What if you could use your car’s battery to power your home? That’s the idea behind Nissan’s “Leaf to Home” technology. Nissan, in partnership with Nichicon Corporation, has built something called the “EV Power Station” (also featured in this month’s magazine). It takes power from the “Leaf to Home” device and funnels it into your home. It can also halve the amount of time you spend on an average Leaf battery charge, from eight hours to four.

But wait, what? Why would you want your car to charge your house? Isn’t it supposed to be the other way around–that you park your car and plug it in, so you can charge your battery and drive to work the next day?

The idea is clever, actually: it makes the car’s battery a node in your own personal mini-smart grid, sort of. And it could save you money. It’s all about giving customers “more power options,” the two companies said in a release (via Phys.org). Electricity prices vary by demand. Wouldn’t you like to store up energy during the low-cost periods, only to deploy it during the high-cost periods? If only you had… some sort of… giant battery you could use…

Enter “Leaf to Home” and the “EV Power Station” (and your Leaf, of course).

Or not your Leaf–yet. First, the thing is going on sale in Japan, priced at 480,000 yet (about $6,000). A government subsidy reduces the actual price by about a third, though, to roughly $4,100.

Does that sound like a good deal to you? I don’t know how high your electricity bill runs, but I know I couldn’t save anything on the order of four grand through a bit of clever energy arbitrage, not even over the course of several years. But I’m in a New York City apartment/closet. Perhaps there are households that could–but if you come from a household that blows through so much electricity as to make this economical, it’s somewhat puzzling why you bought a Leaf at all.

Survivalists, doomsday-predictors, and general sky-is-falling-ists might also take heart to know they could treat their car as an auxiliary generator in the event of an asteroid strike, zombie apocalypse, and the like. Though if the grid goes down all together, that’s only going to help you for so long.

So, would you buy the thing? More details on the device from the DigInfo video below.