As wind energy has expanded over the years, engineers have raced to build larger and larger turbines — designed to take advantage of as much wind as possible. But the architect Renzo Piano and an energy company in Italy are trying to make a smaller turbine — one that's suitable for the average yard.
First of all: Why smaller? Because, as you probably know if you leave near a wind farm, those suckers can be loud. And big. Plus, they kill birds. At the basest level, they bring down property values. That's why Enel, the Rome-based energy company, commissioned Piano to have a go at a less invasive turbine. Piano, if you're not familiar, is the Pritzker Prize-winning architect behind some of the most subtle, elegant buildings on Earth (see: This theatre build inside of an old factory in Parma).
Piano describes his design as being based on the physics of dragonfly flight. Unlike standard turbines, which have three blades, it only has two — and when it's at rest, each blade lines up with the central column to diminish its impact on the landscape. The 19m column itself is extremely thin — at only a 30cm wide — which is possible because the blades themselves are almost hollow, thanks to strong carbon and polycarbonite ribbing.
Most commercial wind turbines can handle only a certain speed of wind: Go too high, and an internal computer is programmed to shut it down. Go too low, and the fins can't turn at all. "Drawing the prototype was not easy," Piano comments in a press release, "because it had be an element of a different system to those giants of the past, based on enormous structures." His design takes advantage of the situation by being shaped in such a way that it needs winds of only four miles per hour to harvest energy.
The whole point is to design a turbine that's small and quiet enough to be installed, say, in your backyard — or nearby, at least. And while it's still not clear how close to commercial production they are, the first prototype is currently being tested outside of a Pisa — keep an eye out, if you can find it at all. [DesignBoom]