The ‘typhoon-proof’ wind farms powering China’s coast

Both on-land and offshore wind turbines need to be typhoon-resistant if they are installed in areas exposed to the weather phenomenon, but the feature plays a more crucial role for offshore ones because typhoons are much stronger at sea, says Xiaoli Guo Larsén, a professor at the department of wind and energy systems at the Technical University of Denmark.

Standing tall

Major Chinese companies have increased their turbines’ resilience using a combination of strategies, according to Han. They include developing advanced materials, improving their weather-forecasting ability and upgrading turbines’ control systems, she says.

A good example, according to Han, is a model called OceanX manufactured by China’s Mingyang Smart Energy Group.

With a floating foundation, the OceanX model supports not just one but two turbines. The main reason behind the unique design is to increase the platform’s output. Compared to a single turbine whose blades swipe across the same area as OceanX’s two turbines combined, OceanX can generate 4.29% more electricity, according to Mingyang. This is because the two turbines’ blades spin side by side in opposite directions – one clockwise and the other anti-clockwise – so the wind between them will blow faster, enabling more electrical energy to be converted from air kinetic energy, the company says.

But the floating platform also has plenty of intriguing features to counter typhoons and stay balanced during extreme weather, says Wang Chao, the turbine’s chief designer. For example, its foundation is tied to the bottom of the ocean by ropes via one single point underneath it. This allows the structure to change its orientation more easily to be aligned with the wind. “As long as the turbines face the typhoon, the load (forces) they take will be the smallest and they will be the safest,” Wang says.