I just read this over at Businessweek. Ray Kurweil:
Solar power actually is doubling every two years and has been for 20 years. Regardless of all the political debates, the actual output in watts has been doubling every two years. It’s eight doublings away from meeting 100 percent of our energy needs. So when I presented this to the Prime Minister of Israel, he said, “But do we have enough sunlight to do this with?” I said, “Actually, we have 10,000 times more than we need.” After we double eight more times and can meet all of our energy needs with solar, we’ll be using one part in 10,000 of the sunlight that falls on the earth.
Un. Be. Lievable.