Scientists are developing technology that would turn raw sewage into an energy source, according to a report being published Monday in the American Chemical Society journal Environmental Science & Technology.

Researchers at Pennsylvania State University have tested a microbial fuel cell, similar to a hydrogen fuel cell, that captures electrons naturally released by bacteria as they digest organic matter and converts them into electric current, instead of having it oxidize. So far, scientists have generated 76 milliwatts per square yard by converting biodegradable wastewater, said Bruce Logan, Penn State's Kappe Professor of Environmental Engineering.

While 76 milliwatts is not a lot of electricity -- common light bulbs use 100 watts of energy -- Logan said he saw a system in which wastewater treatment plants would power themselves with this technology. Wastewater treatment now consumes 5 percent of American energy production, he added.

Wastewater from 100,000 people could yield 2.3 megawatts of power, he said, enough to power 1,500 homes.