Wind turbines used for power generation work best when they’re large and mounted up high where wind speed is higher. This is not an aesthetically appealing proposition, but it’s the only way wind power makes sense on the large scale right now. A French company is trying to change that with a contraption called the Wind Tree. As you might guess, it’s an array of wind power turbines in the shape of a tree, and several of them will be deployed in Paris this coming March as a test.
The Wind Tree is being developed by NewWind and has 72 artificial leaves. Each one is a vertical axis turbine, vaguely conical in shape. Because each one has little mass, they can generate power with a gentle breeze as slow as 2 meters per second (4.4 mph). This could make the Wind Tree useful for generating power, on average, 280 days of the year. Total power output across all 72 turbines is estimated at 3.1 kW. Larger traditional turbines can produce considerably more power, but they need more wind to get going and thus operate fewer days of the year.
At 11 m (36 ft) tall and 8 m (26 ft) in diameter, the Wind Tree is about the size and shape of a real tree, and images of the prototype actually do look rather nice. It could probably pass for a decorative sculpture in an urban setting. It’s made entirely of steel, and NewWind says it is completely silent during operation. All the cables and generators are sealed inside the steel structure. It can be plugged into the public grid, or used to supplement the power of a particular building or complex.
Each Wind Tree is expected to cost €29,500 (US$36,500), but could pay for itself in a few years. The real advantage here is that cities could install “groves” of Wind Trees at ground level to harvest power. The neat design could help avoid the public opposition that wind farms sometimes cause.