Whitehouse Burn Turbine

• Maximum output is 800 kW
• Over the year the total production is estimated at 2.4 GWh, enough to power approximately 510 homes [1]
• The turbine is direct drive, and has no gearbox
• Cut out wind speed is 28-34 m/s (62-76 mph)
• It starts producing electricity in wind speeds of 3 m/s (6.7 mph, a light breeze)
• The turbine was designed by Norman Foster, the world renowned architect
• At this site the turbine is predicted to save approximately 1000 tons of carbon per year [2]

The turbine shown on the left is an Enercon E48, the same model proposed at Whitehouse Burn. It was installed near Keith, Moray, in August 2011. The photograph is taken from approximately 1.2 km from the turbine, from an elevation of 120 m with the turbine base at an elevation of 230 m. This is a similar perspective to the Whitehouse turbine when driving along the B8001. Click on the photo for a larger version.

The turbine recently installed (October 2011) at Glyndebourne Opera house in Sussex is the very similar Enercon E44, with the only difference being slightly smaller blades (22 m as opposed to 24 m). You can see a video of its construction.

Construction process

Care has been taken to calculate the impact of the construction on local roads and traffic. The turbine itself is delivered in 6 lorries, which are classed as abnormal loads. It will be delivered out with of peak traffic times and in convoy (2 x 3 vehicles) to minimise disruption. Additional construction traffic will include approximately 30 loads of concrete of normal HGV size. The scale of this construction traffic should be compared to the number of HGV loads generated by commercial forestry operations which after a large forest block has been felled would considerably exceed this number.

As part of the construction process the access track will be upgraded for 550 m within the forest. This improvement is required independently of the turbine construction in order to extract timber from the woodland.

Turbine noise

Noise produced by turbines can be categorised as mechanical noise (produced within the turbine) and aerodynamic noise from the blades rotating. This model of turbine does not have a gear box - a significant source of mechanical noise. The noise produced by wind turbines is dependent on the wind speed. Calculations show that the wind turbine noise levels at all residential properties comfortably meet the ETSU-R-97 simplified noise limit of 35 dB LA90 for 10 m height wind speeds of up to 10 m/s by a margin of 6.5 dB. A quiet bedroom typically has a noise level of 35 dB. This map shows the worst case (downwind) condition modelled noise results from the Environmental Appraisal, showing that all residential properties are outside the 30 dB level at a windspeed of 10 m/s.

References

[1] This figure is based on each kwH of wind energy production offsetting 0.430 kg of CO2 emissions from the current average UK energy mix BWEA Calculations page

[2] Calculated using the average UK power usage of 4.7 MWh per year.