Turning sewage sludge into gasoline

To help Israel become a little less dependent on fossil fuel imports, engineers are looking in the sewer.

Michael Kanellos Staff Writer, CNET News.com
Michael Kanellos is editor at large at CNET News.com, where he covers hardware, research and development, start-ups and the tech industry overseas.
Michael Kanellos
3 min read
TEL AVIV, Israel--BioPetrol gets the award for finding the most novel way to get gas for cars.

The company is experimenting with a method of extracting oil out of sewage sludge, Amit Mor, CEO of Israeli investing and consulting firm Eco Energy, said in an interview. Mor, who advises BioPetrol, 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."

A ton of high-quality sludge can produce about 30 kilograms, or 66 pounds, of such oil, Mor said. The process can also convert pulp, agricultural waste, plastics and tires into oil.

Although Israel found a fairly sizable natural-gas field off its coast in 1999, the country relies on exports of oil and coal to keep the lights on. Getting energy out of sludge potentially could help alleviate the problem. The energy could be sold or, on a more practical level, used to keep things running in the cities where it is harvested.

In the United States, Microgy is building a facility in Texas that will convert manure from 10,000 dairy cows into natural gas that will be sold through conventional pipelines. Microgy's system breaks down manure with microbes. Other companies are trying to improve the process of making ethanol from vegetable matter.

BioPetrol does not use microbes, Mor said. It also does not produce ethanol; its process would yield standard hydrocarbon fuels. Instead, the company first dries the sludge and then combines the dried matter with proprietary catalysts and heat.

The process is conceptually similar, to some degree, to how some companies extract oil from shale, Mor said.

"The end result is the on-site reduction of dry sludge volume from 100 percent to 5 percent," according to an information sheet hosted by the Israeli Industry Center for R&D.

The idea first came from Ari Sofer, an expert in sewage who operated facilities in the United States and Israel. Typically, people try to chemically convert sludge into fertilizer. "That gave him the idea," Mor said.

BioPetrol got its start through Israel's incubator program, sponsored by the Office of the Chief Scientist (click here for PDF), which gives selected entrepreneurs $400,000, on average, over a two-year period to help them go from the concept stage to becoming a start-up with a business plan and, in most cases, a prototype.

After two years, these companies are expected to find their own investors, said Rina Pridor, who runs Israel's incubator program. The government does not retain an equity stake in these incubator companies, but the start-ups, if they survive, are expected to pay back the grant with interest.

Some Israeli venture capitalists grumble about the incubator program, claiming that it supports companies that can't or shouldn't get funded, but Pridor has numbers on her side. Companies that emerged from their two-year stints in 2005 have since received a collective $75 million in venture capital backing.

"We come in when private money won't touch them," she said.

BioPetrol is currently trying to raise $1 million to build a prototype facility, Mor said.