From the people that brought you private space travel comes another ambitious techno challenge — a hyper-green battery that can store electrical energy in vast quantities, with super-quick recharging abilities and without environmentally harmful components.

Today the X PRIZE Foundation announced the winner of its $25,000 YouTube contest to come up with the next “Crazy Green Idea.” Competitors submitted two-minute videos on what they wanted to see invented. Then 4,000-some YouTube viewers voted on them, choosing the “ultra-capacitor” concept from University of California at Irvine students Kyle Good and Bryan Le.

Here’s more on their electrical storage idea, from the video:

Capacitors recharge in seconds, survive thousands of recharge cycles, and provide high-efficiency electricity by using environmentally benign materials. But here’s the challenge: capacitors are far more expensive (and) provide far less energy than common batteries. We invite the next generation of inventors and engineers to construct an energy storage device far more advanced, far more environmentally friendly, far more affordable than we have yet to see in our lifetime.

Grist thanks its sponsors. Become one.

Watch the winning video:

X PRIZE is the competition-loving group that successfully challenged teams to build private spaceships and offered a still-to-be-claimed $10 million prize for the best mass-producible 100 mpg car. The “What’s Your Crazy Green Idea?” competition was the first of its five to be judged by a popular vote, not an expert panel. The video announcing the winners opens with the line, “The day before it’s a breakthrough, it’s a crazy idea.”

To clarify, the winners didn’t invent anything, they came up with a really good idea that someone else should invent. Which X Prize may “potentially” use for a future prize, at a date to be named later, a spokesperson said. Got that?

Grist thanks its sponsors. Become one.

The winners set the following conditions for developers:

1. You may only use self-contained capacitors
2. You must exceed the energy density of a lead-acid battery
3. The device must recharge in less than a minute and survive 500,000 cycles
4. You must use non-toxic, recyclable materials
5. The device must cost less than two times the cost of a lead-acid battery.
6. The device must hold enough power to drive an electric vehicle for
100 miles per charge