The US Energy Department is investing $3.9bn in ‘smart grid’ technology, aimed at making power transmission around the country more flexible.

Addressing utility executives at an industry meeting US Energy Secretary Steven Chu said the funds would help create a system to allocate electricity more efficiently.

This will done through improved power lines or by allowing batteries in hybrid cars to feed back into the grid when needed.

“Right now, the way we distribute energy, it’s like plumbing – it’s down the hill,” he told Reuters reporters at a news conference after his speech at the Edison Electric Institute conference in San Francisco.

When asked about people objecting to high-voltage power lines being built near their homes as part of a smart grid, Chu said he would appeal to US national interests.