Take to the Skies: Wind Power Goes Airborne

Nigel David, Feb.10,2016 

Wind turbines take a lot of flak for making noise, casting shadows, and killing birds. Lots of people still don’t want them in their backyard. But there is another reason why the iconic structures are suboptimal. They cannot be made tall enough to tap into the stronger and more consistent winds that exist at higher altitudes. The largest wind turbines stand at over 200 meters tall now, but these massive towers and blades can be challenging to transport and install.

These are things the new guard of wind enthusiasts point to when touting the new breed of wind energy conversion devices: airborne devices. Picture a tethered kite or a glider lifting off from the top of a shipping container. In some designs, like Google's Makani, electricity is generated via turbines on the aircraft; in others, a ground based generator is driven by the oscillating tension on the tether while the craft flies in a figure of 8 type pattern, hundreds of meters above the ground.

Kiteboarders can appreciate the wind at altitude. Much to the dismay of the surface based windsurfers, kiters can have fun when the winds are relatively light on the surface. Two of the speakers at the January 26th event are avid kite surfers. Aad Havermans, of Ampyx power, and Grega Verdinik of Fluxtec. They have had first hand experience with the power if the wind up there and could not ignore its potential. The Fluxtec device is heavily influenced by the kites used in kite surfing. As an aeronautical engineer, Grega worked on optimising kite designs prior to starting Fluxtec.

Our third speaker and moderator for the event was Sonny Banjak. I’m not sure if he does extreme wind sports, but he specializes in getting renewable energy projects going in the extreme climates up north. He is representing TwingTec, a Swiss based company with a rigid wing design similar to Ampyx.

Both the Twingtec and Ampyx systems are based on a rigid wing glider design. Twingtec will focus on the off-grid community and resource market where the competition is with expensive diesel generated electricity. They estimate this market to be worth about 1 billion dollars. They plan to be testing a 100 kW device by 2018 and a 500 kW unit by 2020.

Ampyx has an equally ambitious roadmap with a similar timeline that ends with the production of a 2 MW device. The aircraft will have a 40 meter wingspan. They plan to be cost competitive with other independent power producers and sell power to the main electricity grids.

In what I see as a smart move, Ampyx has been working closely with the European Aviation Safety Agency to develop new standards for this class of aircraft, similar to what is happening with drones. If Ampyx is on the leading edge of designing to these standards, they will be in a strong position in the industry. With these aircraft flying at altitudes approaching 500 meters, there will be no getting around the air space legislation without proper certification.

When asked about the main challenges of achieving reliable power generation with these devices, Aad, Grega and Sonny named off a few: establishing operation and maintenance requirements, gaining market acceptance, and achieving a low crashes/hours of operation record. There are still many other unknowns with this technology, but with continued vision, investment and ingenuity they will be overcome. If nothing else, it would be neat to be able to deploy a “power kite” from atop a camper van.