For fixed bottom mounted offshore wind concepts state of the art is to use jackups or crane vessels for assembly and installation operations. Sufficiently sized equipment that can operate under most weather conditions needs to be chartered increasing the cost of the wind park. In case of undersized equipment a considerable delay during the installation phase can be expected. Even if the costs of the tower and the nacelle will slightly increased in case of our invention the total costs of fabrication installation maintenance will be reduced. Reverse installation of the tower will allow for the lowering of the rotor and the nacelle to a position where smaller construction vessels can be used for heavy maintenance or repair of the wind turbines.
In order to reduce installation an manufacturing costs we are developing an offshore windmill incorporating with three innovative features; a U-shaped pontoon a telescopic tower and a rotor that can be tilted in horizontal position. Other than this the product will use standard parts as being used in today’s wind turbine designs. By using the telescope function the nacelle and rotor can be lowered closer to the sea level and by additionally tilting the rotor in the horizontal position the nacelle can be lowered even further. The technology can be handled by already established work procedures used by the offshore service industry and deploying our system will lead to several benefits: - Lower centre of gravity allows for towing a relatively slender tower to the installation area - The turbine can be assembled using onshore cranes in sheltered water - Use of smaller cranes and installation vessels will represent a considerable cost saving element