Companies typically put solar panels on their roofs to support clean energy and cut emissions, but a growing group of them are branching out to earn profits from selling solar energy. Apple and clothing company Patagonia are leading this trend that was initiated by Google which received a license to sell energy in 2010. The falling cost of solar and implementation of government incentives have made it attractive as an alternative—and cleaner—source of electricity to businesses. Walmart, Costco, Kohl’s, Ikea, General Motors, Johnson & Johnson, McGraw-Hill and Macy’s are also among the top solar customers as measured by the megawatts installed.