Heron’s Nest [is] North Carolina’s first residential “microgrid” development. A microgrid is a network of buildings that essentially acts as a miniature power grid. It can operate outside of the larger municipal electrical system by ensuring backup power for the entire development, which can be produced by a solar array system and stored in a battery. “The rooftop solar and the sense of security we got knowing that you’d have power during a storm sealed the deal for us,” said Mr. Moulder, 57, a semiretired inventory manager. Heron’s Nest is part of wider electric cooperative in North Carolina, a membership-based utility that allows customers, acting as shareholders, to benefit from revenue that is either diverted back into the utility or passed along as dividends. “This is why microgrids are very attractive to us, because when we lower the costs of maintaining the grid, the profit goes back to the customer as a lower utility bill,” said Nicky Nance, a key accounts and renewable specialist with Brunswick Electric. The 31 homes at Heron’s Nest have sold quickly. It was easy to explain to buyers how rooftop solar panels, included in the price of each home, could lower a utility bill, and how the microgrid would generate power when residents most needed it. While residents can feel secure knowing they are generating and storing power, a microgrid also eases the burden on the local utility, because it can disconnect from the larger grid during a period of overload.