Wind turbines are an important part of the electricity mix in the near future. The biggest disadvantage on earth is their unstable energy production, so developers are increasingly moving them to coastal waters for stronger and more stable winds. In addition to higher initial investments, however, they hit the technological limit – the pole can be anchored only at depths of up to 60 meters, in practice they are no further than 30 kilometers from the coast.
Hywind, which opened its first floating wind farm about 40 kilometers off the coast of Aberdeen, Scotland, bravely struggles with the problem. It consists of six turbines with a heavy conical base that keeps the column in an upright position. Such equipment can be moored at depths of up to 900 meters.
Installation of a floating turbine by a giant floating platform. Scheme of anchoring to the seabed. The actual thickness of the anchor ropes is impressive.
The concept proved to be viable. Hywind Power supplies 36,000 British households and has set several new performance records.
The Norwegian company Wind Catching Systems intends to move the same idea forward, but with a fundamentally different technology. The concept of the column and blades, which is based on medieval windmills, is being replaced Wind Catcher (windcatching.com), a gigantic system of 126 propellers of various sizes.
At 310 meters, the structure is taller than the Eiffel Tower. The upper floors of the rotors are thus exposed to faster winds. Large conventional “pinwheels” (the world record holder has leaves 118 meters long) can only be operated up to a certain wind speed, then there is a risk of destruction. For significantly smaller propellers (the longest blade on the Wind Catcher is 15 meters), the marginal wind speed is higher. This and the total area of the blades means that the system will produce 400 gigawatt-hours of energy under ideal conditions – five times more than today’s largest and most powerful conventional wind turbine.
Smaller propellers are easier to manufacture, transport and maintain – it is not necessary to shut down the entire system to service a single unit. Operator access is provided by a simple lift and a system of sidewalks. Expensive specialized equipment, such as floating platforms used to install power plants, is not required for installation or major service interventions (see one of the photos above).
The first generation of wind farms from the 1990s is coming to an end and composite blades are difficult to recycle, so they accumulate in landfills. Wind Catcher sheets are aluminum, ie completely recyclable. The manufacturer predicts a service life of 50 years, which is about twice as long as conventional turbines.
The first Wind Catcher will go into pilot operation in the North Sea, promising theoretical parameters have taken hold in California, Japan and elsewhere. It is now “only” to verify the practice. Production is scheduled to begin this year, with the first Wind Catcher coming to sea in 2023 or 2024.
Do you like an even wilder project?
If you like bold technology projects, there is more North Sea Wind Power Hub, which surpasses anything that has emerged around wind turbines so far. In 2018, the Dutch company TenneT came up with the idea of an artificial island in the shallows of Dogger Bank (about 125 kilometers from the British coast in the North Sea). It is intended to serve as a service center for giant wind turbines.
The island will be surrounded by thousands of turbines, together to supply 30 GW of energy to 80 million people in Germany, the Netherlands, Denmark and Britain. On an area of 6 km2 there is a planned airport, port, accommodation for staff and even a park with a lake. It should be done as early as 2027.