How many amps do I need for a home EV charger?

A 32 amp charger on a 40 amp circuit suits many homes. It supplies 7.7 kW at 240 volts and adds 50 kWh in 6 hours 31 minutes. The Department of Energy says most home Level 2 chargers run at up to 30 amps, delivering 7.2 kW, on a dedicated 40 amp circuit.

EV charging counts as a continuous load under the National Electrical Code, so a charger can draw only 80% of its circuit's rating. A 40 amp circuit runs a 32 amp charger, a 50 amp circuit runs 40 amps and a 60 amp circuit runs 48 amps.

More amps help only if the car's onboard charger can take the power. The guide to home EV charger sizes lists the kW and charge time for each size. The Department of Energy recommends a certified electrical contractor for the installation.