California’s Electric Vehicle Mandates Could Complicate Grid Reliability

California residents experienced the first intentional, rolling blackouts in the state in 19 years last week. Millions of families were left without power to cool their homes amidst a heatwave that covered much of the state and region, and as many as 3.3 million homes and businesses could face additional rolling blackouts as the state remains vulnerable to future spikes in electricity demand.

A surge in electricity demand, due largely to a spike in home cooling on top of typical demand levels, is partially to blame for the blackouts. Electricity demand often surges in the evening when some power generation sources begin to decline.

Overall electricity demand is only expected to increase in the years ahead. Electric vehicles need approximately 30 kilowatt-hours to travel 100 miles, which is the same amount of electricity required to power an average American home for a full day, including appliances, computers, lights, and heating or air conditioning. California’s zero-emission vehicle (ZEV) mandate and goal to hit 5 million ZEVs on California roads by 2030 could further strain California’s electricity reliability as millions of drivers plug in their cars each night.

The state also recently issued a regulation that would ban the sale of new diesel trucks by 2045. Charging long-haul delivery trucks that a diesel ban would encompass could further exacerbate the stresses on the grid. Those trucks will require much larger batteries than passenger vehicles, and charging those batteries will require even more electricity.

In total, California expects electric vehicles to consume 5.4% of all the state’s electricity by 2030, which is before the truck ban takes full effect. As EVs’ share of cars on the road increases, so too will the percentage of state electricity required to charge them.

California’s governor stressed the importance of grid reliability during a press conference last week. Grid flexibility and reliability are necessary to meet the surges in demand experienced in the Golden State and much of the western U.S. last week.  Additional electricity demand from ZEV mandates and diesel truck bans could increasingly make transportation less reliable.