T.R. Reid writes from Arizona:

“Some states have oil. Some have coal. Here in Arizona, we’ve got sun,” said Hansen, a vice president of Tucson Electric Power Co., as he squinted through heavy-duty sunglasses. “And now we’re using that resource to reduce our dependence on fossil fuels.”
On an utterly shadeless expanse of high desert plateau near the New Mexico border, Hansen manages America’s largest solar-powered electric generating station. It looks at first glance like a long, long row of windowpanes propped up to face the sun. In fact, each “window” is an array of photovoltaic cells that generate electric current when exposed to the light.