SanDiegoDave100 writing in The Motley Fool ran some numbers on using Solar PV to provide 100% of his homes electricity and electricity to a Tesla electric car.
His current cost for 600 kWh per month costs $101 and gas for his car $180 for a total of $281.
At $0.25 kWh/mile and 1500 miles per month he would require 375 kWh of electricity, combined with 600 kWh for the house would require 975 kWh of solar power. He determined that he would require an 8 kW solar system, for a San Diego location, at an installed cost of $55,000 before rebates of $17,600 for a net of $37,820.
A home equity loan of $37,800 at the current 6.5% rate would be only $239/month, a saving of $40/month.
He neglected to state how he would store the electricity so he could operate his house and charge his car at night, but it still is an interesting calculation. Perhaps he could be tied to the grid and sell his surplus during the day and buy electricity at night, but he did not make that calculation. The rates might even be in his favor if he was selling at peak rates and buying at off peak rates.
Thanks to AutoblogGreen for the tip.