Marine wind turbines are part of the solution to our energy problems. But future offshore wind farms will be both larger and further from land than we are used to. This will present technical challenges.
Wind farms with over 100 turbines will be no rare sight in the future. But the larger numbers of turbines will force the farms further out to sea. They are being moved out so as not to spoil the view for people living along the coast. At the same time the marine environment needs to be taken into consideration. And naturally, it will still be important to select locations with good wind conditions.
All this presents a number of completely new economic and technical challenges. Establishing wind farms further away from land increases the costs of erecting the turbines and of providing cables back to land, and in particular the requirements for equipment and expertise rise markedly in water depths exceeding 25-30 m.
GEO has been involved in pilot studies for all the large Danish offshore wind farms. From the first scheme, Vindeby, with 11 turbines and a total capacity of 5 MW to Horns Rev with 80 turbines and a total capacity of 160 MW. Denmark is currently a world leader in the production of wind energy and generates approx. 20 % of the total Danish electricity consumption. Abroad, GEO has played a part in seismic and geotechnical studies for Swedish offshore farms such as Lillgrund (in Øresund) and Utgrund (in the Baltic) and for planned British and German wind farms.
Massive expansion The plans for offshore wind farms in Northern Europe over the next few years are imposing. In Denmark, two major projects are under way, namely Horns Rev II and Rødsand II. And in Sweden, Germany and the UK there are also big expansion projects planned for the coming years. In the UK alone it is planned to erect some 1700 turbines by 2012.
Conditions at many of the planned locations put extra requirements on skills and equipment. The locations have shifted from the previous under 20 m of water up to 30-40 m water. GEO has equipment which is geared to the new challenges. Not least as a result of its many years with site investigations for offshore installations in the oil/gas sector.
