California, which is bracing for the year’s longest and most intense heat wave, faces the risk of its power grid being pushed beyond capacity, resulting in rolling blackouts for the first time since 2020.

Electricity consumption is expected to reach a five-year high early next week, with demand peaking at around 48,000 megawatts, according to regulators.
In order to avoid a shortfall, the state’s Democratic leadership has made a policy 180, supporting efforts to keep fossil-fueled plants operational and to extend the life of the state’s last nuclear power plant.

California’s grid has been strained by high heat and severe drought conditions, which increase power demand, primarily due to increased air conditioner use, and limit the state’s ability to produce hydroelectric power.

The grid is most stressed between 4 and 9 p.m., when demand remains high but solar power generation falls. To compensate for this imbalance, grid operators can ask residents to turn up their thermostats to at least 78 degrees Fahrenheit and avoid charging electric vehicles or using other large appliances during peak hours of demand through their Flex Alert program.

The state’s ability to generate hydropower has been reduced by 48% due to historic drought conditions and record-low reservoir levels. According to the US Energy Information Administration, in-state hydroelectric power accounted for only 7% of California’s utility-scale net generation last year, down from nearly 21% in 2017.
Energy is imported into California from five Western states: Arizona, New Mexico, Nevada, Oregon, and Washington. However, these states are also experiencing the same heat and drought as California and have shut down many of their own fossil-fuel-powered plants.

Since 2013, these states have retired more than 10 gigawatts of fossil-fuel-generating capacity, leaving them with few resources to sell to California.
Four of the five states that supply energy to California are also expected to be hit by the heat wave, limiting California’s ability to import power, according to operators.
California generates a large amount of renewable energy through wind and solar power, and it generates more solar power than it can use during the day. The challenge comes in the evening, when solar power drops but people continue to use air conditioners, emphasizing the importance of dispatchable generation assets.

The North American Electric Reliability Corporation rated the entire West as high risk for reserve shortages in its annual summer reliability assessment, with regulators warning that the state could face a power shortage of up to 1,700 megawatts on the hottest days.

Furthermore, operators warned of potential disruptions to the state’s solar photovoltaic, or PV, system, which converts solar energy into electricity. PV technology disruptions “continue to be a reliability concern,” according to NERC’s assessment, noting that California experienced four solar PV loss events between June and August 2021.

New wind and solar battery storage projects could keep that supply online for longer, though California has yet to match peak summer demand with its increased capacity. Many solar projects have also been stalled due to supply chain issues.
To mitigate supply risks in the short and long term, Western Electric Coordinating Council said in a 2021 assessment of resource adequacy that planning reserve margins “need to be increased — in some cases significantly — or other actions taken to reduce the probability that demand exceeds resource availability.”

California has been hailed as both a model and a cautionary tale for states attempting to phase out their own fossil-fuel-powered plants.

In recent years, California has backed away from nuclear power. The San Onofre Nuclear Generating Station, or SONGS, was shut down in 2012. According to a 2016 study published in the American Economic Journal: Applied Economics, the power generated by the Southern California facility was largely replaced by natural gas in the 12-month period following its closure, increasing emissions and driving up consumer costs by an estimated $350 million that year alone.

Researchers discovered that carbon emissions increased by 9 million metric tons in the year following the closure of SONGS, the equivalent of adding 2 million gas-guzzling cars to the road.