Last week a NPR affiliate, WFDD, out of Winston, Salem, North Carolina did a series on alternative fuels. For their piece on cellulosic ethanol, WFDD made an interview with Novozymes’ Garrett Screws, Chris Veit, and Larry Peckous.
According to Veit, the challenge with breaking down cellulose starts with nature. “[Cellulose is] what makes the plant withstand nature. It’s what makes the plant so difficult to degrade over time.”
To break a cellulosic structure down into simple sugars it takes a lot more enzymes, which in turn makes the process more expensive. Three years ago the enzymes used to make just a gallon of cellulosic ethanol cost $2.00.
Around that time, Novozymes received a grant from the National Renewable Energy Laboratory (NREL) and has since reduced the cost of the enzymes process thirty fold, down to about 14 cents a gallon.
“We’ve worked really hard on solving the enzyme part of the puzzle, but that’s just a piece of the value chain,” Garrett Screws said. “Right now there isn’t a machine to drive through the field and collect the corn stover.”
The challenge is in discovering someone to invent that machine and integrate the other components of the puzzle. NREL is preparing to fund a demonstration refinery to demonstrate the technology and improve the economics.
To listen to the entire interview, visit www.wfdd.org. Click on the news link off the home page, and then on the series link "The Drive Towards Alternative Fuels."