Arizona Public Service Electric Company surpasses hits major solar energy capacity milestone

The Arizona Public Service Electric Company (APS) recently surpassed one gigawatt (GW) of solar energy capacity, becoming the only utility outside of California to reach such a milestone and enabling the company to meet the partial daytime needs of approximately 250,000 Arizona households.

APS’s total investment in solar energy is approximately $2 billion, with a solar portfolio split between 551 megawatts (MW) from rooftop systems and 449 MW from grid-scale projects.

“APS customers benefit from the fact that when you include energy from APS’s other renewable energy sources — wind, geothermal, biomass and biogas – and the Palo Verde Nuclear Generating Station, nearly half of all the power on APS’s system is carbon-free,” APS Vice President of Resource Management Tammy McLeod said. “A cleaner energy mix is a top priority for us, with solar playing an important role.”

APS sources grid-scale solar generation from a number of APS-owned systems and power purchase agreements. APS owns and runs nine solar plants throughout Arizona through the AZ Sun Program. The plants offer 170 MW of capacity and were built using plans employing independent solar developers, contractors and equipment providers. The remaining grid-scale solar is obtained from independently owned Arizona power plants with long-term agreements to sell power to APS.

A majority of the power sourced from rooftop solar is obtained from systems owned by homeowners or leasing companies. APS owns 10 megawatts of rooftop solar, and the systems are strategically placed on customer homes. The placement allows APC to study how solar and other advanced technologies, including smart inverters and battery storage, could improve service.