The astounding growth in wind and solar power coupled with their plummeting prices means that we are now radically rethinking how we produce, transmit, and sell power. Customers want 100 percent renewable energy, states want to cut their greenhouse gas emissions, and utilities are scrambling to come up with new business models and infrastructure to accommodate them.
The wind and the sun are some of the most abundant sources of energy in the world, and they’re free. But the big challenge of harnessing them is the simple fact of their intermittent availability: In general, the sun shines during the day, which means the amount of solar energy available is highest during the day. Wind, meanwhile, is usually strongest at night, so wind energy peaks after sunset.