Duke Energy outlines solar grid ambitions

US energy giant reveals plans to expand smart grid project to deploy solar panels on customers' buildings capable of feeding power back into the grid

US power giant Duke Energy is planning to ask permission for a network of residential solar panels, installed on customers' roofs. The project, which could cost $100m, would see homes sending locally-produced electricity back to the grid.

The North Carolina-based firm is releasing few details of the project, which is still in development, but spokesman Dave Scanzoni said that the initiative complements a wider, ongoing project to digitise the electricity grid.

Duke Energy has been installing smart meters in homes that make it possible to manage electricity demand more accurately. The company will have finished installing the technology in 5,000 homes by the end of the summer, and hopes to have all four million customers fitted with smart meters in five years.

"One option could be that we own and install the panels, and customers get a discounted rate on their electricity," said Scanzoni. Batteries would store the electricity so that houses could use it, or so that the utility could channel it back to the grid to meet demand, he added.

Currently, the utility gets 71 per cent of its energy from coal, 26 per cent from nuclear, and three per cent from other sources, including hydro, natural gas, oil and wind. But despite this reliance on coal the firm has set itself a goal getting out of fossil fuels generation by 2050.

The company is also seeking to position itself as a champion of the cleantech sector with president and chief executive Jim Rogers recently criticising the US for falling behind in renewable energy research, and proposing a three-tenths of a cent energy tax on each kilowatt hour of energy produced. Such a move would raise $11bn annually for cleantech R&D in the US, he said.

Rogers currently has a prototype of the solar system running at his own house. The solar installation cost $24,000, while the battery to store the electricity cost $10,000.

The company said it will file an application to proceed with the project with the North Carolina Public Utilities Commission by the end of this year.