In the future, adding more clean energy to the grid could be as simple as launching a glider or flying a kite — if Makani Power and other companies like it can become commercially viable.
Makani, based in Alameda, California, is at the forefront of an emerging pack of inventors, as many as a dozen in the United States, eight in Europe and four in Asia. The companies are building airborne kite-like devices that are designed to capture wind energy with their propellers. The companies typically launch the devices up as high as 2,000 feet.
While most of the work is out-of-the-garage prototyping, Makani provides a lone exception of a company that has landed venture capital. To date Google.org has invested $15 million, and the Department of Energy’s the Advanced Research Projects Agency-Energy has invested $3 million.
Over the summer, Makani Power made news with the maiden flight of its Wing 7 prototype, an airborne glider capable of generating 20 kW with a wingspan of eight meters, or just over 26 feet. The glider is designed to capture wind energy with its propeller at altitudes exceeding 1,000 feet and relay it by tether to the ground.
“It is important to the overall U.S. airborne wind energy effort that Makani Power is successful in carrying out the work for the grant awarded” says PJ Shepard, secretary for industry group Airborne Wind Energy Consortium, and a spokesperson for California-based Sky WindPower, another company developing such a glider.
One hurdle the nascent industry has to surmount, as most emerging technologies and industries do, is regulation. The Federal Aviation Administration is currently weighing a decision as to whether to allow such tethered gliders to operate. So far a ruling appears at least a year away, Shepard said.
For its part, Makani to date has burned through most of its working capital, and is nearing completion of its 18-month ARPA-E grant-funded pilot project. And while the nascent industry awaits an FAA ruling, investors have been skittish of sinking capital into technology.
Sky WindPower was named by TIME Magazine as one of the top 50 top inventions of 2008, but has yet to land investment capital; Dmitri Cherny, founder of energy glider developer Highest Wind, was the darling of New Hampshire’s Speed Venture Summit in 2009, only to come away empty-handed from scores of meetings in venture capital circuits in New Hampshire and South Carolina.
“There have been only a few limited proofs of aspects of whole concepts because these are expensive undertakings requiring more than just angel and vc support,” Shepard said. “As with development of all new energy supplies and the systems to support the capture of energy that have preceded this new energy field, governments will have to provide additional support.”
Whether justified or not, the current environment for that kind of support doesn’t look encouraging. The emerging clean tech sector now faces a more skeptical public and congress in the wake of the bankruptcy of the solar panel company Solyndra. And DOE and ARPA-E’s loan programs are under investigation by the department’s inspector general.
Nevertheless, Cherny has filed for a small government grant and says he plans to move his company to Lake Marion in South Carolina this spring. Airborne devices generate “a lot of electricity at a minimal impact,” he said.
Highest Wind’s glider would rise about 1,200 feet into the sky like a kite on a string, and generate electricity as it rises and falls on the winds, its tether turning a flywheel on the ground. The glider could produce a daily power output of 30 kilowatt hours.
Cherny believes farms would be a good market for his product. They typically use more than 150,000 kilowatt hours of electricity per year.
With a few proof-of-principal flights, other parts of the government are slowly warming up to the idea of funding these flying kite-type of inventions.
The Department of Defense has awarded WindLift in Raleigh, North Carolina two grants for development of its mobile technology, a 20 kW mobile airfoil. One grant was made in 2009 and another was made this past April.
David J. Olinger of Worcester Polytechnic, a pioneer of airborne wind energy technologies who is largely credited with the laying out the concepts of the field, recently captured a three-year National Science Foundation grant.
Olinger said patents for such gliders were first filed in the 1970s.
His lab has demonstrated proof-of-principal by putting a glider in the air. Following on these flights, his students started a project called Kite Power Wiki that focuses on low-cost kite power systems for developing nations, but his group has not been able yet to develop a system practical enough to commercialize.
