The Dutch ex-astronaut and physicist Wubbo Ockels, working with the Delft University of Technology, has designed, and demonstrated , an airborne wind turbine he calls a "Laddermill". It consists of an endless loop of kites. The kites lift one end of the endless loop, (the "ladder") up, and the released energy is used to drive an electric generator.
A team from Worcester Polytechnic Institute has developed a smaller scale kite power system with an estimated output of about 1 kW. It uses a kiteboarding kite to induce a rocking motion in a pivoting beam.
The Italian project called "Kitegen" uses a prototype vertical-axis wind turbine. It is an innovative plan (still in the construction phase) that consists of one wind farm with a vertical spin axis, and employs kites to exploit high-altitude winds. The Kite Wind Generator (KWG) or KiteGen is claimed to eliminate all the static and dynamic problems that prevent the increase of the power (in terms of dimensions) obtainable from the traditional horizontal-axis wind turbine generators. Generating equipment would remain on the ground, only the airfoils are supported by the wind. Such a wind power plant would be capable of producing the energy equivalent to a nuclear power plant, while using an area of few square kilometres, without occupying it exclusively. (The majority of this area can still be used for agriculture, or navigation in the case of an offshore installation.)
Balloons can be added to the mix to keep the contraption up without wind, but balloons leak slowly and have to be resupplied with lifting gas, possibly patched as well. Very large, sun heated balloons may solve the helium or hydrogen leakage problems.
An Ontario based company called Magenn Power Inc. has developed a turbine called the Magenn Air Rotor System (MARS). The -wide MARS system uses a horizontal rotor in a helium suspended apparatus which is tethered to a transformer on the ground. Magenn states that their technology provides high torque, low starting speeds, and superior overall efficiency thanks to its ability to deploy higher in comparison to non-aerial solutions. Magenn claims to be putting the first of the MARS product line, a 10 kW model, on the market in 2008. . The first prototypes have been built by TCOM in April 2008