The Little Weed That Could
Newsweek International
Sept. 6-13 issue - When Americans settled the Western prairies in the 1800s, they came across fields of swaying switch grass four meters high. Since the early 1990s the U.S. Department of Energy has been looking into whether this humble but hardy plant might develop into a replacement for fossil fuels. Scientists have long known how to turn plants into ethanol, but they hadn't gotten the hang of doing it cheaply. Now researchers are discovering inexpensive ways of making not only ethanol but other petroleum-based products, like plastic, from plants.
One of the most promising innovations is a genetically engineered strain of switch grass that might be a source of biodegradable plastics. With funding from the U.S. Department of Agriculture and the DOE, Metabolix, a research firm in Cambridge, Massachusetts, has inserted into the switch grass genes from a bacterium that naturally forms PHB—a chemical precursor to plastic. The idea is to eventually harvest the grass and feed it into "a biological version of an oil refinery," says Ray Miller, a researcher at Du Pont. Such an "integrated biorefinery" could take in switch grass, as well as plants like corn, and churn out ethanol, biodegradable plastics and other petrochemical substitutes. Du Pont, which has received about $20 million from the DOE for the project, hopes to open its first pilot integrated biorefinery in three years. Rather than being paid for not growing food, farmers may one day grow grass for fuel.
—Michael Hastings
© 2004 Newsweek, Inc.
URL: http://www.msnbc.msn.com/id/5852746/site/newsweek/
Spinach Power
Newsweek International
Sept. 6-13 issue - Some scientists won't stop playing with their vegetables. Researchers at MIT think spinach, to be exact, may hold the key to a new, flexible solar panel that could one day be woven into clothes or coat electronic gadgets. Taking a cue from plants, which capture the sun's energy, Marc Baldo and his team took spinach cells and extracted proteins that play a role in photosynthesis. They mixed the proteins with a soaplike substance to keep them in place and then sandwiched the goo between thin layers of metal. When light shines on the device, the proteins give up electrons, producing a current. The spinach proteins give Baldo's cells a lightness and flexibility that conventional solar cells can't match.
To make the biosolar cells cheaper and more efficient, the MIT team is trying to squeeze more proteins on a one- by one-millimeter cell. Another limitation: the proteins have a shelf life of only three weeks. The U.S. military, which funds the work, wants to use biosolar cells in tiny spy craft. Someday they might come in handy for iPods too.
—Kathryn Williams
© 2004 Newsweek, Inc.
URL: http://www.msnbc.msn.com/id/5852745/site/newsweek/