So far, only a handful of utilities have a gigawatt of solar power in their electric grid and today (Oct. 7) that handful got a little larger as Arizona’s APS announced that it surpassed the threshold. In fact, it’s the first time a utility outside of California has surpassed that level of solar. What’s more, the company said its solar power is almost evenly divided between distributed resources like rooftop solar and utility-scale solar.
APS said it has 551 megawatts of rooftop solar installations and 499 megawatts of utility-scale solar in its portfolio. It said it’s invested about $2 billion in solar throughout its service area, where it provides power for 2.7 million people. The company said the solar in its network can provide power the partial daytime needs of 250,000 of its customers.
“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,” said Tammy McLeod, APS Vice President of Resource Management. “A cleaner energy mix is a top priority for us, with solar playing an important role.”
It’s likely that only California’s Pacific Gas & Electric and (PG&E) Southern California Electric (SCE) are the only utilities to surpass that threshold. After all, SCE ranked highest in the Smart Electric Power Alliance’s (SEPA’s) annual solar market survey in 2016, installing 1.3 gigawatts os solar in 2015 alone, while PG&E ranked second installing 787 megawatts in 2015.
APS owns 170 megawatts of utility-scale solar power in its grid. The rest of it comes from power purchase agreements with independently owned power plants across Arizona.
The majority of rooftop solar power in its network is owned by homeowners or leasing companies. The utility does have a program under which it owns the solar panels on rooftops, however, and said it has 10 megawatts under that program. That program also is designed to help the utility research how solar and other technologies, including smart inverters and battery storage, impact the ability of the electric grid in the state.
While the solar power in APS’ network is still a fraction of the overall electricity that the company provides its customers—less than 10 percent—it’s still significant for a US utility. With more rooftop solar installed in its network, which tends to have higher costs than utility-scale solar, APS also has struggled with how to reduce the amount of new rooftop solar coming into its grid. Most recently it filed to end net-metering for its solar-using customers.Tweet