Q: Does it make sense to use solar panels to charge an electric vehicle.
A: When my Tesla is charged from my solar panels (which generate electricity at 7c per kWh) I can drive for 2c per mile. A gasoline-powered car getting 30 mpg on gas at $3 a gallon costs 10c per mile. Did I mention the zero carbon footprint of driving my Tesla on solar power?
We have solar but can’t produce enough (too many trees around the house) to also cover our electric car.
Is there a good way to find out how many solar panels it costs to pay for let’s say 10,000 mi/year? Thanks.
Hi Marion, An electric vehicle gets about 3 miles per kilowatt-hour of electricity. So driving 10,000 miles per year will use about 3,300 kWh of electricity. A typical solar panel in MA will generate about 1kWh per year for every 1W of rated power. So you would need a solar array rated at 3.3kW to generate 3,300 kWh per year. Typical panels today get generate about 330W each so you would need about 10 panels to drive your car for a year on zero carbon electricity. A 3.3kW array would cost you about $10,000 today before the federal and state subsidies and about $3,000 after these subsidies. I can drive my Tesla at 2c per mile when charged from my solar panels. My old BMW cost 10c per mile ($3 per gallon of gas at 30 mpg). It is 80% cheaper to run an EV than an gas-powered car.