About SeaTwirl

Here you can learn more about the future and the history of SeaTwirl and reflect on past developments.


About SeaTwirl

Interview with the CEO, Gabriel Strängberg (In Swedish)


Future and History

SeaTwirl has a clear vision for the future. The company is in the process of developing the 1MW rated capacity SeaTwirl S2 which is scheduled to be completed by 2020. Our ambition is to sell our first commercial unit to a leading energy company and then establish a small floating offshore wind farm in 2025.



SeaTwirl is now in the process of developing the next unit SeaTwirl S2, with a rated capacity of 1MW. More information about SeaTwirl’s S2 wind turbine can be found in the “Technology – SeaTwirl S2” section.

Below is a depiction of the company’s next wind turbine, SeaTwirl S2.

SeaTwirl S2


SeaTwirl started the development of the company’s so far largest unit, SeaTwirl S2.
SeaTwirl was listed on Nasdaq First North on the 22nd of December. More information about the shares can be found under Investor Relations.



SeaTwirl’s S1 prototype was launched in the Lysekil test lab in July and shortly thereafter it generated power.
More info about the SeaTwirl S1 can be found in the “Technology – Test Lab Lysekil, SeaTwirl S1” section.

Below is a depiction of the company’s next wind turbine, SeaTwirl S1, installed in Lysekil.

Portfolio SeaTwirl liftes by Crane

Portfolio SeaTwirl Sunny Day


The location of “Test Lab Lysekil, SeaTwirl S1” was approved by the County Administrative Board.

An aerial picture from the location of ‘Test Lab Lysekil, SeaTwirl S1’
The construction of the SeaTwirl S1, with a total length of 30 meters and a turbine diameter of about 10 meters, began. The rotor blades for the SeaTwirl S1 have now arrived and the tower and parts are currently being painted and inspected.

Parts of the tower are undergoing painting and inspection.

Delivery of the rotor blades for Test Lab Lysekil, SeaTwirl S1 is now completed.

Gabriel Strängberg was hired as the Managing Director. He will also be part of the technical team and involved in the development of the next prototype, SeaTwirl S1.

The company, SeaTwirl AB, is formed to continue the development of the next floating wind turbine.

A successful testing and installation of the prototype P3 was carried out in the sea near Halmstad on the Swedish west coast.

Intense weeks of installing, launching and testing in the sea proved that the prototype worked exceptionally well. The prototype P3 was connected to the electrical grid and managed to survive in harsh weather conditions, withstanding winds of up to 19 m/s in rough sea.

SeaTwirl Prototype III Pictures of the installed SeaTwirl prototype P3 near Halmstad on the Swedish west coast.
To evaluate, learn and develop further an in-depth analysis of the prototype P3 tests were carried out.

Successful tests were performed at SSPAs wave basin facility during the spring of 2011. The results proved that SeaTwirls floating wind turbine concept is stable even in very harsh weather conditions.

The company Ehrnberg Solutions corp. was formed to develop SeaTwirl’s floating wind turbine technology and an initial board of directors was formed. More theoretical analysis and predictions were performed and the construction of SeaTwirl prototype P3 began.

A prototype P2, with a total height of 8 meters, was successfully tested outside the port of Halmstad on the west coast of Sweden. The tests showed satisfying results but further in-depth analysis is required.
Tested during 2009
Picture from 2009 of SeaTwirls P2 prototype being tested.

In 2008 much of the theoretical work was performed to evaluate how SeaTwirl’s floating wind turbine would perform at a larger scale. The results from the evaluation were encouraging and indicated that upscaling would lead to a reduced cost per MW and significantly reduced hydrodynamic friction losses from the underwater structure.

The first prototype P1 was successfully tested in a lake in Småland, located in the south of Sweden. It verified the principle of using the waters buoyancy force to carry the weight of the wind turbine, which significantly reduced the loads on the bearings located inside the generator. The turbine proceeded to spin for some time even when the wind had stopped blowing.

In 2006 the inventor of the concept Daniel Ehrnberg started to think about how the buoyancy force of the water could be used to relieve the mechanical loads on bearings on a floating wind turbine and may even provide a form of rotational energy storage source, like a flywheel.

The principle could be used for a floating vertical axis wind turbine. This idea and concept looked promising after some initial estimations. The concept was verified in a water tank experiments during 2006.