Charging At Home Makes EVs Cheaper To Own

Car and Driver has had a Tesla Model 3 in its long range test fleet for over a year, during which time the car has racked up 24,000 miles of driving. So it’s fair to say the magazine has some long term experience with the Model 3 and has learned a thing or two about driving an electric car along the way.

Courtesy of Tesla

The first lesson is that the car is constantly changing as its operating software is regularly improved via over the air updates. The second lesson is that charging at home is far less expensive than paying to charge at Tesla’s Supercharger locations. CD says, “Assuming the national residential average electricity cost of 13.6 cents per kilowatt-hour and our car’s actual 84 MPGe efficiency, our Model 3 has cost us 5.5 cents per mile during its first 24,000 miles, or just over $1300 total. If we charged solely at Superchargers, however, which, at 26 cents/kWh costs the equivalent of $8.76 per gallon, that average cost jumps to 10.4 cents per mile and totals to just over $2500. That nearly matches our 10.7-cent average in our long-term BMW M340i test car, which is powered by a 382-hp turbocharged inline-six and has averaged 26 mpg during our test.”

The long term test vehicle got plenty of use — 24,000 miles in about 14 months is well above average miles. Because many of the Car and Driver staff do not have wall chargers at home, about a third of all the charging was done at Tesla Supercharger locations. In the end, when all the numbers were crunched, the average cost of “fuel” for the Model 3 came out to about 7 cents per mile. That number, of course, depends entirely on what you pay for electricity where you live. In some parts of the US, off peak rates can be as low as 5 cents per kWh. In other locations, like Hawaii, where electricity costs $0.32 per kWh, the cost of charging would be nearly triple what Car and Driver paid. Of course, the price of gasoline in Hawaii is higher as well, about $3.25 a gallon.

By way of comparison, the average cost for a base level Electrify America member is $0.43 per kWh, not quite double what Tesla charges its customers. Blink charges between $0.39 and $0.79 per kWh while ChargePoint says the owners of its chargers set their own prices, which makes it a little hard to figure out in advance how much using its network will cost at any particular location, although many ChargePoint chargers are free.

The Take Away

Car and Driver puts its finger squarely on the most significant barrier to EV ownership — access to charging at home. With it, your a cost of operation will be far lower than with a conventional car powered by an infernal combustion engine. Without it, you may not see any savings at all, other than from reduced maintenance expenses.

There is a lot of chatter about expanding public charging networks as a way to increase the speed of the EV revolution but not a lot of talk about installing wall boxes at homes and work locations. Many of those wall boxes are connected to the internet, which allows them to charge during the wee hours of the morning when rates are lowest. In the future, they may also allow EV drivers to share the electricity in their car’s battery with the grid, which will actually put some money back in their wallets.

Volkswagen is offering smart chargers to its customers in Germany while other companies like Hyundai are partnering with local electricians to make getting a home charger installed simple. California now requires all new homes to have built in charging capability. Putting in the wiring needed to power a wall charger is simple and cheap during the construction phase. The cost goes up significantly once a home is completed. Tesla also works closely with its customers to make getting a home charger installed a simple and convenient process.

Perhaps people who are skeptical about EVs are a little put off at first about having to pay more to get a home charger installed but that cost will be offset many times over as the miles pile up. Home charging is perhaps the least understood part of the EV experience. In effect, an EV driver starts every day with at least an 80% SOC in the battery. Most will rarely visit a public charger except those few times each year when it is necessary to go over the river and through the woods to Grandmother’s house.

If you are considering the purchase of an EV, ask the dealer about getting a home charger installed. If all you get is a shrug and a blank stare, walk out and patronize a dealer who “gets it.” If they don’t know enough to advise you about home charging options, they don’t deserve your business.