Floating wind turbines prove robust in extreme weather conditions

Atlas details that the groundbreaking success of the WindFloat Atlantic project highlights the advancements in offshore wind technology.

The WindFloat Atlantic project, the first semi-submersible floating offshore wind farm globally, is situated off Portugal's coast and features just three turbines. Since its commissioning in 2020, it has surpassed expectations by generating a total of 320 GWh of electricity, enough to power around 25,000 homes annually. Fully integrated into the grid, the wind farm consists of three floating platforms, each equipped with an 8.4-MW Vestas turbine.

These semi-submerged platforms are anchored 328 feet (100 meters) below the surface with chains and are connected to a substation in Viana do Castelo, Portugal, via a 12.4-mile (20-km) cable. In 2022, the project generated 78 GWh of electricity, with production rising to 80 GWh in 2023. The Vestas turbines used in the project are notable for their impressive scale and power. Each turbine features a blade diameter of 538 feet (164 meters) and can reach tip speeds of up to 232 mph (373 km/h), producing 66,000 volts DC.

The nacelle, which alone weighs 375 tons (340 tonnes), is the largest offshore wind turbine in the world. Semi-submersible floating wind farms have the distinct advantage of being deployable in deeper waters where traditional bottom-fixed turbines cannot operate, as they are limited to depths of approximately 150-200 feet (50-60 meters). 

These floating platforms can be situated further offshore, where winds are typically stronger and more consistent, enhancing the turbines' efficiency compared to land-based systems. Their partially submerged, three-legged design with active ballast systems provides greater stability in rough seas, further boosting their performance. 

From 2011 to 2016, the WindFloat Atlantic project tested a 2-MW prototype at sea, which successfully generated electricity for five consecutive years, even withstanding extreme weather conditions, including winds of 69 mph (111 km/h) and waves of 55 feet (17 meters). This successful trial paved the way for the installation of the full-scale 25-MW system. In 2023, the WindFloat Atlantic demonstrated its robustness by enduring a severe storm with winds reaching 86 mph (139 km/h) and waves up to 65 feet (20 meters).