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EV Home-Charging Solar Offset Calculator

Calculate how many kilowatts of extra solar capacity you need to cover your EV's home charging. Useful when sizing a rooftop solar addition for a new or existing electric vehicle.

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 (%)

Extra solar capacity for EV

2.77 kW

Few panelsSmall dedicated arrayMid-size additionLarge array

2-4 kW (about 5-10 panels) covers a typical commuter. The 2.77 kW example fully offsets 12,000 mi/yr; dropping to 50% offset would halve this to under 1.4 kW.

This is the added solar array size (kW DC) to offset your chosen share of EV charging; a typical residential panel is about 0.4 kW, so divide by ~0.4 to estimate panel count.

Solar Energy

Solar Savings Calculator

Calculate monthly bill savings from a solar PV system by multiplying solar production by your electricity rate. Use it to estimate the financial benefit of an installed or planned system month-by-month.

Monthly Solar Production (kWh)

Electricity Rate ($/kWh)

Fill in the required fields to see your result.

Key differences

	EV Home-Charging Solar Offset Calculator	Solar Savings Calculator
Category	Solar Energy	Solar Energy
Inputs required	6	2
Result	Extra solar capacity for EV (kW)	Monthly Savings ($)
What it does	Calculate how many kilowatts of extra solar capacity you need to cover your EV's home charging. Useful when sizing a rooftop solar addition for a new or existing electric vehicle.	Calculate monthly bill savings from a solar PV system by multiplying solar production by your electricity rate. Use it to estimate the financial benefit of an installed or planned system month-by-month.