With the turbine tower and nacelle in place, the next stage of the installation was to lift the 30-tonne wind turbine generator and fix it to the nacelle.
The generator is a direct drive generator. This means that there is no gear box to speed up the main shaft and it is, therefore, a very low rpm generator. Thus, for the generator to perform effectively, it has to be of a large diameter. This particular generator is approximately 5.5 metres in diameter. This can present an issue with respect to transporting these things to site, due to their weight and width – although they can be transported vertically.
The photographs below show the installation sequence.
The wind turbine generator was first lifted from its horizontal position on the delivery vehicle into a vertical orientation, ready for it to be fixed to the nacelle at the top of the turbine tower. Once installed, the generator will be sandwiched between the nacelle and the rotor hub.
The generator was then lifted by the 1000-tonne crane up towards the turbine tower. A 1,000 tonne crane was required due to the reach required over the top of the existing chicken sheds
As it approaches the top of the turbine tower (below right), the wind turbine generator has to be manoeuvred with extreme precision. Once again the human element (below right) is crucial with respect to the precise lining-up and positioning of the generator prior to it being securely fixed to the nacelle. Interestingly the generator is also being guided from the ground, although the ropes are barely visible in the photograph.
With the sun going down, the final picture shows the generator being held in place whilst it is securely fixed to the nacelle.
The turbine tower sections, nacelle and generator were all installed in a day.
Tomorrow morning the hub and rotor blades will be attached to the generator.
Are you considering a wind turbine project?
The first step to develop any wind power site is to conduct a full Wind Turbine Feasibility Study.