MMgy of biodiesel and pharmaceutical-grade glycerin.