NREL has a new web app that allows you to roughly layout a solar PV system on the roof of your house. just enter your address.
the dude who lives in the house in the pic could fit a 14 KW system on his roof in the little blue square i have drawn just north of the rose garden. the system would pay for itself in 5.8 yrs if his current cost of electricity were 9 cents/kWh.
note the name of the app - InMyBackYard -that’s how i feel about solar.