Approximately 1,200 wastewater treatment plants in the U.S. are capturing and using biogas produced during wastewater solids treatment, accounting for nearly half of the nation’s roughly 2,600 biogas facilities, according to new data from the American Biogas Council.

Together, the facilities capture more than 100 billion cubic feet of biogas annually, the council reported. Most plants use the methane-rich gas generated through anaerobic digestion to produce electricity or heat on-site, helping offset energy purchases and operating costs.

The American Biogas Council estimates that approximately 3,800 additional wastewater treatment plants have sufficient flows to make biogas capture viable. If those facilities adopted biogas recovery systems, annual production could increase to about 172 billion cubic feet, according to the organization.

Anaerobic digestion allows wastewater facilities to reduce the volume of biosolids while producing biogas that can be used as a renewable energy source. A smaller share of facilities, approximately 4% of those currently capturing biogas, upgrade the gas to renewable natural gas for use as a substitute for conventional natural gas.

The findings highlight the potential for wastewater utilities to further position treatment facilities as resource recovery and energy-producing assets, particularly as utilities face rising electricity costs and growing demand for reliable power.