Thanks to sunny weather and continuous addition of new facilities, output and share of PV power in California has marked a milestone recently.

Share of PV power topped 49.95% in March 4 in California, breaking the previous record of 47.2% on May 14, 2017, according to CAISO, an independent grid operator in the state. Anne Gonzales of CAISO reported that PV power output exceeded 9,400 MW on March 4, a sunny weekend when power need was not high and minimum load stood at only 18,800 MW.  

The record was broken again on the following day, on March 5, when PV power output reached 10,411 MW at 10:18 a.m., 500 MW higher than the previous record of 9,913 MW on June 17, 2017.

PV power has thrived in California, thanks to its sunny weather, similar to southern Australia, plus policy support. Consisting of large-scale PV power stations, rooftop PV power generators, and concentrated PV power facilities, the state's PV power industry has been constantly expanding its output, even selling its excess power to neighboring states. California is expected to have renewable energy supply to half of its power need by 2030 and 100% by 2050.

The industry also owes its thriving development to strong policy support, such as Renewables Portfolio Standard (RPS) which stipulates that renewable energy must account for 33% of total energy procurement by 2020, prompting many communities to embrace choice aggregation programs (CCA) for PV power investments.

The mushrooming PV power facilities, however, have overstrained existing power infrastructure, such as the management and capacity of grids. CAISO and other ISOs (independent system operators) have been endeavoring to cut energy curtailment and energy waste, in order to maximize utilization of renewable energy, including improvement of energy storage system and better monitoring of energy need and consumption time.

Moreover, CAISO has been dedicated to the development of large-scale energy imbalance market, featuring cross-latitude and -region real-time power-market integration, in order to lower fluctuation of renewable-energy supply and demand. CAISO brought US$34 million of income to the western region of the U.S. in Q4 2017, generating 18,060 MWh of power, which cut CO2 emission by 7,730 metric tons, according to its report.

(Article by Daisy Chuang; photo courtesy of California ISO Twitter)