1September2010
Extracting energy from winds at altitude
Posted by Cecilia under: Energy.
The Macani Power Inc. company in Alameda, CA is developing Airborne Wind Turbines (AWT) to extract energy from powerful, consistent winds at altitude. Makani AWTs will produce energy at an unsubsidized real cost competitive with coal-fired power plants, the current benchmark of the lowest cost source of power.The Macani wing and a conventional wind turbine operate on the same aerodynamic principles.
The Macani wing is transformed into a kite by tethering it to the ground. The aerodynamics remain the same but the wing can harness the energy in the wind by pulling against the tether. The onboard avionics computer navigates the wing in a circular path that mimics the tip of a wind turbine blade.
The advantage of the Macani wing lies in the effectivity. The tip of a wind turbine is the most effective part. In some cases the last 25% of the blade is responsible for 75% of the energy generated. The Macani wing captures all of the benefit of the blade tip using a fraction of the material. At a wingspan comparable in length to one wind turbine blade, the Macani wing can move higher in the sky and access 10x as much energy.
Energy is extracted from the Macani wing with small rotors driving high-speed generators. The electricity is transmitted to the ground via conductors in the tether. There it is converted to grid-quality power and connected to the grid.
On the website of Macani Power you can see the Macani wing in motion with all technical details. It is an interesting and innovative new idea around wind energy.