Modern installations for non-polluting energy production have a dual responsibility to the environment, which can be measured both in terms of their ecology – how efficiently they perform – and in terms of their visual impact upon the landscape. This new generation of wind turbines, developed with the German power company Enercon, addresses both these issues, harmonising the practice’s longstanding interest in developing sustainable forms of energy generation with its broader commitment to exemplary design.
The clarity of the turbine’s design developed through a singular approach to its three principle components, with rotor spinner, ring generator and tower all formed through natural paraboloid geometries. Allied to this formal consistency, the turbine’s engineering is both innovative and highly efficient since the generator is driven directly by its 32-metre-long rotor blades, avoiding the need for a gearbox. Maintenance problems and noise pollution usually associated with turbine gearboxes are therefore avoided. Instead, kinetic energy from the wind is converted directly into regulated electrical current – a far more efficient solution. With an individual power rating of up to 2 megawatts, the resulting turbine can generate enough clean, renewable energy to supply 1,600 homes.
The turbine’s blades are constructed from lightweight glass fibre and epoxy composite – like the wings of a sailplane – while the tower is formed from prefabricated steel units that are light enough to be transported easily and assembled rapidly. Variable rotor speed and blade-pitch adjustment ensure that power yield is maximised, while upturned ‘winglets’ at the blade tips – inspired by precedents in the aerospace industry – allow the turbine to perform efficiently at lower rotor speeds, a factor that helps to create a visually calming effect. The tapering of the 100-metre tower improves the transition of dynamic loads to ground level and also means that the turbine occupies less ground area than conventional turbines of equivalent power output. Taken together, these features enhance the turbine’s integration within the landscape, whether that is in land-based wind farms or in off-shore installations.
“"When we were first told by the council that Swaffham wanted another turbine we did not respond for a little while and the town wrote to us to ask what was happening... It's because everyone there wants another one so much. I'm not surprised it is so popular because, apart from its environmental benefits, it is a beautiful graceful thing... It's very easy on the eye."
Managing Director of Next Generation, the company responsible for the Swaffham turbines interviewed in The Sunday Times, 9 April 2000
“The good news is that wind turbines produce renewable energy, but the bad news is that en masse they look rather like giant earplugs! So our design challenge was to develop these objects into a more acceptable, pleasing form.”
Facts + Figures
- Appointment: 1995
- Client: Enercon GmbH
- Structural Engineer: Ove Arup & Partners
- Quantity Surveyor: Davis Langdon & Everest
- Design Council Millennium Products Award