Vertical axis turbines could change floating offshore market

SeaTwirl Vertical Axis Floating Wind Turbine. Credit: SeaTwirl

Swedish turbine manufacturing company SeaTwirl has received patent approval on its vertical axis wind turbine (VAWTs) design from the Chinese and US patent authorities.

There is growing demand in China for energy and wind power expansion, especially as the government has set goals for the environment. Consultancies predict that offshore wind power is expected to increase in China by more than three gigawatts annually between 2022-2027.

CEO of SeaTwirl, Gabriel Strängberg, commented “the Chinese market is the one that stands for the most expansion of wind power in the world, and floating wind power will also be included in the future expansion, which makes it important to protect our technology even there.”

The VAWTdesign allows the generator and bearing house to be replaced just above the water surface by boat, cutting installation and maintenance costs as well as minimising downtime.
In April, SeaTwirl won the backing of Beligum’s Colruyt Group as well as offshore logistics company NorSea to build a 1MW prototype of its floating VAWT. The project, estimated to cost SEK70 million (USD7million), will be built in 2020 in Norway and will be called the S2 prototype.

The idea came about after a five-year USD4.1 million study by US based Sandia National Laboratories was published in 2018, found that VAWTs could potentially cut the costs of floating offshore wind turbines installation and maintenance by eliminating the need for gearboxes, high speed shafts, yaw systems and nacelles, all of which are subject to faults.

As costs reduce and sites for offshore wind farms in shallow waters become more sparse, the floating offshore wind industry is expected to gain popularity in 2020.

VAWTs are also insensitive to sudden changes in wind direction, known as wind veer, and, according to a joint French study, between Nenuphar Wind and Adwen offshore, can be placed on top of each other to improve performance and reduce caballing. This makes VAWTs a good solution for cramped environments, such as lakes.