Going aloft for wind power

In another twist on wind power, inventors are designing kites and balloons to generate electricity.

The wind industry is undergoing rapid growth as utilities, prompted by government incentives, seek out cleaner sources of power generation. Typically, these commercial-grade projects involve large wind turbines, which stand 100 to 400 feet high.

Kites and balloons are not widely used, and they face some of the same challenges as traditional wind turbines, such as bird deaths and complaints over location. But that isn't stopping people from coming up with "flying" wind generators.

One company, Magenn Power, intends to build a helium-filled balloon that resembles a giant cog wheel.

As the wind passes over it, the system generates electricity through an onboard generator. Power is transferred to the ground via its tethers, according to company Chief Executive Mac Brown.

The advantage that high-flying machines have over traditional wind turbines is that balloons can benefit from more steady air flow, Brown said. The company's Power Air Rotor product would fly at 1,000 feet.

Magenn, which is seeking $5 million in initial funding, intends to sell a 4-kilowatt system to remote villages in Pakistan and India that don't have electricity. Over time, its plan is to develop systems that are tied to the electricity grid to customers in North America and Europe.

"The value proposition we have is getting wind power anywhere," Brown said. "With turbines, you have to site them on coastal or high-wind areas."

Kites, too, are making a go at more than recreational flying.

A company called KiteShip has developed a kite designed to help motor a commercial ship. The kite, whose largest size would be bigger than a football field, can cut a ship owner's fuel cost and pollution emissions by 20 percent, according to the company. A similar system is under development at Germany's SkySails, which says its oversize kite will be pulling a cargo ship sometime this year.

An Italian sensor manufacturer has proposed the Kite Wind Generator Project (KiteGen), which also aims to capture the power of high-altitude wind.

The research project imagines that power plants could be created with kites attached to a giant revolving "merry-go-round" structure.

Briza Technologies, meanwhile, has proposed what it calls the Hovering Wind Turbine, which is also meant to capture faster, high-altitude winds.

The idea behind the hovering turbine is that it would be used as an alternative to turbines in offshore wind farms.

Another advocate of capturing the force of faster winds is Sky WindPower. The company proposes that systems be placed in altitudes of 15,000 feet, according to the company Web site.