Sewer Waste: San Antonio’s Newest Energy Source

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Courtesy of the San Antonio Convention & Visitors Bureau
San Antonio, Texas

The city of San Antonio reached an agreement last week to collect and sell the biogas emitted by its municipal sewer system. Ameresco, a Massachusetts energy solutions company, will buy the gas, which contains 60 percent methane, process it and sell it to be included in the natural gas pipelines.

With the current waste, San Antonio can produce an average of 1.5 million cubic feet of gas a day, or 1,250 tanker trucks each day, according to city officials. The city will receive between $200,000 and $250,000 a year as payment, reports local media.

The city of San Antonio has been in the forefront of sewer water recycling. Currently 80 percent of the biosolids from the sewer system are used for compost. The city also sells recycled water to manufacturers and landscapers. The collection of biogas will add to the city’s sewer water recycling program.

This renewable source of energy won’t be ready for at least another year and half, as Ameresco will have to build the facilities to process and transport the gas to the pipelines.

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