According to Wired News…

Researchers at Penn State University say they’ve developed a way to use bacteria to extract hydrogen from almost any biodegradable organic substance, from grass clippings to wastewater. Hydrogen is often touted as a virtually limitless source of clean energy, but its ecological benefits have been minimal because it is often produced using natural gas in a process that releases carbon dioxide — a problem the new method seems to solve. The discovery, published Monday in Proceedings of the National Academy of Sciences, holds great promise for advancing hydrogen as a viable sustainable fuel because, the researchers say, it uses existing technology and can be put to use immediately.

More on this as it develops.