The chances are you could get enough electricity to power your house. But to find out, you need Project Sunroof, Google's latest gizmo. At the moment it only seems to work in the US, but if you're there it will look at satellite data of your house, work out the area, angle and effect of any obstacles, then calculate how many panels you need to cover your consumption.
You can try it here:
http://www.google.com/get/sunroof
I tried with a couple of US address I did know:
1835 73rd Ave NE, Medina, Washington
and
1600 Pennsylvania Ave NW, Washington, DC, United States
But it apologised and said that Sunroof had not reached those addresses yet.
After failing to find data on the residences of Bill Gates and Barak Obama, I had more luck with 100 Waverley Oaks, Palo Alto, CA. Larry Page's address.
He has 1883 hours of sunlight per year, and 5,444 square feet available for solar panels. He could save 2,000 dollars by leasing panels.
You can fine tune the electricity bill, and chose between leasing, loaning or buying panels. If he bought panels, he could pay back the costs in around ten years, and save about 40 grand over the next twenty years.
