The Swedish wind power company SeaTwirl has signed a letter of intent (LOI) with Westcon Yards to manufacture and install a commercial-scale 1 MW S2x offshore wind turbine on site in Norway. The agreement is an important step forward in the S2x project.
The steel structures will be fabricated at Westcon’s shipyard in Florø and then transported to Dommersnes Industrial Area for complete assembly and testing. The complete turbine is then towed to Bokn, where it will be installed.
SeaTwirl has been around for a while now. In July 2015, the company first deployed its prototype named S1 off the coast of Lysekil in Sweden. The S1 is a small, 30-kW test version of its floating turbine technology. Rising 13 meters above the waterline and reaching down 18 meters below, it offers energy-producing companies an attractive test platform for offshore wind power and an alternative to diesel generators in remote areas that are off-grid or prone to power outages. It’s been connected to the grid and tested according to plan since its deployment. S1 has withstood harsh weather conditions, autumn and winter storms reaching hurricane wind speeds.
SeaTwirl describes its design as simple and robust, with a minimum of breakable moving parts, which means less downtime and more output. It is a vertical-axis wind turbine that has a high structural limit and can be built larger than horizontal-axis wind turbines.
SeaTwirl is currently developing its first full-scale, 1-MW, S2x unit, which is expected to be commissioned sometime in 2023, for a test period of around five years. The company states that the S2x will be low-cost, less complex, and have less downtime since it has few moving parts, which means more operative hours. It has a stable structure due to the low center of gravity, and the water supports the weight of the wind turbine, which reduces stress on the bearings.
The S2x will reach a height of some 55 meters above sea level and plunge down to 80 meters depths. The turbine diameter is 50 meters, and the rotor blade height is approximately 40 meters. SeaTwirl suggests an optimal operating depth of at least 100 meters and deeper. The wind turbine will cut off power if the wind speed rises above 25 m/sec (90 km/h), but it’s designed to withstand extreme wind speeds up to 50 m/s (180 km/h).
The full-scale S2x could find application in offshore wind farms, Islands and remote locations, and fish farms. Multiple S2xs can be placed in a dense pattern for increased output.
“This is an important step forward in the realization of S2x. We have worked closely with Westcon for a long time to arrange a contract where Westcon can take full responsibility all the way through the installation of S2x. We have great confidence in Westcon and feel that this cooperation will secure not only the production of S2x in 2023 but also strengthen SeaTwirl’s position for future larger turbines,” says Jonas Boström, CTO of SeaTwirl.