Case Study: Granite Construction achieves $860K annual savings with Stem’s Athena energy storage

Granite Construction Achieves $860K Annual Savings with Stem

Granite Construction, a large diversified construction and materials firm, faced rising demand charges and shifting rate structures across its California sites. To gain flexibility to buy low‑cost energy and use stored power during peak times, Granite began deploying energy storage with Stem in 2018—selecting Stem for its Athena smart energy software and its ability to work with all three major investor‑owned utilities.

Stem installed a 4.6 MW / 8.9 MWh storage portfolio across five sites and used its Athena AI‑driven predictive analytics to automatically dispatch batteries during peak demand and qualify Granite for PG&E’s Option S tariff. The Stem solution delivered $860,000 in utility bill savings across the five sites in 2020 (including $85,000 at the French Camp location), with additional installations in progress.

Granite Construction

Chris Herne

Corporate Plant Equipment Manager