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EV Home-Charging Solar Offset Calculator

Find how much extra solar you need to cover your EV's home charging, from annual miles, vehicle efficiency, charging losses, sun hours, system losses, and your offset target.

Annual miles driven (mi/yr)

Vehicle energy use (kWh/100mi)

Home charging losses (%)

Peak sun hours (daily average) (h/day)

Solar system losses (%)

Share of charging to offset with solar (%)

Solar Energy

Solar Panel System Sizing Calculator

Size a rooftop solar PV system from your real electricity usage, local peak sun hours, system losses, and your target offset — and get the number of panels you actually need.

Average monthly electricity use (kWh)

Peak sun hours (daily average) (h/day)

Share of usage to offset (%)

System losses (inverter, wiring, soiling, heat) (%)

Panel power rating (W)

Key differences

	EV Home-Charging Solar Offset Calculator	Solar Panel System Sizing Calculator
Category	Solar Energy	Solar Energy
Inputs required	6	5
Result	Extra solar capacity for EV (kW)	Solar panels needed (panels)
What it does	Find how much extra solar you need to cover your EV's home charging, from annual miles, vehicle efficiency, charging losses, sun hours, system losses, and your offset target.	Size a rooftop solar PV system from your real electricity usage, local peak sun hours, system losses, and your target offset — and get the number of panels you actually need.