The United States Department of Energy (DOE) recently announced that it would provide up to $383 million to support six biorefineries that will extract fuel from materials such as wheat straw, wood chips, grass clippings, and even orange peels. The projects are meant to help achieve President Bush's goal of using 35 billion gallons a year of ethanol and other alternative fuels by 2017.

Each of the six projects takes a different approach. Some use corn stalks and cobs as fuel, others use rice husks, wood chips or clippings from municipal waste. The technologies range from ripping up the woody cellulose with enzymes, to chewing it up with acids, to gasifying it. The resulting sugars or gas will be forged into ethanol. Some facilities will also produce other products such as ammonia or methanol.

The full article is available to subscribers of the journal Nature at http://www.nature.com/news/2007/070226/full/070226-15.html..