US utility Pacific Gas and Electric (PG&E) has announced it has surpassed 1 million customers with solar systems connected to its grid, the most of any utility in the United States, marking a defining moment for California’s customer-led clean energy transition. The company says the achievement reflects decades of policy support, customer adoption and grid upgrades, with solar moving from a niche technology in the 1990s to a central part of the state’s power system.
The growth has accelerated sharply in recent years. PG&E says more than half a million new solar interconnections were added between 2020 and 2025, and that it has seen more than 70,000 new solar installations a year over the past two years. Across Northern and Central California, the company says households, farms, schools and businesses are using solar to cut emissions, improve resilience and reshape how electricity is produced and consumed.
The milestone also points to a broader shift in how utilities think about distributed energy. PG&E says its focus is no longer just on connecting rooftop systems, but on adapting the grid for two-way power flows through automation, forecasting, streamlined interconnection and more battery storage. That work is tied to the rise of virtual power plants, which allow aggregated customer batteries to act together as a flexible resource when demand spikes or local constraints emerge.
PG&E highlighted a 2025 test in which customer batteries delivered 535 MW to the grid for two hours, enough to power hundreds of thousands of homes during the evening peak. The company says such programmes show how solar and storage can become part of grid operations rather than sitting at the edge of the system.
PG&E also signalled support for newer customer technologies, including plug-in solar and storage, but said any device exporting power must meet safety and grid standards. The company framed the milestone as evidence that California’s grid is becoming more distributed, more digital and more participatory.
