Electric Cars and the Power Grid: Is the U.S. Ready?
Electric vehicles are becoming a normal part of American life. Is our infrastructure ready?
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After more than a decade of hype, electric vehicles are finally gaining sales traction in the United States. According to analysis from IHS Markit, EVs accounted for 2.8% of new vehicle registrations in December 2020—more than triple EVs' share of retail sales three years ago. But that doesn’t mean that all the problems of EV adoption have been solved.
As more Americans choose and use EVs, the effect of electric vehicles on the power grid will grow. For the most part, electricity providers think that small behavioral tweaks by EV owners can keep the stress on the grid manageable. But building charging infrastructure in remote areas and planning for natural disasters will pose a bigger challenge.
What is the electrical grid?
If you’ve never been quite sure what the electrical grid is, aside from a vague awareness that one can go off it, allow us to explain briefly: The electricity that’s allowing you to read this article originates at a generator where electricity is, yes, generated in one of a variety of ways. Your power might come from a coal-fired power plant, a solar panel, or a wind turbine. One way or another, the power created at the generator is routed to high-voltage wires that can carry it long distances to your neighborhood, where a transformer lowers the voltage before delivering the electricity to your home, and finally to the wall outlet, where you can get shocked if you have faulty wiring..
The U.S. Department of Energy says that 70 percent of the country’s transmission lines (the wires that carry the electricity from a power plant to your home) are more than 25 years old and the average power plant is 30 years old. It also acknowledges that parts of the grid are under strain.
But EVs probably won’t be the final straw for the grid. As more people buy EVs, utility providers plan to manage an increase in demand for power by incentivizing customers to charge their EVs at night, when demand for electricity is lower, by offering lower pricing.
Where could we use more infrastructure?
Public charging presents a tougher problem for electric cars and the power grid. The DC fast-charging stations that put the dream of EV road trips in reach are power-hungry and are used at all hours of the day. An EV plugged in there draws as much power as 50 homes during its short charging period, according to a report from the Pacific Northwest National Laboratory (PNNL).
Charging stations located in city centers are probably up to the task. But providers looking to grow a nationwide charging service will inevitably have to build stations in remote areas where the existing grid wasn’t designed for a steady stream of cars sucking down electrons. Electrify America has installed battery power storage at 100 of its stations and solar panels at 30 rural stations to ensure that even far-flung ports can provide a steady flow of energy. Tesla says its next-generation Superchargers will also feature solar panels and battery storage.
Bad weather presents a challenge
Still, the grid will inevitably fail sometimes, to the detriment of EV owners. The winter storms that struck Texas in early 2021 provide one extraordinary example. Anyone looking to charge an EV during that crisis would have been out of luck. And rolling blackouts are now relatively common in California, where EV adoption is highest.
Some EVs seek to address the blackout problem with the ability to power a home or work site from the vehicle’s battery. There were anecdotal accounts of Ford F-150 PowerBoost Hybrid owners using their vehicles’ onboard generators this way during the Texas power outage.
Those benefits won’t be of much help to drivers who prefer to use their EVs to flee to safer ground. One study from researchers at Princeton and Arizona State University modeled a hurricane evacuation in Florida in a scenario where most vehicles on the roads were EVs and found that the demand effect of electric vehicles on the power grid could cause “cascading failure” of the power network. The study recommended better central planning for charging networks and the adoption of gas-electric hybrids alongside EVs to minimize the demand for scarce charging resources. Of course, we’re a long way from a mostly EV fleet in Florida, but even gasoline cars are vulnerable to supply shortages during evacuations, too.
The PNNL reckons that the country’s existing electrical infrastructure could support up to 24 million EVs. A count from the Department of Energy found only around 1 million EVs registered in the U.S. in mid-2021, leaving plenty of breathing room. If anything comes of the ambitious pledges some automakers have recently made to begin to phase out gasoline-powered cars by 2040, there will eventually be tens of millions more EVs on the road than our current infrastructure could support. But until then, there’s time—and, with the passage of the U.S. federal government’s Bipartisan Infrastructure Deal, tens of billions of dollars—to build a grid that’s ready for the revolution.
