Electric Vehicle Solar Sizing Directory

When sizing a residential photovoltaic (PV) solar system for electric vehicle charging, the vehicle's EPA efficiency rating (measured in miles per kilowatt-hour, or mi/kWh) is the fundamental governing factor. An ultra-aerodynamic sedan like the Tesla Model 3 Highland achieves about 4.1 mi/kWh, requiring only 8.5 kWh to travel 35 daily miles.

In contrast, a heavy electric pickup truck like the Ford F-150 Lightning or Rivian R1T yields approximately 2.0 to 2.3 mi/kWh, requiring about double the electricity (about 17 kWh) for the same commute. Consequently, with average US sunshine, truck owners need about 10 to 11 panels of 400 W, compared with about 6 to 7 for an efficient sedan.

Charging losses matter too. Home Level 2 charging is usually about 85% to 95% efficient, so some electricity is lost as heat in the car's onboard charger and battery. The EPA measures each car's energy use at the wall outlet, so its rating already includes these losses, and we don't add them a second time.

On top of that, our directory allows 18% for losses on the solar side (inverter, wiring, heat and dust), so the panel counts are slightly cautious. Shade, roof direction and winter weather can still change your real result.