Sway said the test turbine, which was launched early this year, was only designed for a maximum wave height of 4 metres. Data collected by NREL showed wave heights of 6.3 metres.
According to the company, a full-size version of the model would be able to withstand wave heights below 26 metres. It was installed in March. Sway Turbine, a sister company of Sway, is developing a 10MW turbine that could use the floating platform.
The test model sank after water entered the tower through the inlet pipe for the power cable, causing the tower to fill with water. Sway said the turbine had suffered "no visible damage" and would be brought to the surface.
The aim behind building the 1:6 test was to help raise investment as well as technical verification. Sway’s model uses a pole anchored to the seabed while the tower tilts at 5 degrees. The tilting mechanism allows the tower to hold a larger turbine.
Additionally the structure uses a downwind rotor, tilted in the opposite direction and so that it is continually lined up with the wind.