Picture a large kite soaring high in the sky, connected to the ground by a long cable. Now, imagine if the energy generated by its movement could be stored, distributed, and used. Well, you can stop imagining, because this is exactly what Kitepower offers: a new way of producing renewable energy from wind that’s already here. While the concept is quite different from the typical futuristic wind turbine we’re used to, it’s already being tested successfully in Ireland.
The way it works is simple: The kite, roughly 60 square meters in size, rises to over 400 meters—for reference, the Eiffel Tower is about 300 meters tall—and begins tracing figure eights in the sky to maximize traction. That pulling motion turns a drum, which converts mechanical energy into electricity that’s stored in batteries. And it’s being tested now? Yes. In western Ireland, Kitepower, a Dutch company and spin-off from Delft University of Technology, has already demonstrated power outputs of around 30 kW per kite and full battery charges of 336 kWh.
Why did they choose Ireland as a testing ground?
The Atlantic coast of the Emerald Isle, particularly County Mayo, offers a unique combination of intense and consistent winds, low population density, and vast, open peatlands. These features make it the perfect natural laboratory for testing this technology. A couple of years ago, the first testing site dedicated to airborne wind power began operating near the town of Bangor Erris. This project is the result of a collaboration between Kitepower, energy company RWE, and the county council, with support from the European Union.
Its technical operation is easy to understand: the kite flies in crosswind mode, which increases both lift and pulling force. During the traction phase, also known as the reel-out, the cable unwinds and pulls a drum, activating a generator at the ground station. When the kite reaches its maximum extension, the system releases the wing's tension and brings it back over the base. This begins the recovery phase, or reel-in, where the cable is wound back in, using only a fraction of the energy generated during the traction phase. The net difference between these two phases is the amount of usable electricity produced. In Irish tests, a typical cycle consists of 80 seconds of traction and 20 seconds of recovery, and the flight is automatically controlled from the ground.
What are the advantages?
The professionals running the tests emphasize that the best thing about this method is how simple it is. Another advantage is that it can operate at height. Flying at 400 meters allows the kite to capture stronger, steadier winds than a typical ground-based wind turbine. This is why developers argue that the energy yield per unit of installed material is potentially higher.
The material requirements also change dramatically: without a tower or gondola, steel and concrete use drops sharply, and the entire ground station can fit into a standard container (the wing and its control unit together only weigh a few dozen kilograms). In practice, this means easier logistics and far less civil engineering. Another advantage over traditional turbines and wind turbines is speed. According to the team in Mayo, the system can be assembled in about 24 hours. It doesn’t require expensive foundations, which makes it much easier to bring renewable energy to places that turbines or power grids can’t reach.
Their initial applications are precisely in areas where renewable energy is hardest to deliver: islands, remote villages, or temporary sites. A single kite of around 30 kW, paired with a battery, can meet essential electricity needs, recharge electric machinery, and replace noisy diesel generators that rely on imported fuel.
Kitepower is one of several related technologies, including flexible wings with ground-based generators, rigid wings with onboard turbines, and other alternative designs. The concept doesn’t stop at the air—the kite can also be used underwater. In fact, the Swedish company Minesto has launched the Dragon 12, a 1.2 MW device that traces figure eights in tidal currents and is already supplying electricity to the Faroe Islands’ grid.
To make this technology widely usable, there’s still work to be done on certification and aeronautical safety, managing airspace, coexisting with birds, improving the durability of the wing and cable, and bringing the cost per kilowatt-hour down compared to diesel or conventional wind power. Despite these challenges, the Irish pilot project has a clear target niche: generating electricity where the grid doesn’t reach or where it fails. If the tests prove that the kites are reliable and cost-effective, we may soon see them working in pairs and integrated with batteries and solar panels in microgrids, providing backup in emergencies or helping decarbonize islands and remote areas. It’s not magic; it’s engineering capable of giving us a new kind of renewable energy that, quite literally, comes straight from the sky.