Electric vehicles still make up just a tiny slice of the vehicles on the road across the United States.
Still, with impending regulations and more longer-range electric vehicles soon to arrive, governments far and wide recognize the need to encourage the installation and growth of public charging stations.
Just how many charging stations is enough to support the current and future crop of plug-in electric cars?
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According to a recent report by AutoExpress that considers that question for the U.K., less than one charging station was installed for every six electric vehicles sold there in 2017.
Including the British version of low-speed electric vehicles (known as quadricycles), electric motorcycles, and plug-in commercial delivery vans, there are 8.9 plug-in vehicles for every public charging point, Autocar calculated.
That's "close to the European Union’s preferred maximum ratio of 10 per public charging point," it said.
2018 Kia Niro Plug-In Hybrid charging at Crevier BMW, Santa Ana, California, Dec 2017
Meanwhile, the far larger and more geographically diverse United States isn't even close.
Data from the U.S. Department of Energy's Alternative Fuels Data Center indicates more than 16 electric vehicles are on U.S. roads for every public charging outlet.
Furthermore, of the 47,110 charging outlets in the United States, 14,223 of them—30 percent—are in California, the state with the largest electric-vehicle market in the country.
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If California has roughly half the 800,000 or so plug-in vehicles in the country, the commonly used figure, that's more than 25 vehicles per charging outlet.
Earlier this month, Pacific Gas and Electric (PG&E) announced it would support the roll out of 7,500 charging stations in California between now and 2020.
Still, considering the alarm raised in the United Kingdom at being close to the theoretical 10 vehicles per public charging outlet limit, the United States is considerably behind.
Tesla Model S at Supercharger site in Ventura, CA, with just one slot open [photo: David Noland]
That should be offset to some extent by installation of charging stations in private garages, car ports, and driveways, since more U.S. residents have off-street parking adjacent to single-family homes than in the U.K.
To tackle the more specific issue of DC fast charging along highways, a number of state-level initiatives are aimed at boosting public charging stations along high-traffic corridors.
A partnership comprised of eight western states—Colorado, Nevada, Utah, Idaho, Montana, New Mexico, Wyoming, and Arizona—plans a significant boost in high-speed charging along those states' interstate highways to support electric-vehicle sales there.