Solar + EV Charging Calculator

We compare the annual cost of charging an EV against the annual cost of fueling a comparable gas car.

EV cost = (annual miles ÷ EV efficiency in miles/kWh) × your electricity rate. We use your local rate by default; you can change to a lower rate if charging primarily from solar production (effectively your levelized cost of solar electricity).

Gas cost = (annual miles ÷ MPG) × gas price per gallon.

The difference is your annual fuel savings. Over 25 years (typical solar warranty period), this compounds into substantial lifetime savings — and your driving carbon footprint drops to near zero when paired with a properly sized solar system.

Pairing solar with an EV is one of the highest-leverage moves in residential energy. Gasoline at $3.50/gallon costs roughly 12 cents per mile in a 28 MPG car. Solar electricity at a levelized cost of 5 cents/kWh costs roughly 1.4 cents per mile in an efficient EV.

That 10-cent-per-mile gap adds up fast. At 12,000 miles per year, you're saving $1,200 annually. Over a 25-year solar warranty, that's $30,000+ in fuel savings — on top of the electricity offset savings on your house.

The sizing implication: an EV adds about 3,000–4,000 kWh of annual electricity demand to your home. If you're sizing solar for both house and EV, plan for 11–14 kW instead of the typical 8 kW residential install. The incremental solar capacity is far cheaper than buying that electricity from the grid forever, and the federal tax credit applies to the full system cost.