Home electricity in California is about 45¢/kWh. If your F150 mileage is typical, you're getting about 2 miles per kWh. 600 miles would cost about $135 here in California. Meanwhile, a 20 mpg gas car would cost about $110/month at $3.65/gallon.
You must be paying about 4.7 cents per kWh, or about 90% less than you'd pay here.