Last night I caught a brief part of a Horizon programme that talked about how a company is using a kite to generate electricity.
The basic principle is that a glider is launched into the air. As it rises it pulls a tether which turns a shaft connected to a generator, which then turns and produces electricity.
The glider is made by a company called Kitemill.
Kitemill started in 2008 and is based in Voss, in Norway. It’s first commercial orders came in 2015, with five Kitemills ordered for a business park which will supply 22 businesses in Lista.
The demonstration model shown in the documentary was producing 2 kW of energy – about enough to power a house while operating. The model is a 2.8 wingspan kite, really a small glider, connected to a 5kW generator.
The company was raising funds to scale up eventually to a 500 kW model but the next stage is to get to a 30 kW model. This model can start working at wind speeds of over 5 m/s and reaches full power at speeds of 12 m/s. It will have a wingspan of 7.5m with four propellors for vertical take off and landing.
While operating, the winch will feed out at around 4 m/s.
This is still small scale new technology, but a very interesting one. It might see greater adoption in the developing world with fewer restrictions on flying machines.
There is a certain attraction to the idea of gliders flying above businesses generating power, if only because we will be able to look up and see them in the sky.