A 13-kilometre underwater cable from the world's first large-scale floating turbine has been installed and tested off the southern city of Stavanger. Upon commissioning of the turbine, power will be sent ashore from power company StatoilHydro's HyWind turbine to the municipality of Royrvika and be delivered to local grid operator Haugaland Kraft.
The turbine was installed in water depths of 220 metres off the coast of Norway in June. The pilot project aims to test the technology over a period of two years and at a cost of NOK 400 million (EUR42 million) (Windpower Monthly, July 2009). "We've worked this summer on mooring the floater to the three seabed anchor points as well as laying and testing the cable," says StatoilHydro's Sjur Bratland. The work was carried out by Nexans and Siemens under observation by StatoilHydro.
In July, the team tested the turbine's rotor blades, which are about 80 metres in diameter. Further testing will continue until early September. StatoilHydro expects the turbine to begin generating power in late September or early October.
With conventional turbine foundations becoming expensive at depths of 30-50 metres, most offshore development is limited to shallow near-coast waters. The goal of testing is to obtain information and data for continued development and to reduce costs.
Meantime, offshore proponents hope HyWind will create new opportunities for the wind sector by giving developers greater flexibility in siting projects. Oyvind Isachsen of the industry group Norwegian Wind Energy Association believes Hywind may one day prove a game-changing technology on a global scale. "They are made for Japan (and other) areas where they don't have any shallow water - where you have depths of 150 metres," he says.
In terms of total installed wind capacity, Norway ranks behind its neighbours, with 436 MW compared to 3.2 GW in Denmark and 1 GW in Sweden. But a law proposed in June by the ministry of petroleum and energy seeks to establish a framework for offshore wind that would identify maritime areas suitable for development, pending environmental impact assessments. The proposed act also lays out regulations for applying for concessions, installation, operation and de-commissioning of offshore plants and electricity transmission.