Flagstaff, AZ – In Arizona, the green power movement is being driven largely by a state mandate requiring all private utilities to produce at least 15 percent of their electricity from renewable sources by 2025. And 30 percent of that has to come from so-called "distributed" sources, like rooftops. So utilities, with help from the state and federal government, are offering big incentives to homes and businesses that "go solar." And that's helped make it more affordable than ever. Arizona Public Radio's Gillian Ferris Kohl reports.