Sales of electric vehicles are rising (thanks, high gas prices!), but EVs still account for only a small percentage of total vehicles on the road.

That could change significantly as progress is made in using the batteries of EVs to power homes or even sell electricity back into the grid.

This is known as “bidirectional charging” — systems that allow juice to flow into, and out of, electric vehicles.

A big step in this direction is in the works as Ford partners with PG&E, the Northern California utility, to test use of the Ford F-150 Lightning pickup truck as a power source.

In theory, a fully charged truck could power a home for up to 10 days.

PG&E says the tests will be limited and will focus on how an EV could serve as a back-up power source for homes during outages.

It will also look at challenges in funneling EV power back into the grid, similar to how solar systems work.

This is a potentially big deal, and other carmakers are exploring similar experiments with utilities. PG&E reportedly is working with General Motors as well.

It will take time, though. The technology for bidirectional charging is still in the early stages, and we’re a long way from making such systems accessible, and affordable, to EV owners.

But this is a great example of creating new energy efficiencies that can reduce dependence on fossil fuels and help combat climate change.

It’s also cool to think that your car or truck might not be just how you get around town. It can also be your own personal power plant.