According to new estimates from the federal Energy Information Administration (EIA), utility-scale solar generation in the territory of the California Independent System Operator (CAISO) accounted for almost 40 percent of net grid power produced during the hours of 11:00 a.m. to 2:00 p.m on March 11, 2017.
CAISO’s achievement is a reflection of the 50 percent growth rate of utility-scale solar farms in California in 2016. And the large-scale production of electricity has quite often driven wholesale electricity prices on the power exchange during late winter and early spring daylight hours to low and sometimes negative prices.
This does not mean that on those occasions, consumers don’t have to pay for their electricity. Californians continue to pay retail electricity prices, said to be among the highest in the nation, but not as high as prices in Alaska and Hawaii.
Total solar capacity in California includes both utility-scale solar photovoltaic (PV) systems as well as a few solar thermal plants. The use of solar power has grown from less than 1 GW in 2007 to nearly 14 GW by the end of 2016. Solar power generation also follows seasonal and daily sunlight patterns.
Interestingly, California’s above average rain and snowfall this past winter have also affected the wholesale price of electricity on the grid due to increased power generation from hydroelectric plants, according to Clean Technica.
The electrical grid and its operation are not as simple as many people believe. For example, in California, grid operators have been concerned over the effects of an increase in solar generation on the operations of the grid for several years. One of the issues they are studying how to integrate large amounts of solar into the power market.
