As per a previous blog, I know that the 160 mile battery pack will need about 400kW Hours. This calculation will use the average solar insolation value and power would be supplied through a grid tie system. The 400kW hours was an inflated number to begin with. For a grid tie system, I will use 95% efficiency.
At my location, I have an average of 4.6 sun hours (Latitude -15). I need to make 400kW hours / 0.95 = 420 kW hours. I need to generate (420kW hours / 30 days =)14kW hours a day. What size array do I need? (14kW / 4.6 hours) I need a 3kW array. The generic installed cost is about $8 a watt for a grid tie system. A system would cost me $24,000 installed. Then take 30% off of that in the form of a Federal rebate. You get  $16,800. Not bad. The simple payback would be 47 Years. Maybe if you sized a system for the car and the house, the cost per watt would reduce to a more reasonable number. Say $6 per watt (I laugh to myself and say no way.) Then the cost would be $12,600. Even better! But just remember, this is at today’s energy rates. Who knows what they will be at in the future.