When most of us think balloons, we think, "I never should have had children." But these solar balloons are a lot more promising than their carnival counterparts. Constructed of photovoltaic fabric, the soft tank is filled with helium and tethered by power wire above a home, saving space on the ground while optimizing sun exposure. But it's not just the physical footprint that makes the technology so appealing. It's the price per watt.
Because while $10,000 of traditional solar panels will produce a a kilowatt of energy over 25 square meters, the solar balloon power equivalent costs just $4,000. The engineers' biggest concerns seem to be wind resistance, as they're still finalizing the optimal design.
On the downside, the balloons will require moderate yearly maintenance (we're not sure what that entails). But simultaneously shutting up your child and producing clean energy has to involve a catch somewhere. [inhabitat via dvice]