All known fossil fuel reserves could be totally spent within the next 100 years, according to recent estimates. The most common form of solar power is the use of photo-voltaic (PV) cells to convert solar energy into electricity. You will probably recognize them from calculators and road signs. Covering an area of 366,375km^2 with PV cells could provide enough energy for our yearly demands. That's roughly the size of Germany, or 0.2% of the Earth's total land surface.
Infographic by: quickquid
Infographic by: quickquid