Solar + EV planning

How Much Solar Do You Need to Charge an EV?

Turn annual miles and vehicle efficiency into annual charging energy, then estimate the extra solar capacity and panel count needed to offset it.

State

Miles driven per year

mi/yr

Vehicle energy use

Wh/mi

Charging-loss allowance

Panel power

EV charging energy from wall4,000 kWh/yr

Average monthly charging333 kWh

Additional solar capacity2.7 kW

Approx. additional panels7

This uses the selected state's planning solar yield, not ZIP-specific PVWatts. Enter your vehicle's EPA or measured Wh/mile when available. Winter weather, highway speed, towing, cabin heating and charging losses can materially change real energy use.

Why EV charging changes solar sizing

An EV can add thousands of kWh to annual household electricity use. If a solar proposal was sized from old utility bills that predate the vehicle, the resulting array may be too small for the home's new load. Use measured vehicle efficiency and expected annual mileage whenever possible.