What used to be flared off as waste is now powering a city. Duluth’s newly upgraded wastewater treatment plant, Resource Renew, is turning sewage into savings by capturing and converting biogas into clean electricity, marking a major leap in the energy-from-waste movement.
The $19 million project uses anaerobic digesters to transform organic sludge into biogas, which now powers three new engine generators. Together, they produce 1.5 megawatts of electricity, supplying 60% of the plant’s power and saving $100,000 per month on electric bills.
But the innovation doesn’t stop there. With support from a $700,000 federal grant, local nonprofit Ecolibrium3 is working with the city to harness the 90°F waste heat discharged daily into the Saint Louis River. A proposed district heating system could soon warm hundreds of low-income homes in the surrounding Lincoln Park neighborhood, turning an environmental justice burden into a clean energy asset.
“It’s a milestone in our energy reduction efforts,” said Carrie Clement, incoming executive director of Resource Renew, which serves Duluth, Cloquet, and other communities across a 530-square-mile area.
While Minnesota is home to 1,600 wastewater treatment plants, only a fraction currently capture biogas for energy. Projects like this, which are backed by data from the American Biogas Council, highlight the untapped potential nationwide. With over 1,200 WWTPs already capturing biogas and thousands more capable of doing so, the momentum is growing.
Duluth’s project is a powerful example: cut greenhouse gases, power essential infrastructure, and help communities thrive—all from what we flush away.
For Diamond Scientific, this trend underscores the rising need for precision gas monitoring, leak detection, and system optimization technologies. As more facilities seek to recover energy and reduce methane emissions, reliable biogas instrumentation becomes mission-critical.
