Case Study: Massachusetts Water Resources Authority achieves net-zero emissions progress and utility bill savings with Stem’s Athena energy storage solution

Leveraging Critical Facilities to Advance Net-Zero Emissions Goals

The Massachusetts Water Resources Authority (MWRA), the public agency supplying water and sewer services to more than 3 million people in eastern and central Massachusetts, faced resilience and redundancy challenges plus high utility bills and demand charges—especially at a large pumping station. MWRA engaged Stem to deploy battery energy storage (1 MWh of standalone, behind‑the‑meter systems at a pump house and an administrative building) and use Stem’s Athena smart energy software to shift loads and optimize utility costs.

Stem implemented its 1 MWh storage systems and Athena platform to move loads to off‑peak hours, perform automatic demand response discharges, monitor demand and interface with the utility, and enable wholesale market revenues. The systems reached commercial operation in January 2021, are coordinated with Eversource, and—according to MWRA—have reduced carbon footprint while delivering attractive cost savings and improved onsite resilience under Stem’s management.

Massachusetts Water Resources Authority

Fred Laskey

Executive Director