An offshore test of floating wind energy technology designed by Norwegian firm, Sway, has resumed, Windpower Offshore has learned.
Sway’s 1:6 prototype has been re-erected off the Norwegian coast and testing has begun. Fine-tuning of the prototype's control system is the current priority, according to the company’s chief executive, Michal Forland.
The prototype was originally installed offshore for testing in March 2011, but sank last November, when wave heights reached 6.3m. The company emphasises that a full-scale model of its innovative design – which would carry a 5MW turbine - would not have sunk under the same conditions, and could operate in waves of up to 30m.
The design developed by Sway is based around a spar anchored to the sea bed and mounted with a downwind turbine. The soon-to-be-resumed test is designed both to help Sway attract potential investors and adjust its control system - which ensures that the structure’s position alters in line with wind direction.
Discussions with industrial firms from Asia that may be interested in commercialising Sway’s design are underway, says Forland. Interest in floating wind technology is on the rise in Asia, particularly in Japan, where some of the country's biggest industrial companies are participating in a government-funded trial off the Fukushima coast (Windpower Offshore 18-Jun-12).
In order to prevent another sinking of the scaled-down prototype, an electrical swivel slip ring has been installed to seal the inlet pipe for the power cable. Such a modification would not be necessary on a full-scale tower, adds Forland.