Crosswind kite power

Crosswind kite power is power derived from airborne wind-energy conversion systems (AWECS, also AWES) or crosswind kite power systems (CWKPS). The kite system is characterized by energy-harvesting parts flying transversely to the direction of the ambient wind, i.e., to crosswind mode; sometimes the entire wing set and tether set are flown in crosswind mode. From toy to power-grid-feeding sizes, these systems may be used as high-altitude wind power (HAWP) devices or low-altitude wind power (LAWP) devices without having to use towers. Flexible wings or rigid wings may be used in the kite system. A tethered wing, flying in crosswind at many times wind speed, harvests wind power from an area that exceeds the wing's total area by many times.

Crosswind kite power systems have some advantages over conventional wind turbines, including access to more powerful and stable wind resources, a high capacity factor, capability for deployment on and offshore at comparable costs, and no need for a tower. Additionally, the wings of the CWKPS may vary in aerodynamic efficiency; the movement of crosswinding tethered wings is sometimes compared with the outer parts of conventional wind turbine blades. However, a conventional traverse-to-wind rotating blade set carried aloft in a kite-power system has the blade set cutting to crosswind and is a form of crosswind kite power.

Miles L. Loyd furthered studies on crosswind kite power systems in his 1980 work "Crosswind Kite Power".[1] There are crosswind advocates who believe that crosswind kite power was introduced by P. Payne and C. McCutchen in their patent No. 3,987,987, filed in 1975;[2] however, crosswind kite power was used far before such a patent, e.g., in target kites for war-target practice, where the cross winding power permitted high speeds to give practice to gunners.[3]

US3987987figs
This illustrates where parts of the wing set of a crosswind kite power device is cross winding during conversion of the wind's kinetic energy.
Crosswind kite power station with separate motion transfer with two wings offshore, artist's impression.
Drawing from patent US 3,987,987.
Scheme of some types of airborne crosswind power systems
BenjaminTignerFig5US8066225 Farming crosswind kite power devices is illustrated by Benjamin Tigner.
Lifter of human by use of fast-motion autorotating bladed crosswind kite power system, a gyro kite type.
As George Pocock controlled his kite system wings to left or right, he would gain power because of the crosswind kite power energy-gain effect.
Kite-Wahnsinn am Silvaplana See. The crosswind kite power systems shown has a purpose to move the athlete fast downwind, upwind, and sometimes into the air to significant altitudes and distances. The wind is slightly slowed by such activity, as the CWKPS harvests energy from the wind. Kiteboarding.
  1. ^ Lloyd, Miles L. (1980). "Crosswind Kite Power" (PDF). Energy. 4 (3). Retrieved 2023-07-10.
  2. ^ Payne, Peter R. "Self-erecting Windmill". Retrieved 2023-07-10.
  3. ^ "U.S. Navy Target Kite". Retrieved 2023-07-10.