Arup has linked up with Wind Power to continue development of an innovative new 10MW wind turbine design - the Aerogenerator X.
British company Wind Power Limited has unveiled the latest embodiment of its Aerogenerator project, visualised by architects Grimshaw. The Aerogenerator X is twice the power and half the weight of Wind Power’s original Aerogenerator design.
Half the height of an equivalent horizontal-axis turbine, the Aerogenerator X’s weight is concentrated at the base of the structure. Unimpeded by the weight constraints of a normal wind turbine, the blades do not suffer weight-induced fatigue. The Aerogenerator X is considered one of the only real alternative solutions available to help deliver the UK’s offshore wind strategy in a reliable and cost effective manner.
The innnovative design is the conclusion of an 18-month feasibility study called the NOVA project undertaken by Cranfield University, QinetiQ, Strathclyde University, Sheffield University and Wind Power Limited supported by consultant engineers and project managers. The NOVA feasibility project was funded by the Energy Technologies Institute, a public private partnership comprising BP, Caterpillar, EdF, E.ON, Rolls-Royce, Shell, BP, EDF, Eon, Caterpillar, the UK Government and Wind Power.
Speaking at the unveiling of Aerogenerator X Arup director John Roberts said, “despite the installation of a number of large wind turbines offshore, the problems of increasing capital cost for deeper water remains unsolved as does the issue of safe operability in the marine environment. There is a tremendous opportunity for new ideas to make a difference to the commercial viability and operability of offshore wind power. More cost-effective solutions will be essential if offshore wind power is to make the “hoped for” contribution to the UK’s GHG emission reduction targets”.
Cranfield University head of offshore, process and energy engineering Feargal Brennan said, “upsizing conventional onshore wind turbine technology to overcome cost barriers has significant challenges, not least the weight of the blades, which experience a fully reversed fatigue cycle on each rotation. As the blades turn, their weight always pulls downwards, putting a changing stress on the structure, in a cycle that repeats with every rotation – up to 20 times a minute.”
“In order to reduce the fatigue stress, the blade sections and thicknesses are increased which further increases the blade self-weight. These issues continue throughout the device. Drive-train mountings must be stiff enough to support the heavier components inside the nacelle on top of the tower, otherwise the systems can become misaligned and the support structure is also exposed to extremely large dynamic thrust and bending stresses, which are amplified significantly with any increase in water depth”.
“Offshore is the ideal place for wind power but is also an extremely tough environment,” said Wind Power’s Theo Bird. “The US wind researchers who worked on vertical axis projects have always regarded the technology as great to work with at sea because it can be big, tough and easily managed. We are extremely grateful to the ETI who had the vision to help us pick up from where the US left off. By facilitating projects like ours they continue the heritage of great engineering in Britain”.