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California asks people not to charge EVs during heatwave

Not a great look for the state that just vowed to phase out gas-powered cars in favor of battery-powered ones

One week after announcing plans to phase out autos powered by gasoline, California energy authorities are facing a heat wave so severe residents are being asked not to charge their electric vehicles during "flex alerts" designed to reduce stress on the grid.

According to a heat bulletin [PDF] issued by the California Independent System Operator (CAISO), temperatures across the state are expected to be 10 to 20 degrees warmer than typical between August 30 and September 6. Load on the electrical grid peaks between 4-9 pm, during which time CAISO said it may issue flex alerts urging Californians to reduce their electricity consumption. 

"The top three conservation actions are to set thermostats to 78 degrees [25˚C] or higher, avoid using large appliances and charging electric vehicles, and turn off unnecessary lights," CAISO said, noting that voluntary reduction in energy consumption could "prevent more drastic measures, including rotating power outages."

CAISO has already issued a flex alert for September 1 [PDF], and warned that additional alerts could be issued throughout the Labor Day weekend.

A poorly timed heatwave

A week ago, the California Air Resources Board (CARB) approved a package of regulations that called for the state to phase out the sale of new internal-combustion vehicles by 2035. With a record-breaking heat wave settling over it, California's decision to introduce additional power-hungry EVs to the state's grid looks a bit short-sighted, especially if climate change is likely to fuel similar weather patterns in the future. 

Mike Jacobs, senior energy analyst at the Union of Concerned Scientists, said that adding an EV to a home adds additional energy consumption equivalent to one or two air conditioners. Figures from the Department of Energy indicate that's the case for level-two charging, though level-one chargers that come standard with EVs draw less than half the power of an AC unit. 

It is too late to head off this electricity shortage in California, but electric vehicles aren't necessarily a death sentence for power grids, particularly if vehicle-to-grid (V2G) technology is more widely adopted in EVs. 

V2G technology would allow electric vehicles and stationary home battery systems built using EV tech to supply energy to the grid during peak demand periods, typically the same late afternoon to evening window California is gearing up to fight this weekend. 

According to a paper published by the Electric Power Research Institute (EPRI) assessing the capabilities of V2G: "The ability to discharge to the grid effectively doubles the kW capacity available for peak load reduction, and the discharge can be effectively timed to be coincident with peak loads." 

It's important to note that EPRI's data is based on projections of increased V2G-capable EV sales and grid operator adoption of such systems. Nonetheless, it indicates that such a technology could be a solution for future energy crunches, and could also act as an intermediary technology while power grids are overhauled to make way for variable energy generation provided by renewables. 

California's current lack of preparedness for this heat wave was made clear by Governor Gavin Newsom's state of emergency [PDF] declaration, in which he loosened several environmental restrictions to increase California's ability to generate enough electricity to beat the heat wave. 

Newsom said that California has significantly expanded its ability to generate and store renewable energy, but that supply chain disruptions and the climate crisis have interfered with gains and led to energy demands outpacing renewable supply.

According to the California government, 59 percent of California's energy generation in 2020 was from clean sources, with most of that coming from renewables, and the rest from hydroelectricity and nuclear power.

Earlier this year, California briefly generated 100 percent of its electricity from renewables, but a lack of battery capacity in the state means that much of that energy vanishes with the sun, leaving renewables unable to meet peak demand. 

To that end, Newsom temporarily suspended air quality regulations, water discharge restrictions, rules on not operating stationary or mobile generators, and other restrictions in his emergency declaration.

At the same time Newsom charged CARB, which passed the recent regulations to phase out gas-powered cars, with handling mitigation of "emissions from any operation pursuant to this Proclamation," a potential distraction from the board's electric agenda. ®

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