Solar EV Charging Calculator

Driving on Sunshine Calculator

Compare the fuel cost of a Gas Car vs. an EV powered by your own solar roof.

Avg EV gets 3-4 miles per kWh.
Levelized cost of solar is typically $0.05-$0.08 over 25 years. Grid power is ~$0.16+.

Annual Fuel Cost

Gas Car

$0
Per Year

Solar EV

$0
Per Year
Annual Savings: $0
Cost Per Mile: Gas $0.14 vs. Solar $0.02

How This Tool Works

The "Driving on Sunshine" simulator compares the annual fuel costs of a traditional internal combustion engine (ICE) vehicle against an Electric Vehicle powered by 100% home-generated solar energy. It calculates the Cost Per Mile for both, exposing the massive delta between fossil fuels and renewable electricity.

By using the Levelized Cost of Energy (LCOE)—the total price of your solar system divided by its 25-year output—we can accurately value the electricity you 'give' to your car, rather than just assuming it's free.

How to Use the Simulator

  • Daily Commute: Enter your round-trip mileage. The average US driver covers 11,000–14,000 miles per year.
  • Gas Price: Enter the current local price for regular unleaded.
  • Gas Car Efficiency: Enter your current vehicle's MPG.
  • EV Efficiency: Enter the mi/kWh rating of your target EV (Tesla Model 3 is ~4.0, larger SUVs are ~2.8).
  • Solar Cost per kWh: Default is $0.06. This is the effective cost of 'owning' your power rather than 'renting' it from the grid.

Fuel Cost Comparison

For a 30-mile daily commute (10,950 miles/year):

  • Gas Car (25 MPG @ $3.50/gal): ~$1,533 per year
  • Solar EV (3.5 mi/kWh @ $0.06/kWh): ~$187 per year
  • Annual Savings: ~$1,346
  • Verdict: Over 10 years, driving on sunshine saves you over $13,000 in fuel alone, nearly paying for the solar system itself.

Why Solar Charging is the Ultimate ROI

Solar energy is a fixed-cost asset. Once installed, your 'price per gallon equivalent' is locked for decades:

  • Inflation Protection: While gas prices fluctuate based on global geopolitics, your roof's power output never changes price.
  • Grid Independence: Even if utility rates double (as they have in many states recently), your car remains cheap to drive.
  • Full Cycle Sustainability: Charging an EV with solar is the only way to achieve true zero-emission transportation.

Frequently Asked Questions

Is it cheaper to charge an EV with solar than with the grid?

Yes, significantly. While grid electricity costs between $0.15 and $0.30 per kWh depending on your location, the 'Levelized Cost of Energy' (LCOE) for home solar is typically $0.05 to $0.08 per kWh. This makes solar charging 2-4x cheaper.

How many solar panels does it take to charge an EV?

For the average American commute of 30 miles per day, you need roughly 8-10 kWh of energy. A 2kW to 3kW solar array (about 6-8 panels) is usually enough to cover a full year of driving.

What is 'Driving on Sunshine'?

'Driving on Sunshine' is a term used by EV owners who power their vehicles exclusively with home-generated solar power, effectively decoupling their transportation costs from both oil markets and utility grid fluctuations.
Expert Tip: Consider a 'Smart EV Charger' that can communicate with your solar inverter to charge the car only when the sun is shining, minimizing grid draw even further.