San Antonio, Texas will be the first city in the United States to harvest methane gas from human waste on a commercial scale and turn it into clean-burning natural gas.
San Antonio’s Business Journal said the city signed a 20-year lease with Ameresco Inc., who will convert the city’s “biosolids” — sewage — into natural gas.
“The citizens of San Antonio produce about 140,000 tons of biosolids each year,” said Steve Clouse, chief operating officer of San Antonio’s water system.
Methane gas, the main byproduct of human and organic waste, is a major component of natural gas that is burned in power plants, furnaces and combustion generators.
The city’s biogas will be prepared in a processing plant built in San Antonio and then sold on the open market, making it the first city to do large-scale conversion of methane gas to fuel for generating power.
San Antonio’s utility system will get a 12 percent royalty from the sales.
The city already sells most of its biosolid waste to composters.
“SAWS agrees to sell methane gas from treatment plant”
San Antonio Business Journal, September 10, 2008