Powering Strong Communities

Calif. grid operator issues call for conservation with forecasted high temperatures

The California Independent System Operator (ISO) issued a call for voluntary electricity conservation, from 3 p.m. to 10 p.m. on Oct. 1.

“With high temperatures in the forecast, the power grid operator is predicting an increase in electricity demand, primarily from air conditioning use,” the grid operator said in issuing a Flex Alert on Sept. 30.

Energy reduction during a Flex Alert can prevent further emergency measures, including rotating power outages, it noted.

Reduced capacity, along with fire activity and heat, has led to a potential shortage of energy supply the evening of Oct. 1 in the state.

On the afternoon of Sept. 30, a Grid Alert was issued for a possible electricity shortage in the day-ahead market, for one hour beginning at 6 p.m on Oct. 1. and a Restricted Maintenance Operations (RMO) notice was issued for 6 a.m.to 10 p.m. on Oct. 1.

The Grid Alert will allow operators to call up demand response supply, while the RMO allows operators to call all available generation onto the system and bring back transmission that may be offline for planned maintenance.

“Consumers are urged to conserve electricity, especially during the late afternoon and early evening, when the grid is most stressed due to higher demand and solar energy production falling,” the grid operator said.

 Consumers are also being asked to turn off unnecessary lights, delay using major appliances until after 10 p.m., and set air conditioner thermostats to 78 degrees or higher.

Smoke from wildfires decreases solar generation in CAISO

In the first two weeks of September 2020, average solar-powered electricity generation in CAISO declined nearly 30% from the July 2020 average as wildfires burned across the state, the Energy Information Administration reported this week.

As of September 28, California wildfires have burned an estimated 3.6 million acres in 2020, an area about the size of Connecticut, it noted.

Wildfire smoke contains small, airborne particulate matter particles that are generally 2.5 micrometers or smaller (referred to as PM2.5)., which reduces the amount of sunlight that reaches the solar panels.

In July 2020, daily solar-powered electricity generation, which includes generation from solar photovoltaic and solar thermal electric generators, ranged from 104 gigawatt hours (GWh) to 119 GWh, averaging 113 GWh for the entire month.

Daily solar-powered generation began declining as large wildfires broke out in mid-August, reaching a low of 68 GWh on August 22 before returning to approximately 100 GWh by the end of the month.

Solar-powered generation began declining again as wildfire activity rose in September, falling as low as 50 GWh on September 11 as PM2.5 smoke pollution increased.

The EIA report is available here.