Sunday, February 17, 2008

Khosla Bullish on Biofuels

Vinod Khosla of Khosla Ventures (and founder of Sun Microsystems) is bullish on biofuels. For a recent essay in Wired, he visited a Colorado-based biofuels company (and investment) called Kergy:

Kergy’s machine is special because it makes cellulosic ethanol through anaerobic thermal conversion rather than through fermentation or acid hydrolysis. It does not need organisms or enzymes to do its work. Biomass is heated in an oxygen-free environment to produce carbon monoxide and hydrogen. Once that happens, “the world is your oyster,” says Bud Klepper, the engineer who invented this device. The carbon monoxide and hydrogen are then reconstituted into various alcohols – like ethanol. Better still, fermentation and acid hydrol­ysis can take days to occur, but thermal conversion breaks down organic matter and converts it to ethanol in minutes.

And here’s the really exciting part: Because all organic matter contains carbon, Klepper can make ethanol out of cellulose or any form of organic matter. This means the usual suspects such as corn, switchgrass, sugarcane, and miscanthus but also any waste product such as wood chips, paper pulp, cow manure, and even human waste. Municipal sewage has been tested already, as has hog manure.

Some studies have recently come out negative on biofuels, saying they're too expensive, use too much land, too much CO2. Are biofuels a small or large part of a 21st century clean energy system?

1 comment:

Maria Surma Manka said...

PS - Some researchers have responded to the recent studies that argue against biofuels.

From biofuels expert David Morris at the Institute for Local Self-Reliance:

and here from the Argonne National Laboratory and the U.S. Dept of Energy (beware - very wonky):