Living Batteries

Using sugars, sludge, and the sea floor, can bacteria power the next green-energy alternative? BY JACK LUCENTINI When Bruce Rittmann got a $100,000 NASA grant two years ago to find ways for converting human excrement and other organic waste into electricity in spacecraft, he prepared to reach for the stars.

When the space agency cut research funding, his ambitions became a bit more grounded. Using private-sector funds, Rittmann, a professor and director of the Center for Environmental Biotechnology at Arizona State University's Biodesign Institute, is now working to convert sewage and other organic matter to electricity here on Earth. He doesn't mind the shift in focus for work that he says could "transform the world."

His experience is emblematic of the halting yet determined...