Duluth awarded $700,000 grant to study using wastewater to heat buildings

DULUTH — Duluth has been awarded a $700,000 grant by the Department of Energy to develop a geothermal district heating system using waste from Western Lake Superior Sanitary District to heat buildings in the Lincoln Park neighborhood.

The system would ideally meet all of the heating loads of properties in the area, according to the project proposal. The city is one of 11 communities to get similar funding to create a design that could potentially be picked by the Department of Energy to receive up to 90% of the implementation costs.

"We hope that the project will offer a way to both decarbonize hundreds of buildings using geothermal energy investments, and also stabilize heating fuel prices into the future," Duluth Mayor Emily Larson said Tuesday afternoon at a news conference in the neighborhood's Pocket Park on West Superior Street.

Ken Smith, CEO of Ever-Green Energy, said this technology works by using heat pumps to recover wasted thermal energy — a concept that has been tested in China, Finland and Sweden, but not yet in the United States. The St. Paul company also worked with the city to swap out steam heat for a closed-loop hot water system during the reconstruction of East Superior Street. Part of the upcoming planning process, Smith said, would require figuring out how to tie these two different neighborhood systems together.

Mindy Granley, sustainability officer for the city, said the system moves heat around instead of burning fossil fuels. Over the next year, a team will determine the economical and technical feasibility of the process.

The other projects selected by the Department of Energy — including geothermal plans in areas ranging from Ann Arbor, Mich., to Chicago, to Middlebury, Vt. — are part of the federal government's Justice40 Initiative, a push toward 40% of federal climate investments benefitting disadvantaged communities by 2025.

Lincoln Park, located near Interstate 35, has been redeveloped with a craft district aesthetic in the past decade. It has a 39% poverty rate, almost double the city's overall number. It was described in the grant application process as a neighborhood with high energy burdens and negative environmental indicators, including poor air quality. Residents are in the lowest half-percent for life expectancies, according to Jodi Slick, founder of Ecolibrium3 — a Lincoln Park-based nonprofit that works toward sustainability and equity.

In 2022, the city was awarded a $25 million federal grant for West Superior Street construction through the Rebuilding American Infrastructure with Sustainability and Equity program. The work on 1.65 miles of the neighborhood's main road — and it's more than century-old underground utilities — could coincide with the geothermal project.

Larson said the city has already reduced greenhouse gas emissions 30% since 2016.

"However, and as important as all of that is, we also want to reduce our operating emissions and we know we need to work with the community at much larger scales to find clean energy," Larson said.