Michio Kaku: Some people think that the time is right for the solar revolution, that one day solar power will replace oil and we'll all live in a world that is clean and renewable. Well, not so fast. I believe in solar power. However, there are problems that we have to face, and one of them is low efficiency. The other one is lack of a storage facility like a battery. That's' the weak link. We simply don't have the efficiency of solar cells necessary to make it economical and competitive today, and the ability to store the energy for long periods of time when the sun is dark, when there are clouds and your solar panels don't work. So my point of view is this: I think in the coming decade, as oil prices start to rise and as the cost of wind and solar and renewables start to drop, the two currents will probably cross in maybe ten years. So in ten years it will be the marketplace which then begins to drive the whole thing forward because of the dropping cost of solar cells and ! rising efficiency and the rising price of oil. Now, why do I believe that oil prices will rise? Because of something called Hubbert's Peak. Hubbert was a Shell Oil engineer way back in the 1960s who predicted that we would hit the halfway point for the production of oil in the United States and after that the bell-shaped curve would curve the other way and we would become an importer of oil. Well, people laughed at him because they said that, "Well, wait a minute. We have Alaska. We have Texas. We have
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