Residential solar is surging in the U.S. The price of the average solar panel is down more than 60 percent in the past five years, and more and more solar customers are earning credit for the extra energy they produce for the grid. But that practice – known as “net metering” – has some utilities worried about the future. In a number of states, utilities are fighting to cut back on net metering, as concerns grow about the cost of maintaining the grid and adapting to the changing energy picture. For this month’s Environmental Outlook, we look at what the surge in solar could mean for consumers…and for the future of the electric grid.