Bio-Petrol

Bio-Petrol is experimenting with a method of extracting oil out of sewage sludge, according to Amit Mor, CEO of Israeli investing and consulting firm Eco Energy. Mor, pictured here, who advises Bio-Petrol, said the extracted oil could be converted into gasoline and natural gas.

"Sludge is a major problem in the world. Cities pay $50 a ton or more to get rid of it," he said. "And it's good-quality light oil."

The company got its start in one of the government-sponsored incubators and is currently trying to raise $1 million, Mor said.