'We are going back to the essence of wind energy'

Wind fulfills an essential function in our energy supply, there is little doubt about that. However, the construction of wind farms is complex and costly. In some cases, kites offer an inventive alternative here. Delft-based Kitepower is developing kites that generate wind energy cost-effectively. The engines that power these kites are produced by maxon. Johannes Peschel, CEO of Kitepower, and Francis De Wilde, account manager at maxon, talk about their collaboration, the current applications and the future potential of this fascinating system.

The potential of pilots

Kitepower was founded in 2016 by members of a research group at TU Delft, which had previously been founded by famed Dutch astronaut Wubbo Ockels. The headquarters is still in Delft, while the test site for the kites is in Ireland.

"Kites are the world's most compact and mobile system for generating wind energy," Peschel explains. In fact, besides a kite, Kitepower's installations consist only of a ground station in a container and a Kite Control Unit (KCU). The kites are therefore used, among other things, on construction sites, where diesel generators are often the only way to generate electricity. Kitepower's installations offer an alternative to this that is just as mobile, but which can greatly reduce polluting emissions of CO2 and nitrogen. It also eliminates the need to transport fuel. "Kitepower thus fills the gaps in the supply of wind energy," Peschel said. 

In the future, the company wants to develop on-shore wind farms in locations where construction of conventional wind farms is not possible. In the long term, off-shore wind energy also offers great potential. After all, kites can generate energy on floating platforms, where the depth of the sea is not an obstacle, as is the case with the construction of offshore wind turbines. Eventually, the price of kite electricity could drop to as little as two cents per kilowatt-hour, Peschel concludes, because it requires so little mass. "We are going back to the essence of wind power generation, and the potential for that is enormous."

An impressive engine

Since its inception, Kitepower has been working with maxon, which develops the KCU motors that control the kites when they are in the air. maxon is a Swiss company and has a facility in Enschede, the Netherlands, with its own R&D team that supports customers in development. The products are distinguished by high power density and high precision. maxon's four business units focus on aerospace, medical technology, industrial automation and mobility solutions.

In the search for suitable motors, Kitepower tested several motors. Not every motor is suitable just like that. Maxon's motors stand out for their size and robustness, says Peschel: "The motors are very compact, but they drive a kite that pulls tons of weight. That's very impressive to see." The kites can sometimes make hard landings, but that poses no problem for the engines. In addition, Peschel appreciates maxon's service: the company stays involved and offers information and support even after the purchase. Moreover, because maxon also has an R&D team in the Netherlands, there are short lines across the technical axis.

Several years ago, maxon developed a new, fully integrated motor combination. With this, the modifications that Kitepower previously still had to make to the engines are a thing of the past. maxon helped Kitepower integrate the new engines. "It is also instructive for maxon to continue working with our customers after the delivery of our engines," concludes De Wilde: "Not only do we learn more about how our engines can be used, Kitepower also offers us inspiration to work on interesting and socially relevant projects."