The biogas project is the first sustainable project of its kind in the nation, capturing biogas generated during the sewage treatment process and selling it through a commercial gas pipeline.
“SAWS is constantly improving its operations to become more sustainable, and this project is a sound investment for our environment and our community,” said Robert R. Puente, SAWS President/CEO. “By reusing biogas instead of burning it off, we are helping protect the city’s air quality and developing a renewable energy resource.”
Methane gas is generated by biosolids during the sewage treatment process. Previously, SAWS burned off the gas using flares. With this 20-year partnership, Ameresco will treat and transfer at least 900,000 cubic feet of gas to a nearby commercial gas pipeline, where they will sell it on the open market. In return, SAWS ratepayers will receive a royalty on the sale of the gas, estimated at $200,000 a year, reducing the cost of SAWS operations and keeping rates affordable. SAWS is the first large wastewater utility to partner with a private sector company, Ameresco, to actively sell biogas in the United States.
“At Ameresco, we are driven to help our customers find renewable energy and energy efficiency solutions to achieve their goals,” said Michael T. Bakas, Ameresco’s senior vice president of renewable energy. “Whether those goals are a sustainable environment, reducing costs or reusing a resource, our energy engineers, project managers and plant specialists can make these goals a reality. Ameresco is proud to be a part of this team and groundbreaking project.”
With the addition of the biogas facility, SAWS is recycling and reusing almost all of the waste coming into Dos Rios through its “recycling trifecta.” Biosolids are also reused to generate compost, which is used in landscaping, gardening and agriculture to improve soil quality. Finally, the third part of the trifecta is recycled water. About 115 million gallons a day of high-quality recycled water are used for the Riverwalk, golf courses, parks, and commercial and industrial customers as well as in the upper San Antonio River and Salado Creek.