Enercon E70 Turbine

Each wind turbine will have a three bladed rotor and nacelle mounted on a cylindrical steel tower. Typically each wind turbine will have a mast height of 64.5m and blade radius of 40m and a maximum overall height to blade tip of 100m.

Important Note : The exact make and model of wind turbine within this tip height envelope can not be specified at this time. However the wind turbine proposed for the scoping report and the subsequent Environmental Impact Assessment is the Enercon E70 2.3MW model, with a 64.5m hub height and a 71m diameter rotor. The machines would be delivered to site in pre-assembled major component form.

In common with the majority of operating projects in the UK, it is proposed that in order to minimise reflection from the turbines, they would be finished with a midgrey colour with a minimum-reflective, semi-matt coating.

Enercon E70 wind turbines start to generate when the wind speeds at the nacelle reach 2m/s, attaining their maximum output (rated capacity) of 2.3MW at 16m/s. Between 2 and 16m/s the turbine will produce varying amounts of power depending on the wind speed. Under severe weather conditions i.e. wind speeds above 28 - 34m/s (equivalent to 10 - 12 on the Beaufort scale, and described as gale to hurricane-force), the turbines would automatically shut down to protect the equipment.

In the Enercon E70 wind turbine, the rotor is connected to the generator without a gearbox. Power cables pass down the inside of the turbine tower to a transformer housed at the foot of the tower that will convert the generation voltage (usually 690V) to the local electrical distribution network voltage (in this case likely 33kV).

The wind turbines are fully automated by a computer controller. Wind sensors mounted on the nacelle of each turbine continuously detect wind speed and wind direction. The turbine rotor is continually moved to face into the wind by a yaw drive in the base of the nacelle.

All key operating parameters (e.g. oil pressure, temperature, vibration) are monitored by the turbine itself, and also remotely by the operator. Should any parameter, of any turbine, go beyond normal operating limits, the wind farm or turbine will immediately inform the operator who will either restart the site remotely should it have shut down, or send out operations personnel to investigate and rectify the fault on site.

The wind turbines will be serviced annually, during which operations personnel will check the integrity of the structure, the mechanical systems and the control system functionality.

During normal operations personnel will visit the site approximately once a week, in a light van or four-wheel drive vehicle.