Flying kites for the environment
This Norwegian high-altitude power generation technology was inspired by extreme sports
Photo courtesy of Kitemill
Kitemill looping during power production in Lista, Norway. This composite photo shows the path of the kite in a crosswind.
Rasmus Falck
Oslo, Norway
Kitemill is a technology-based startup in the Airborne Wind Energy market. The pulling power of kites can whip up boards of fun and thrills, but it can also be harnessed to generate electricity. In November the founder will be one of the international speakers at the Energy Harvesting and Storage conference at the IDTechEx in Santa Clara, Calif.
It all started when founder Thomas Håklau was inspired by the activities at the Extreme Sport Week in his hometown of Voss in Western Norway. Ekstremsportveko is the largest sport and music festival of its kind and is hosted every year. They host competitions in kayaking, rafting, mtb-bmx, skateboarding, skydiving, paragliding, hang-gliding, multisport, freeride, big air, climbing, BASE, and longboarding. For a whole week in June athletes compete and challenge themselves.
Inspired by the sport of kitesurfing, the entrepreneur wondered why he should not apply the same principal for making energy. Along with technologists from Kongsberg, one of Norway’s key high-tech industry towns, he has tested the energy potentials of several prototypes and developed a computerized control system. This work has been supported by the SkatteFUNN tax incentive scheme since 2009 and has also received support from Clean Energy for the Future and Innovation Norway. According to the entrepreneur, such support is important in getting projects off the ground and triggering private funding, which is necessary in relation to international competition.
High-altitude wind energy is based on a large kite moving up and down at high altitude. Anchored to the ground and lifted by a 100-meter-long arm, the kite is connected by wires to a winch on the ground, which is connected to a generator producing electrical power when the kite makes it move at an altitude of 600-800 meters. The winch concept is inspired by technology used on fishing trawlers, and simulations show that the system uses about 2 percent of the produced energy to pull the kite back. A kite could cover the energy needs of two or three homes using just ordinary wind conditions.
Kite turbines harness forces mainly using tension, as compared to the compression and shear forces that act on a windmill. The way in which kite turbines handle the forces allows the same capacity to be achieved with less than 20 percent of the materials compared to a conventional onshore windmill. Since kite turbines can reach high altitude, it no longer matters if the plant is located in an offshore, coastal, or even inland area.
According to the entrepreneur, the kite concept has many advantages compared to conventional wind turbines. The kites use much less material, have no need for rotor blades or concrete towers, and can reach better wind conditions at higher altitudes. And situated on the ground, the generators and other moving parts can easily be accessed and maintained.
This article originally appeared in the Nov. 6, 2015, issue of the Norwegian American Weekly. To subscribe, visit SUBSCRIBE or call us at (206) 784-4617.
