Sales of electric cars are slowly picking up, but fans of vehicles like the Nissan Leaf and the Tesla Model S often wonder why the numbers aren't improving faster. A new study from Carnegie Mellon University provides an answer, and it has everything to do with parking.
The study was conducted by professors Chris Hendrickson and Jeremy Michalek and doctoral student Elizabeth Traut. Using data on the U.S. electrical infrastructure, the three discovered that less than half of drivers -- around 40 percent -- have consistent access to a parking spot at their homes that is situated near an electrical outlet suitable for charging.
While 40 percent may seem like a substantial number, it doesn't tell the whole story. For example, many of those drivers live in households with more than one vehicle, which would make charging more than one car overnight difficult, if not impossible.
The remaining 60 percent of U.S. motorists don't have reliable parking near a proper outlet. That's bad news for electric vehicle fans: given the slow state of charging these days -- which can require that owners wait up to eight hours for their electric cars' batteries to be fully charged -- having overnight access to a charging port is crucial for electric car adoption.
According to Michalek, the parking problem spells big trouble for electric vehicle manufacturers: "On the whole, less than half of U.S. vehicles have dedicated off-street parking at an owned residence in a location suitable for installing a charger... That means if we want more than half of the vehicles on the road to be electric, we're going to need major changes in residential parking — and that doesn't happen quickly."
The outlook gets more grim as the U.S. becomes increasingly urbanized and crowded. After all, it's one thing to add outlets to a suburban garage, but quite another to do so in a cramped condo building. As Traut explains, "Landlords have little incentive to invest in chargers that only some of their tenants may use, and homeowners simply don't have enough dedicated parking spaces to charge all of their vehicles."
Some analysts have suggested that public charging stations will soon become commonplace, as businesses begin earning extra bucks from EV owners who need parking spots with plug-in ports. But even if every Walgreens on the continent added a charging station, that wouldn't flip America to electric cars overnight. The problem of home chargers -- not to mention ho-hum EV battery capacity and range -- still need to be addressed, too.
Until those issues get resolved, electric cars will remain a small (though growing) segment of the U.S. auto mix.