Don Montague has always known there’s power in the wind. For much of the 1980s, he traveled the world, winning windsurfing World Cup races and thinking up new sail designs. In the 1990s, he turned his attention upward, designing kites to haul surfers across the water at speeds of 40 miles per hour and faster. His experiments helped pioneer the now wildly popular sport of kiteboarding.
In 2006, Montague was well into his latest project, trying to break the trans-Atlantic crossing record using a boat pulled by a giant kite, when his friends, Google founders Sergey Brin and Larry Page (avid kiteboarders both), proposed a different direction. “They said, ‘Hey, Don, we’re working on all these other projects to help save the world—maybe you should focus more on producing electricity than trying to pull boats,’ ” Montague explained over the phone.
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Montague had been trying to get funding from his usual extreme-sport sponsors—Red Bull and sports companies. But now he had a new option, Google, which supplied him with $10 million. The federal government’s Advanced Research Project Agency chipped in another $3 million. Montague approached two kiteboarding scientists, Saul Griffith and Corwin Hardham, of the Massachusetts Institute of Technology, and founded Makani Power, based in Alameda, Calif.  
Airborne wind power has several advantages over traditional windmills. Wind is stronger and more reliable the higher up you go, but building windmills tall enough to get there requires giant support platforms and lots of material. A kite could allow you to harness high-altitude winds much more easily. It would also harness wind more efficiently: 70 percent of the power generated from a windmill comes from the tip of the blade, the fastest-moving part. By flying in a loop, a kite is essentially the most efficient part of the blade, allowing it to gather power more effectively in calm wind.
Kites can also go places regular turbines can’t. Wind power has been growing rapidly in the United States, but only about 20 percent of land in the U.S. is suitable for turbines, and getting access to it can be a mess of land-use negotiations and NIMBYism. Kites have a smaller platform and are less obtrusive than turbines. But their biggest advantage is offshore: winds are stronger and more reliable offshore, but building a turbine platform strong enough to withstand punishing ocean waves and anchoring it to the seafloor is tremendously expensive. Montague envisions Makani’s kites launching from floating platforms far out at sea, harnessing powerful offshore winds on the cheap.
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But the challenges facing kite power are daunting. The kite needs to be sturdy enough that it won’t collapse when the wind changes, but light enough to stay aloft when wind is calm. It has to adjust when the wind changes so it can capture the most powerful gusts. It has to survive turbulence, rain and lightning. It has to be able to take off and land on its own. Montague laid out more challenges for Makani: they had to work with the Federal Aviation Administration, conduct studies on the impact on birds, coordinate with local airmen whenever they tested, design a tether that was strong enough to hold the kite but could also conduct electricity back to the ground, and design a way for the kite to automatically land itself if the tether broke. “The kite was just 5 percent of the problem,” says Montague. “It was so huge and we had to work on everything at once.”
Montague doesn’t have a background in science or engineering—growing up dyslexic in Vancouver, British Columbia, he says he barely made it through high school. But he excels at solving problems, and goes about it with manic energy. When he was designing kitesurfing sails, he was testing 300 prototypes a year. He would sketch out plans on early computer-aided design (CAD) programs, send them to China to be built, test them three days later when they arrived, and send back a tweaked design immediately. “I can fix something and fly it and tell you what’s wrong in the first two seconds, intuitively,” he says. “Sometimes I’d already come up with a better design before FedEx arrived, but didn’t matter,” he says. “It’s just a process of momentum.”
He went about designing power kites the same way. “Makani was just a matter of bringing people together to solve a particular problem and keeping them focused,” he says. Makani’s engineers worked on multiple challenges at once, testing frequently and constantly returning to the drawing board. For an early flight test in 2008, Montague says engineers stayed at the company’s test site in Maui, Hawaii, 24 hours a day for six months straight, having food brought in, and obsessing over their aircraft. “Everything was fun,” he says of the early design process. “Everything is solvable. You always find a way. We always win—some problems just take a little bit longer.”
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What they ended up with looks more like a carbon fiber propeller airplane than a kite. It launches from a raised platform, hovering vertically into the air using propellers on its wings. Once it catches the wind, it begins to fly in wide loops, the propellers now functioning as wind turbines, generating power that gets transmitted back to earth through a conductive tether. It does all this, by the way, on its own, using an autonomous navigation system designed by Makani.
Last May, Makani’s 30-kilowatt kite successfully completed its first autonomous flight. Next year, Makani will start testing a 600-kilowatt system, with a wingspan of 85 feet. Eventually, Montague sees fields of massive megawatt kites circling overhead and feeding power back to the grid. “We’ve been working on this a long time,” he says, “we’re getting to stage where it is reality.” Still, he cautions, the days of widespread commercially viable kite power are a ways off. “We’re not doing this for money. We’re doing it to make a difference.”
Makani suffered a tragic loss last year, when its beloved CEO and co-founder, Corwin Hardham, died unexpectedly at his desk of a heart attack. He was 38, and, Montague says, in perfect health, surfing every day. Montague stepped in as interim CEO and arranged for the company to be absorbed into Google’s X Lab, its secretive skunkworks that designs projects like Google Glass, high-altitude Wi-Fi balloons, and cars that drive themselves.
Montague is now back to focusing on the kite boat project he was beginning when Brin and Page directed his attention to clean energy. When I speak with him, he has just returned from a test in the Bay (35 knots in only 10 knots of wind, he says approvingly). But his boat shop is right next door to Makani Power, in a decommissioned naval air station in Alameda, and he’s still involved with Makani’s projects. He’s optimistic about its future. He sees kites being adopted first by islands, where importing power is expensive, and then by countries with lots of offshore wind, and then everywhere. “I don’t think anything will stand in the way of making this happen,” he says, before correcting himself: “It is happening.”
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