Case Study: City of Missoula offsets over 20% of wastewater plant electricity use with Ameresco solar

Ameresco and City of Missoula Announce Completion of New Wastewater Treatment Plant Solar Pv Array

The City of Missoula wanted to advance its carbon neutrality goal by 2025 while reducing electricity use and emissions at its wastewater treatment plant. To do this, the city sought a solar solution that could work under Montana’s legal and site constraints, including buried concrete and rebar, and still maximize on-site generation without exporting power to the grid. Ameresco proposed a behind-the-meter solar energy agreement for the facility.

Ameresco designed, built, owns, operates, and maintains a 545 kW DC non-export solar PV array using geo-ballasted, non-penetrating ground-mount racking to fit the unique site conditions. The system is expected to produce more than 700,000 kWh annually and offset over 20% of the plant’s electricity consumption, delivering meaningful cost savings and supporting the City of Missoula’s sustainability goals with $0 upfront cost and a 25-year project term.

City of Missoula

Ross Mollenhauer

Engineering Manager