New York Times, Mar. 13, 2017, by Diane Cardwell.
https://www.nytimes.com/2017/03/13/business/energy-environment/brooklyn-solar-grid-energy-trading.html?_r=0

"In a promising experiment in an affluent swath of [Brooklyn], dozens of solar-panel arrays spread across rowhouse rooftops are wired into a growing network. Called the Brooklyn Microgrid, the project is signing up residents and businesses to a virtual trading platform that will allow solar-energy producers to sell excess-electricity credits from their systems to buyers in the group, who may live as close as next door."