How a system extracts energy from the wind and transfers energy to useful purposes helps to define types of crosswind kite power systems. One type of parameter regards the position of the generator or pump or tasking line or device. Another type of parameter regards how the tethers of the tether set of the kite system are utilized; the tethers holding the kiting wing elements aloft may be used in various ways to form types; tethers may simply hold working wings aloft, or they may be pulling loads on the ground, or multitasking by sending aloft-gained electricity to ground receivers or by pulling loads or by being the tasking device itself as when used for pulling people or things or cutting or grinding things. Some types are distinguished by fast motion transfer or slow motion transfer. Typing of crosswind kite power system also occurs by the nature of the wing set where count of wings and types of wings matter to designers and users; a wing set might be in a train arrangement, stack configuration, arch complex, dome mesh, coordinating family of wings, or just be a simple single-wing with single tether. Types of crosswind kite power devices are also distinguished by scale, purpose, intended life, and cost level. Typing by economic success occurs; is the system effective in the energy or task market or not? Some CWKPS are a type called lifters; they are purposed just for lifting loads, perhaps humans; the type is frequented by the use of auto rotating blades that appear then to look like helicopters. A single crosswind kite power system (CWKPS) may be a hybrid complex performing aloft energy generation while also performing ground-based work through tether pulling of loads. The crosswind kite power systems that involve fluttering elements are being explored in several research centres;
flutter is mined for energy conversion in a few ways. Researchers are showing types of CWKPS that are difficult to classify or type.
Tether pulling of people or goods on boards, in hulls, with skis, etc. In the systems of this type of CWKPS, the pulling tether set drives the resisting people and objects to various points on the surface of water bodies or land or points in the atmosphere. In this type of crosswind kite power operation, the design of the resistive objects (people, boards, hulls, boats, ships, water turbines, air turbines, other wings) makes for further types. Cross winding of the upper flying wings provide power to achieve certain final objectives. The objectives are found in such as kiteboarding, kite windsurfing, snow kiting, yacht kiting, freighter-ship sailing, kite boating, and free-flight soaring and jumping. A collection of researchers have explored the historic free-flight parakite realm to where crosswind flying of the systems' wings would enable free-flight in the atmosphere; fundamentally this is a kite-string set with a wing above and a wing as the resistive anchor set; control of the separate wing set, especially in cross winding efforts mine the power of winds in different layers of the atmosphere.
Tether pulling to drive generator or pump shafts In the systems of this type, an electrical generator, pump, or tasking line is installed on the ground. There are two subtypes, with or without a secondary vehicle. In the subtype without a secondary vehicle, the "Yo-Yo" method, the tether slowly unwinds off a drum on the ground, due to the windward pull of the kite system's wing, while the wing travels crosswind, that is, left-right of the wind's ambient direction, along various paths, e.g., a figure-8 flight path, optimized
lemniscate paths, or circular paths (small or large radius). The turning drum rotates the rotor of the generator or pump through, perhaps, a high-ratio gearbox. Periodically, the wing is powered, and the tether is reeled in, or, using the crosswind for a constant pull, the tether is re-connected to a different section of the drum while the wing is traveling in a "downwind" cycle. In some systems two tethers are used instead of one.
Onboard generator In the systems of this type, one or more flying blades and electrical generators are installed on the wing. The relative airflow rotates the blades by way of
autorotation, an interaction with the wind, which transfer the power to the generators. Produced electrical energy is transmitted to the ground through an electrical cable laid along the tether
Motion transfer with upwind ground receivers In this type an electrical generator, pump, tasking line set, or lever is installed on the ground upwind of the wing and driven by the operation of two or three or more tethers arranged from a fast-moving cross winding flying wing set. Examples are found in the research centres of several universities and kite-energy research centres.
Lighter-than-air (LTA) assisted twin-coordinating wing sets Several research centres are exploring twin wing sets employing tether pulling of upwind ground-based loads where the cross winding wing sets use lighter-than-air devices to assure flight in case of lulls in the ambient wind.
LTA-kite-balloon-lofted fast-moving autorotating bladed turbine with upwind receiver of electricity Many in-public-domain patent disclosed teachings and some current research centres are with a focus on using LTA kites to hold bladed turbines using autorotation to drive flown generators.
Flutter-based crosswind kite power systems, fast-motion method When a wing element in a kite system is designed to have
flutter occur, that fluttering may be harvested for energy to power various loads. In flutter, the wing element travels to crosswind and then reverses to travel to crosswind in a generally opposite direction; the frequency of cycles of reversed direction is high. Flutter in traditional aviation is usually considered a bad and destructive dynamic to be designed out of an aircraft; but in CWKPS, flutter is sometimes designed into the kite system for the specific purpose of converting the wind's kinetic energy to useful purposes; the fast motion of flutter is prized by some kite-energy systems development centres. Harvesting the energy of flutter in kite systems has been done in several ways. One way is to convert the flutter energy into sound, even pleasant sound or music; purposes vary from entertaining one person or a crowd of persons; bird-scaring has been an application. Jerking tether lines by the kite-flown fluttering elements to drive loads to make electricity has been done and is being explored. Pumping fluids by use of flutter-derived energy has been proposed in the kite-energy community. And having the fluttering wing made with appropriate materials and arrangement to be a direct electric-generator part, then electricity can be generated immediately; part of the fluttering wing that is formed to be a
magnet flutters by conductive coils forms the parts of the
electric generator.
Traction by use of CWKPS CWKPS are used to move objects immediately over ice, snow, land, ponds, lakes, or oceans. The movement of objects may be done for various reasons: recreation, sport, commerce, industry, science, travel, mine-clearing, defence, offense, plowing, landscaping, etc. The multitude of kite systems flown to crosswind to move kite boarders, land sailors, kite surfers, kite boaters, yachts, ships, catamarans, kayaks, power kiters, kite buggies, kite skiers, kite water skiers, etc., is keeping kite-wing manufacturers busy.
Sky Sails is a leader in saving fuel in the shipping industry by using CWKPS.
Lifters using CWKPS In this type of CWKPS the fast-motion of the flying blades or wings harvest the wind's energy to power the lifting capacity of the system. Mass loads are sometimes close-coupled with the wing set; at other times the mass lifted is distributed along the tether set. A military use of this type involved
rotor kites tethered by the kite line; a human observer gets lifted to high points for observation purposes. Some of these were used in conjunction with submarine operations with the submarine's towing motion providing the apparent wind for the CWKPS. One example is the
Focke-Achgelis Fa 330. Lift-and-place or lift-and-drop uses occur in this type; mass loads are lifted and then placed or dropped; this is done sometimes to overcome barriers or to save ground-transportation fuel costs. When the mass that is lifted is a generator coupled with the crosswinding blades, then the AWES type is changed; this change is the foundation for the focus of some current wind power companies.
Torque transfer via rotary tether sets CWKPS In this type, a set of kites is grouped to form a rotor, the rotary cross wind kites drive their set of tethers around a shared axis. Rings are set inside the rotary tethers to assist in holding the tethers apart. The tensile lines then transfer torque from the rotating kites to a ground based generator. On 15 December 2015 this method was the first to successfully complete the someawe.org 100*3 challenge For a prototype demonstration see ==Theory==