Submitted by Energy Answers Blog

Researchers at the University of Texas found that biogas (mainly methane) from livestock manure could produce about 2.4% of U.S. electricity needs while reducing greenhouse gas emmissions. A useful fertilizer would be left as a byproduct. Currently, a large portion of livestock manure is wasted or even produces environmental contamination.
Cow power: the energy and emissions benefits of converting manure to biogas