Giant towers, tall as football fields, have become a prerequisite to maximizing wind-turbine power production.
But Altaeros Energies, a Massachusetts company with its roots at MIT, is putting down the pipe and sending turbines aloft using a helium-filled, inflatable shell that looks like a Macy's Thanksgiving Day Parade float. And it also looks like it might work.
The company said [PDF] it scored a major breakthrough last last month when it tested a 35-foot scale prototype of the Altaeros Airborne Wind Turbine (AWT) in Maine, producing power at an altitude of 350 feet—which just happens to be the height of a conventional tower.
But 350 feet is only the beginning for Altaeros, which is really looking to tap into winds more than 1,000 feet above ground.
The company believes it can trim the cost of wind power by 65 percent by accessing high-altitude winds that it says blow steadier and fives times stronger than the winds that today's tower-mounted turbines rely on.
The Boston-based startup also touts the ease and flexibility of putting the turbine aloft.
"For decades, wind turbines have required cranes and huge towers to lift a few hundred feet of the ground where winds can be slow and gusty," Bell Glass, inventor of the AWT and Altaeros CEO, said in a statement. "Modern inflatable materials can lift wind turbines into more powerful winds almost everywhere—with a platform that is cost competitive and easy to set up from a shipping container."
Altaeros said the technology it uses to send up the AWT is adapted from aerostats, "industrial cousins of passenger blimps that for decades have lifted heavy communications and radar equipment into the air for long periods of time." And these are tough customers—unlike Kermit the Frog in 1985—rated to withstand hurricane-strength winds and with mechanisms that bring them slowly back down to earth, Altaeros said.
For the recent test flight at the Loring Commerce Center in Limestone, Maine, Altaeros used a prototype fabricated in partnership with Doyle Sailmakers of Salem, Mass.
It carried a Southwest Skystream turbine, and produced "over twice the power at high altitude than generated at conventional tower height," Altaeros said.
The company believes an immediate market for its system could be outposts—military bases, rural villages—that now rely on diesel generators for power. Longer-term, it believes its dramatically lower scale-up costs make it right for offshore power generation.
Last fall, Altaeros won the ConocoPhillips Energy Prize, given in recognition of new ideas that can help improve the way that energy is developed and used in the United States. And that wasn't the only airborne wind turbine to gain notice in 2011. Makani Power, with a flying airplane-like design, won Popular Mechanics' 2011 Breakthrough Innovator Award in the Energy Category.