What is the difference between Level 1 and Level 2 charging?

Level 1 uses a standard 120 volt outlet and adds about 5 miles of range per hour. Level 2 uses 240 volts at home or 208 volts at commercial sites and adds about 25 miles per hour. For a 50 kWh charge, that is about 34.7 hours on a 12 amp outlet versus 6 hours 31 minutes at 32 amps.

Those range figures come from the Department of Energy's Alternative Fuels Data Center, which assumes 1.9 kW for Level 1. Level 2 equipment ranges from 2.9 kW to 19.2 kW. Both use the same J1772 connector, and every EV sold in the US can use both.

Level 1 needs no installation. Level 2 charging needs a dedicated 240 volt circuit, usually 40 amps for a 30 or 32 amp charger. The guide to EV charging levels adds DC fast charging to the comparison.