by Alex Elder
Makani Power, acquired by Google X in 2013, is seeking to improve the modern wind turbine design in order to make wind power more efficient, cheaper, and less intrusive. Makani has developed an innovative new system of utilizing wind as a source of energy by using an “energy kite.” These kites are actually carbon fiber gliders which fly in circles while remaining tethered to the ground. This design allows the energy kites to reach higher altitudes than traditional wind turbines while significantly reducing the cost of materials for construction. Due to their lightweight design, the kites are more aerodynamic, and thus more energy efficient, than ground-based wind turbines. Because higher altitudes allow access to stronger and more consistent wind speeds, the kites can generate about 50% more energy than traditional wind energy technology.
The kites are first launched from the ground station by rotors which act like propellers on a helicopter. Once in the air, the kite generates power by flying in large circles where the wind is strongest. Air moving across the rotors mounted on the kite forces them to rotate, driving a generator to produce electricity. This power then travels down the kite’s tether to the grid below. The tether itself is made of conductive wires and connects the kite to a ground station. In 2013, Makani Power demonstrated that these energy kites can even complete the launching, circling, and landing process entirely autonomously, meaning that the system is generally low-maintenance as well.
These energy kites can even operate over the ocean, where winds are stronger than on land. Having an energy kite tethered to a floating object like a buoy or a boat would solve many of the problems associated with off-shore wind farms which must be mounted on the sea floor. Overall, this innovative idea opens the door to a more energy-efficient and cost-effective system of harvesting wind energy.
Anderson, R. (2015). Wind turbines take to the skies to seek out more power. BBC News. http://www.bbc.com/news/business-31300982
Makani Power. http://www.google.com/makani/solution/