Jason Halpern's parents own a vineyard. Seven years ago, they wanted to install solar panels to power one of their buildings, but they couldn't: the roof was heavily shaded and the fields around the buildings were reserved for planting. Halpern was just in high school at the time, but he believed the cause was not lost. "Farmers already harvest solar energy," he says. "They just do it with plants."

Now 23, Halpern believes he has a solution: the PowerFlower, a solar device that resembles a five-foot-tall metal flower. The device relies on concentrated photovoltaic technology (CPV): in this case, the mirrored "petals" focus the sun's rays onto a rod that is covered with tiny solar cells. CPV has been used successfully in large-scale industrial installations, but it can also be scaled down and made portable.

During the day, the Power-Flower can be connected to irrigation pumps, lights, electrical fencing, or other equipment. The unit is light enough to be hauled away on a hand truck, which may also make it useful for war zones and disaster areas.

Halpern and his partner, Patrick Murphy, say the device may cost between $5,000 and $10,000. Hook up three in a row and you've got enough juice to run a small irrigation pump.