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Everything You Need to Know About Charging an Electric Car

(Bloomberg) —

Most EV owners talk about a moment of zen — a point, typically a few weeks after buying their car, at which all the anxiety about charging and range just disappears. They’ve figured out the new technology and realized it wasn’t so hard after all. 

But for new owners, or the EV-curious, charging can be intimidating. How does it work? How long does it take? What is a kilowatt-hour, anyway? 

Fueling an electric vehicle involves chemicals and currents and cords, and it will never be as simple as pouring a slug of dead dinosaur goo into a tank. But it’s also not rocket science. On the spectrum of life tasks, the brainpower required to charge a car is closer to what you’ll need to use your microwave than, say, file your taxes. (And a kilowatt-hour is just the amount of juice needed to move an electric vehicle for about 3 miles, depending on the car’s weight and speed, the driving conditions, the weather, and a bunch of other little variables.) 

If you’re new to EVs and in the US, here’s a charging primer to get you up to speed. 

Where can I charge an electric car?

There are three options: a private charger (i.e. at your home or office), a public fast-charging site or a slower public charging site, known as a Level 2 station in EV-speak. The first option is typically the best and cheapest and doesn’t involve waiting. Another smart strategy is to top up at a Level 2 public station in a place where you would be spending some time anyway — say, the gym or the grocery store. These chargers typically add somewhere around 30 miles an hour (depending on both the charger and the car). They’re also relatively cheap to build and thus are popping up all over the place, particularly in shopping centers and in office parks. For every fast-charging station in the US, there are six slower, Level 2 charging sites. 

How do you charge an EV on a long trip?

You’ll probably want a so-called fast-charger to top up along the way. There are about 8,000 of these sites in the US, dotting service stations and rest stops along interstate highways and other major roadways. Once you punch in a destination, most EVs will now map the most efficient route, including stops for charging. 

Those who prefer the DIY approach can build their own itinerary via an app like Plugshare, a platform in which drivers crowdsource information on charging locations, including feedback on each site’s speed and reliability. You can filter results in myriad ways, weeding out slower chargers or networks you don’t prefer.

Can I take a road trip in an EV?

Good question. There are still vast electron deserts in the US thanks to the country’s sheer breadth, and its reluctance to subsidize charging infrastructure as aggressively as policymakers in Europe and China. You definitely want to think twice about an EV road trip in the Dakotas, for example, or the Deep South. 

That said, there aren’t many corridors left that are off the map for electric vehicles. And cords are getting more dense by the day, thanks to a recent federal infrastructure law that started sinking $5 billion into charging infrastructure this fall. Each state has its own plan to spend the money, but the goal from the Biden Administration is 500,000 new stations, including one every 50 miles on major throughways – even in the Dakotas. 

How long does it take to charge an electric car?

Most of the time, somewhere around 15 minutes will be enough at a fast charger. The latest electric vehicles and charging infrastructure are built to get the job done quickly. When the machinery on both sides of the cord is fairly current, a quarter hour will add more than 100 miles of range for the vast majority of contemporary EVs, which is typically plenty unless you’re on a long road trip. 

That said, the car can be a limiting factor. Many older or entry-level EVs don’t have the hardware to hoover up electrons quickly. Some only add two or three miles per minute, regardless of how fast a charger they are connected to. Environmental factors, such as cold weather, can hamstring the process too. 

You can check how quickly each EV model charges at Bloomberg Green’s Electric Car Ratings. Keep in mind, all EVs take on electrons more slowly the closer they get to “full.” This is called a charge curve and most EV veterans incorporate this dynamic into their refueling strategy.

How much does it cost to charge an electric car?

In the wild, probably somewhere around $18. That’s for a 15-minute session with an average contemporary EV at a typical rate (35 cents per kWh). In truth, though, this is probably the most complex question in charging. Prices vary widely by state and by network, and pricing structures differ too, with some companies charging by kilowatt hour and others by time. To complicate matters further, rates can vary based on the time of day and there are memberships, which provide lower per-unit prices in exchange for a monthly or annual fee. 

There are, however, loopholes. Some EV purchases these days come with free charging on certain networks for a certain period of time. And if you charge at work, odds are good it’s at least partially subsidized by your employer. Municipal charging stations often have gratis hours as well, say after 6 p.m. 

How much does it cost to charge an EV at home?

On average, about $50 a month. That’s based on how much Americans drive (13,476 miles per year, on average) and how much they pay for electricity (16 cents per kilowatt hour, on average). Though again, this varies widely based on where you live and how efficient your EV is at turning electrons into miles. For example, charging a relatively inefficient machine, say a GMC Hummer, in Hawaii, the most expensive state for electricity, could easily cost more than $300 a month — though Hawaiians generally drive less than the rest of us. 

How accurate are EV range estimates? 

That depends. Official EV range estimates reflect a mixed-route driving regimen as determined by the Environmental Protection Agency. Higher-speed cruising is only part of the equation; ditto stop-and-go traffic. Generally speaking, if you are going fast on an interstate, your observed range will be slightly lower than the estimate. In traffic or running errands around town, the opposite will be true — your battery will stretch farther than expected.

Keep in mind, your choices matter too. Cranking the AC, carrying heavy cargo and accelerating quickly, among other things, will hamstring distance.  

Can any car charge at a Tesla station?

Unfortunately, no. While the EV leader has opened some of its charging stations to other car brands in Europe, its US network is still only available to Tesla drivers. The company realized early that chargers sell cars and its ecosystem in America still has more fast-charging cords than all of the other networks combined. When it comes to EV market share, Tesla’s so-called Superchargers remain a sizable competitive advantage. 

Can you charge a Tesla at a non-Tesla station?

Yup, if you’ve got a Tesla, you can plug in at pretty much any public charging station, though you will need an adapter (Tesla uses a different plug type than the other EVs in the market, who have almost all converged on a standard format called J1772). Because of the sheer number of Teslas relative to other EVs, private, for-profit charging networks still desperately need your business. You get your charging cake and you get to eat it too!  

What happens if my EV runs out of battery? 

When range is getting low, most contemporary EVs do the math and automatically navigate to a nearby charger. Many also activate some form of “limp-home” function, a setting that shuts down climate control and other non-essentials in order to squeeze a  few more miles of distance. Even when the battery is all but dry, your car will drag itself along slowly — the accelerator pedal will feel mushy — to at least die in a safe place. At that point, there are emergency roadside charging services in some markets, but in many places, you’ll need a tow truck to move your bricked EV to a plug.

What’s the most efficient way to charge an EV?

If you want to prioritize battery life, charge mainly on slower networks, don’t fill up all the way and don’t drive until empty. Get a Level 2 charger at home (or work), plug in at 20%, top up to 80%. Rinse. Repeat. 

The government reckons most EV batteries will last between 12 and 15 years. And remember, the longer that you own your electric vehicle – and the further you drive – the more carbon it offsets. Get it up around 200,000 miles and it will start glowing green.*

*Metaphorically speaking.

To contact the author of this story:
Kyle Stock in Skillman at

© 2022 Bloomberg L.P.


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