‘Virtual power plants’ would store renewable energy in batteries by day and redistribute it when demand surges after sunset
As California ramps up renewable energy, utility companies are looking to batteries to solve a supply-demand mismatch, storing excess solar power and feeding it as needed to the grid. Here, a solar farm and wind turbines in Palm Springs Calif. Photo: Moment Editorial/Getty Images
California utilities including PG&E Corp., Edison International and Sempra Energyare testing new ways to network solar panels, battery storage, two-way communication devices and software to create “virtual power plants” that manage green power and feed it into the power grid as needed.
The Golden State is ramping up renewable energy as it pledges to be a bulwark against the Trump administration’s pro-fossil fuel policies. But first, it has to figure out what to do with all the excess power it generates when the sun is shining and the wind is blowing.
California’s solar farms create so much power during daylight hours that they often drive real-time wholesale prices in the state to zero. Meanwhile, the need for electricity can spike after sunset, sometimes sending real-time prices as high as $1,000 a megawatt-hour.
Utility companies are looking to correct that supply-demand mismatch and ease the strain on the electric grid as California considers retiring its last nuclear plant in 2025 while nearly doubling the power it gets from renewable sources to 50% by 2030.
Last month, power company AES Corp. flipped the switch on a bank of 400,000 lithium-ion batteries it installed in Escondido, Calif., for Sempra Energy. Sempra’s San Diego utility plans to use the batteries, made by Samsung SDI Co. Ltd., to smooth out power flows on its grid.