Modern cels don't really need direct sunlight anymore and can make do with dispersed light; it is just that the total yield is lower. I calculated 50 Watts per sq mtr. where modern cels are rated up to 150 watts in good lighting conditions. Additionally, I wrote the post with the Yanks in mind and they are alot closer to the equator then either one of us !

In our situation a combi power station with a solar cel and a small wind turbine is probably best.

Something like a (smaller version) of the darrieux turbine depicted here

http://www.quietrevolution.co.uk

The version depicted is quite large at 5 mtr tall and 3 mtr width but it also does between 4000 kWh and 10.000 kWh per year. Actually, almost twice to 4 times the amount my household uses annually including everything.

The depicted vehicle would only need in the order of 150 kWh per year if it does 12.500 km/7800 miles (= equal to 20L or 6 gallons of gasoline a YEAR when converted at 50% efficiency = typical powerstation). So for 400 kWh (= need + ample margin) our home turbine would be 1.5 mtr tall and just under a mtr wide. Fitted to the chimney of our houses. Actually, you can home build a darrieux turbine yourself. The underlaying principle is not that hard.

Wouter