Stem, Regis Energy Partners, and Excelsior Energy Capital Announce $400M Portfolio of Energy Storage Projects in Texas

Stem, Inc. (NYSE: STEM), a global leader in AI-driven clean energy solutions and services, today announced four 9.9 megawatts (MW) standalone energy storage projects in Texas with REX Storage Holdings, LLC (REX), an independent power producer focused on standalone battery energy storage systems (BESS) for ERCOT power customers. REX is a joint venture between Regis Energy Partners LP, an independent developer, owner, and operator of energy storage systems, and Excelsior Energy Capital (EEC), a leading investment fund focused on renewable power generation. The projects represent the first of a $400M equity commitment by REX to acquire additional construction-ready projects from Regis’ development pipeline within the Electric Reliability Council of Texas (ERCOT)’s territory, power supplier to more than 26 million customers representing approximately 90 percent of the state's electric load.

Regis is overseeing the projects’ development while Stem is supplying the battery hardware, Athena, its leading AI clean energy management platform, and services over each project’s operating life. Stem’s proven expertise across multiple jurisdictions and depth of market knowledge were instrumental in understanding the complexities of the evolving ERCOT marketplace to position the projects for short- and long-term success. As a result, the projects are poised for optimized returns over their lifetime. The initial four energy storage systems are currently under construction and are planned to come online in 2023.

John Carrington, CEO of Stem, commented, “The energy storage market in Texas represents a significant growth opportunity for leading renewable energy investors like Excelsior who recognize the rich merchant revenue opportunities in the ERCOT market. Stem has spent the past decade helping project developers and independent power producers (IPPs) get projects to commission and drive higher economic output with our AI-driven Athena platform, energy consulting and support services, and ability to manage and optimize projects over time. We will continue to partner with regional developers like Regis to collectively help investors achieve their energy optimization goals in the region while accelerating the adoption of renewable assets.”