Cellulosic Scale-Up

IN FEBRUARY 2007, the Department of Energy selected six cellulosic ethanol projects to receive up to $385 million in grants. Authorized by the Energy Policy Act of 2005, the funding was part of an effort by the Bush Administration to end the U.S.’s “addiction to oil” and enhance the nation’s energy security.

The money was intended to further two of President George W. Bush’s goals: to make ethanol out of nonfood biomass, including billions of pounds of agricultural waste, at a cost competitive with gasoline by 2012 and to increase the use of renewable and alternative fuels to 35 billion gal per year by 2017. In all, more than $1.2 billion was to be invested in the six biorefineries.

Two years later, none of the projects has been built, although one is under construction. Two were canceled right out of the gate. Hitches in the plans have turned up in numerous places. From securing feedstock to financing construction to finding a ready market, the experiences of the awardees illustrate that the nascent cellulosic ethanol industry faces several daunting hurdles.

…POTHOLES ABOUND on the road to commercializing cellulosic ethanol. Iogen’s Chepeka says her company recognizes six discrete steps. The first task is to show successful operation of a demonstration-scale plant. Then the company must select a commercial plant site and sign contracts for feedstocks. The firm needs to be able to purchase the land and get government support to help share the financial risk. Finally, the company needs to attract enough government and private investment to finance construction of the actual ethanol-producing plant.

It is not yet clear if any of the contenders have found a workable formula for the next stages: selecting a commercial plant site and ensuring ready supplies of feedstock at a reasonable cost. According to Gene Petersen, project manager at DOE’s Golden, Colo., field office, even seemingly free feedstock, such as agricultural waste, isn’t really free. “The feedstock budget has gone up by a factor of 10,” he says, because companies’ plans did not account for the full cost of the supply chain, including getting feedstock to the plant site. Particularly problematic, Petersen says, is transporting lightweight corn stover in a cost-effective manner.

Chemical & Engineering News