I'm making a lot of assumptions here, as I'm not an expert on solar panels (took a class that touched on them once, but I'm mostly just Googling here): * Typic

I'm making a lot of assumptions here, as I'm not an expert on solar panels (took a class that touched on them once, but I'm mostly just Googling here): * Typical efficiency of a consumer solar panel to day is about 12% * Average of 6 hours of sunlight a day over a year, sunlight providing 120 W/m^2 [1] * Rooftop of about 80 m^2 Total energy over a year comes out to about 2500 kWh.[2] Apparently the average household energy usage in the US is about 10000 kWh[3], which would imply that you could get about a quarter of your energy from solar. A few caveats: * Apparently some places get up to 2200 kWh/m^2 per year of sunlight[4], which would bring your solar panel total to about 21000 kWh a year. * Not entirely sure how big your average rooftop is. * Solar panels have been created with efficiency in the 40s of percent[5] Hopefully I'm not completely off with some of these, but it seems reasonable that a rooftop system can provide most or all of your power in the near future, depending on how sunny it is where you live. If it's not sunny, you might have a lot more problems, though. [1] According to https://en.wikipedia.org/wiki/Sunlight https://en.wikipedia.org/wiki/Sunlight, the World Meteorological Organization defines sunshine as a state of receiving at least 120 W/m^2 [2] http://www.wolframalpha.com/input/?i=365+days%2Fyear+*+6+hours%2Fday+*+120+W%2Fm%5E2+*+80+m%5E2+*+.12+*+one+year http://www.wolframalpha.com/input/?i=365+days%2Fyear+*+6+hou... [3] http://www.eia.gov/tools/faqs/faq.cfm?id=97&t=3 http://www.eia.gov/tools/faqs/faq.cfm?id=97&t=3 [4] http://www.nrel.gov/gis/images/map_pv_national_lo-res.jpg http://www.nrel.gov/gis/images/map_pv_national_lo-res.jpg [5] http://www.sciencedaily.com/releases/2013/09/130923204214.htm http://www.sciencedaily.com/releases/2013/09/130923204214.ht...