Wind turbine makers have worked hard for many decades now to harness one of the most powerful forces in nature. They have moved from onshore to offshore locations, building ever larger rotors with huge blades, each now longer than a row of 10 London buses. And they’ve stacked those rotors atop dizzying towers, constantly reaching for new, dashing heights.
In their endless quest to capture the most reliable energetic winds, engineers are now moving further out into the ocean to areas of deeper water where particularly strong winds are known to blow. For offshore wind turbines – whose solid-bottomed foundations can only reach 60 meters down – such areas have long been off limits. But a new generation of floating machines seems to be changing that.
The potential premium is huge. According to industry association Wind Europe, 80 percent of offshore wind energy in European waters is in places too deep to make current solid-bottom turbines an economically sensible choice. Deep water, for example, also prevented the installation of large offshore wind farms off the west coast of the US.
Floating turbines can open up large areas of the ocean for electricity generation. But different floating turbine designs compete for cost and efficiency. It’s time to hunt for a winner, given the multibillion-dollar current investment in the floating offshore wind industry and the war in Ukraine that may be accelerating the fossil fuel shift.
There is also added pressure because, despite record offshore wind installations in 2021, the industry is not meeting what it needs to mitigate climate change, according to a new report from the Global Wind Energy Council (GWEC).
The council states that floating wind is “one of the most important game-changers” in the industry. However, the special technical challenges of placing wind turbines on floating platforms, where they have to cope with the harsh forces of stormy seas and unpredictable weather, have led to a surprising variety of possible solutions.
Take the Norwegian company Wind Catching Systems (WCS) for example. The staff there spent five years working on their design for a giant waffle-shaped frame adorned with no fewer than 126 four-rotor wind turbines — like a giant Connect 4 set studded with spinning blades. The entire structure, as high as the Eiffel Tower, would perch atop a floating platform, similar to those used on oil rigs.
Norway plans to install 30 GW of offshore wind by 2040. That would require between 1,500 and 2,000 floating platforms if each carried a single traditional turbine. “We could do it with 400,” said Ole Heggheim, WCS’s CEO. And while the 126 turbines in WCS’s design are only rated at 1 MW each, they are placed so close together that they actually power each other.
Thanks to wind capture systems
This post The race to build wind farms floating on the open sea
was original published at “https://www.wired.com/story/floating-wind-turbines/”