June 6: Floating wind turbine delayed, but ahead of schedule
The tow-out of the HyWind from the Norwegian energy company StatoilHydro was canceled at the last minute. The world's first floating wind turbine will stay a while in a fjord near Stavanger for repair works.
 
There was a cinch in a cable, literally. While attaching the three mooring cables last night, technicians discovered a damaged spot at the last steel cable. The project manager then decided to cancel the planned tow-out of the HyWind on the next day.
 
Communications manager for New Energy, Øystein Johannessen, expects the delay due to the damaged cable will be two weeks at most. According to the official planning, the tow-out was due only in August. So, in all the project is still ahead of schedule.
 
After being towed out to sea, the HyWind will be installed 10 kilometres off the coast of the nearby island of Karmøy, where it will be tested over a period of two years.
 

 
The floating wind turbine consists of a 2,3 negawatt Siemens turbine on a 65 meter high pilon. It has been mounted onto a vertical cilinder that has a depth of 100 meters. The 8 meter diameter yellow submarine floater is made of steel and is partly filled with ballast to stabilise the structure. The hull weighs an impressive 5,300 tonnes, forty times more than the turbine it supports. The entire structure will be moored onto the seabed (between 120 and 700 meters deep) with three cables.
 
Ten years ago (1999) StatoilHydro decided to develop offshore wind for Norwegian deep coastal waters. The company invested 50 million euros in the project. The goal is now to bring the costs back to a level comparable with the offshore turbines grounded in the shallower sandy seabeds.
 
In order to do so, the weight up in the tower should be reduced, Johannessen says. This will allow making the whole structure lighter and therefore less expensive. The firm is therefore looking for lighter wind turbines. These could be direct-drive turbines (without a heavy gearbox) or turbines that have the generator and the gearbox lower in the pilon.
 

 
StatoilHydro's strategy with HyWind is to increase renewable power production, Johannessen explains. With its plentifull hydro power (99 percent of the national power production), Norway is already Europe's main producer of renewable power. It could strengthen this position by adding offshore wind to hydro – which, by the way, is the ideal way to buffer variations in wind power.
 
Apart from increasing power production in Norway, the HyWind could be exported as well. If the company succeeds in getting the price down, that is. Japan, the US and Canada have comparable deep coastal waters and are therefore a potential market.
Two days after the planned tow-out, the HyWind was towed to sea on June 8th. The repairs on the mooring cable had been completed at 2 a.m., after which the floating device was put on its way to the North Sea. From the island Utsira, where we are currently located, the HyWind is visible on the southern horizon.