Will airborne wind energy ever take off?

Since Google’s parent company, Alphabet, dropped wind power business Makani from its Moonshot Factory, a decades-long debate has been reignited about the commercial viability of airborne wind energy

Only four percent of the world’s electricity comes from wind energy, partly because engineers have struggled to scale the technology in a cost-effective way. Airborne wind energy could be the solution

In renewables, airborne wind energy has often been dismissed as pie in the sky. So when power-generating kite company Makani joined Google’s research and development organisation, named X, in 2013, industry experts saw the acquisition as a sign that the technology could finally enter the mainstream. Makani emerged from the innovation lab in February 2019, partnering with Royal Dutch to expand offshore. It held its first test flight in Norway in August that year, but in February 2020, the project was abruptly shut down.

“It was a surprise for all of us,” said Udo Zillmann, Secretary General of Airborne Wind Europe. “There were no signs before.” The axing of Makani from Google’s portfolio has shaken the airborne wind energy industry, a niche corner of the wind power sector that is still in the early stages of research and development. It came as a surprise, not least because Makani had been the industry’s crowning glory for some years. “They were clearly the most advanced company in our field,” Zillmann told The New Economy. “Unlike other products, their 600kW turbine worked for a long time and they were also the first ones to scale up to such a big device.”

So far, no airborne wind company has developed a commercially viable product – even those that have been in business for over for a decade

Ever since engineer Miles Loyd first communicated his vision for a “flying wind generator” in his 1980 paper Crosswind Kite Power, commercial viability has continued to elude the airborne wind energy sector. But despite the many setbacks the technology has experienced, its advocates are convinced the long-term investment is worth it.

The green light
Unlike traditional wind turbines, airborne wind turbines have no tower. Makani’s product, for example, is attached to the ground with a flexible tether that allows it to sail in the air like a kite while its eight spinning rotors generate energy. These turbines can reach high altitudes, where the winds are faster and more consistent. “To give you a sense of how fast these winds are, think of kite surfing,” said Zillmann. “You just feel this power that pulls you through the water.” According to a 2012 study from California’s Lawrence Livermore National Laboratory, high-altitude winds alone could provide 100 times the global energy need.

But today, only four percent of the world’s electricity comes from wind. While this is partly due to wind’s unreliability, it’s also because engineers have struggled to scale wind energy in a cost-effective way – a problem that solar power, by comparison, has overcome.

“If you think back 20 years ago, solar was incredibly expensive,” said Zillmann. “It was truly a luxury. You could use it in space and maybe in your calculator – a very small space – but it was impossible to put it on your house roof. And now it’s as cheap or cheaper than wind turbines in most places around the world.” While the cost of wind power has dropped 50 percent since 2010, solar power has fallen 85 percent.

Some believe that airborne wind turbines could be the answer to wind’s scalability problem. In one study, Zillmann found that half of the cost of a turbine is in the material used to build the tower. The generator that produces the electricity accounts for just three percent of the total cost. Without the need to build massive structures, the cost of wind power could be drastically reduced.

Getting off the ground
In addition to Makani, several other start-ups are competing in the airborne wind energy sector, including EnerKite, Skypull and Ampyx Power. Some of these companies, like Skypull, plan on starting small, providing airborne wind turbines to small, off-grid farms. Others have plans to go large from the beginning by supplying energy to remote systems like mining operations.

Makani’s products in numbers:

Enterprise model


Year designed


Rated power

Wing 4 model


Year designed


Rated power

M600 model


Year designed


Rated power

So far, however, no airborne wind company has developed a commercially viable product – even those that have been in business for over a decade. One of the reasons for this slow progress is that the technology requires long-term testing. “Before we can sell a product, we have to be able to show that you can put it in a field and it can work for 20 years, like a wind turbine or a solar panel,” said Zillmann.

The technology itself also has some limitations, which makes financing difficult to secure. Airborne wind turbines may be able to produce energy more cost-effectively and reach areas that ordinary turbines can’t, but they’re relatively small products. “Although airborne [wind energy] does have an advantage over traditional offshore floating, its limited power capacity in megawatts can be an issue as it’s competing with offshore turbines which will be reaching 15MW [or more] soon,” said Leila Garcia da Fonseca, Senior Manager of Wind and Solar Operations and Maintenance at Wood Mackenzie.

With these challenges in mind, many have their doubts about the technology’s future. “Full commercialisation is still distant,” said Garcia da Fonseca. “Considering that airborne lags behind traditional wind technology, I think it’s fair to say that we’ll see some pilot projects being developed in the next few years but not at utility scale, at least not during this decade.”

A flight of fancy
It seems that Alphabet, Google’s parent company, finally ran out of patience with Makani. Its closure was the first Alphabet had made since founders Larry Page and Sergey Brin stepped back from management roles in December. “After considering many factors, I believe that the road to commercial viability is a much longer and riskier road than we’d hoped and that it no longer makes sense for Makani to be an Alphabet company,” said Astro Teller, the so-called ‘captain’ of the Moonshots Factory, in a statement.

A decade ago, Alphabet would have paid little mind to the commercial viability of its moonshot projects. But since then, its finances have come under increasing scrutiny from the company’s board. In 2019, Alphabet lost $4.8bn in its Other Bets business. For new CEO Sundar Pichai, dropping the project may have seemed an obvious move amid pressure to cut costs.
“If somebody at Alphabet asked, ‘when will this pay dividends?’, the answer would of course be, ‘not this year, not next year and maybe not in 10 years’ time’,” said Zillmann. “It’s a long-term development for the whole industry.” This automatically raises questions about whether the technology is really worth the wait.

Nevertheless, by making wind energy more affordable, it could play an important role in the future of renewable energy. By 2030, the EU expects renewable energy to provide 32 percent of its electricity, and wind power is key to reaching this target. “Our latest forecast shows that nearly 77GW of annual wind power capacity is expected globally from 2020 to 2029,” said Garcia da Fonseca. With governments setting ambitious targets for carbon neutrality, the incentive to crack airborne wind energy is surely greater than ever.

Alphabet may have given up on Makani, but this decision should be considered in light of its broader business goals, namely cost-cutting and generating reliable sources of income. Elsewhere, airborne wind energy start-ups are making progress. Norwegian company Kitemill plans to set up the first airborne wind energy farm in the south-west of the country in 2021. Though Google’s X seems to have lost some of its enthusiasm for moonshot projects, start-ups in this space are still prepared to play the long game.