As wind turbines are designed and constructed to ever increasing sizes, so the component sizes must increase in proportion. In the case of the blades, for MW scale machines, handling and transportation start to become major problems since, for example, the road clearance beneath bridges is no longer sufficient. One solution would be to design blades in sections which were then assembled on site. Such a technological development would also facilitate the exploitation of remote sites, especially those with complex terrain. However, it is of prime importance that structural integrity and blade performance are not diminished by the connection between different sections and that any extra costs incurred by the design are less than the subsequent savings.
This project therefore proposes to take a comprehensive look at possible connection designs - developed from state of the art blade root connections and more innovative light aircraft wing joints - to test the most promising, and then to design and build a prototype sectional blade. This would then be tested for both static and fatigue strength and the results compared with the equivalent conventional blade design. The implications for manufacture, transportation, construction, and blade repair will be fully assessed and included in an assessment of the cost effectiveness of the concept. The main innovation, therefore, will be to produce a modular blade design and to demonstrate its reliability with respect to strength (static and fatigue) and to evaluate the possibilities for reducing the costs of installed blades. The project brings together a new partnership from four different countries: the Danish wind turbine blade manufacturer, LM Glasfiber A/S, the structural integrity section of the German research establishment, DLR, the wind turbine blade testing group of TU Delft in the Netherlands, and the Energy Research Unit of RAL in the United Kingdom.
It is anticipated that by the end of the project the partners will have produced a connection assembly design fit for incorporation in very large blades, together with an assessment of the circumstances under which the concept would be cost effective.
Such an understanding is a useful prerequisite to the successful integration of large wind turbines (> 1 MW) in the European landscape (onshore and offshore) and also to further expansion into overseas markets.
Funding SchemeCSC - Cost-sharing contracts
2600 GA Delft