Saturday, May 13th was a pretty big day for renewable energy in the state of California. The right mix of sun, wind, and reservoirs at hydroelectric plants full from winter rains led to a record 67.2 percent of all power produced on the portion of the grid controlled by the California Independent System Operator (CAISO) coming from renewable sources. That percentage does not include hydroelectric power, but when factored in, hydroelectric sources bumped the number north of eighty percent.
On Tuesday, May 16th, the state also set a record for power generated from wind, producing 4,985 megawatts, or enough to power 760 homes at a given moment.
It’s important to stress that these numbers only cover roughly 80 percent of the grid in California. However, these numbers don’t include customer-sited solar, so the total percentage of renewable energy may actually be higher.
Hydroelectric power, which took a backseat during California’s long and severe drought, is bouncing back this year after heavy winter rains. Reservoirs in Northern California are at the highest levels in decades, and hydroelectric producers project that up to 21 percent of all power produced on the grid will come from hydroelectric sources. That would be the highest percentage since 2011, the last wet winter.
While not every year will provide torrents of rain to fill hydroelectric dams, the ability of the grid to take advantage of the surge in renewables is heartening. Sunny days, windy days, and rainy years are not completely predictable, but the electric grid needs to be ready and able to take energy from renewable sources and transmit them to consumers.