Charging an electric car at home
Most electric car owners do the bulk of their charging at home, usually overnight. That is the main reason an electric car can cost less to run. This guide covers the two kinds of home charging, how to estimate what it costs and what to check first.
Level 1 and Level 2
According to the U.S. Department of Energy's Alternative Fuels Data Center, most drivers of electric vehicles, including plug-in hybrids, charge overnight at home with AC Level 1 or AC Level 2 equipment (source).
- Level 1 uses the cordset that comes with the vehicle and a standard outlet. The DOE notes many owners meet their daily driving needs by charging overnight this way, with no extra equipment or installation, provided there is an outlet on a dedicated branch circuit near where they park.
- Level 2 uses 240 V equipment. It suits drivers with longer commutes, irregular schedules or larger batteries that need more than one night to fill. Many Level 2 units are "smart" and let you set charging timers.
A qualified electrician can tell you whether your home has enough electrical capacity for Level 2 and add circuits if it does not. The DOE recommends safety-certified equipment, and state or utility incentives may help offset the cost of charging equipment.
Estimating the electricity cost
The DOE's method is simple. The efficiency of an EV is given in kWh per 100 miles, so cost per mile is the price per kWh multiplied by the kWh used per 100 miles, divided by 100. With the Tesla Model 3 Standard RWD's EPA rating of 24.3 kWh per 100 miles and the U.S. average price of 18.31 cents per kWh, that is about 4.4 cents per mile, or roughly $534 over 12,000 miles. Use your own rate from your utility bill for a better number.
Check your rate plan
- Some utilities offer time-of-use or special EV plans with cheaper overnight electricity. If you can charge off-peak, you may pay less than the average price we use. Ask your utility.
- Some plans have tiers, where usage above a threshold costs more. Adding a car can push you into a higher tier.
- Your bill also has fixed charges and taxes that do not change with how much you charge. Our tool uses the per-kWh energy rate.
If you cannot charge at home
Apartment dwellers and street parkers often rely on workplace or public charging. Public fast charging usually costs more per kWh than home electricity, so run the comparison with a higher electricity price. If the savings disappear at that price, a hybrid may fit better.
Questions to ask before you buy
- Where will I park, and is there an outlet or room for a charger?
- How many miles do I drive on a typical day?
- What does my utility charge, and is there an EV or time-of-use plan?
- Are there utility, state or provincial incentives for chargers or installation?