Matt Slocum / AP
Prices for solar energy are dropping and will keep dropping, Kammen and Pernick say. For Kammen, the trend means that solar will finally start grabbing significant market share away from energy sources such as coal and oil — and catch up to the deployment of wind power, which itself is forecast to become as big as nuclear.
Lump all three sources of energy together, and "we are now starting to talk about more than half of our energy coming from clean carbon sources," he says, noting the caveat that nuclear has its own concerns, such as waste storage that lead to questions about its overall cleanliness.
According to Pernick, the price drops in solar — as much as 50 percent from 2008 highs — will lead to cost parity with other energy-generating technologies. "That is the big Holy Grail … and we are going to get there," he says.
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