A recent article in The Economist argues that a new standard for USB plugs, out next year, could help promote a shift to using DC power in offices and homes, which could reduce energy consumption and make solar power more attractive.

A lot of the things that use power in a home or business–computers, laptops, smartphones, LED lights, many motors—run on DC power. And converting the AC power at an outlet to DC wastes a considerable amount of energy. If you have solar panels, you add another layer of waste. Solar panels produce DC power, which is converted, at a loss, to AC power, only to be converted back to DC when you charge your phone.  

It’s already possible to set up DC grids that skip AC and directly power DC devices with DC solar power. Such grids are used in data centers for example. But a consumer-friendly USB standard might make the switch easier.