The energy system we are developing is sometimes referred to as a wing, sometimes as a kite. More formally we refer to it as an Airborne Wind Turbine (AWT). The Makani system operates on many of the same principles as a conventional wind turbine. The ‘blade’ of the Makani system is a wing that, instead of being fixed to a hub, is anchored to the ground by a tether such that it is free to fly in large circles in the vertical plane across the wind. The blade is effectively following the same path as the tip of a conventional turbine, however on this larger path, the entire wing flies at the same speed as the aerodynamically active tip of a wind turbine blade, thus greatly enhancing the effectiveness of the wing. In addition, the wing is capable of flying at greater heights than a conventional turbine, allowing it to access winds that are stronger and more consistent. The energy density of the wind is proportional to the cube of the wind speed, and hence the energy increases rapidly with wind speed. The combination of these two advantages enables the Makani AWT to deliver about twice the energy of an equivalently rated conventional wind turbine.
AWTs deliver about twice the energy of conventional turbines per unit of capacity by:
Delivering greatly enhanced light wind performance.
Accessing winds at altitude that can offer twice the power density.
AWTs are much less capital intensive. They contain about 20 tons of material per MW which:
Eliminates the need for large foundries, forges and casting facilities
Greatly reduces the need for extreme load transportation to the site
Creates a shorter, more flexible local supply chain that scales rapidly.
AWTs are economically conducive to siting in a wider array of areas such as:
Lower quality sites where wind is insufficient for conventional windmills
Dips and hollows unsuitable for other types of wind energy
Offshore in either deep or shallow water with minimal support structure.