Glass Moor Wind Farm
The Glass Moor Wind Farm was a development by Wind Prospect Developments and comprises of eight turbines located on land at Glass Moor, Pondersbridge, Cambridgeshire.
Construction of the wind farm commenced in May 2005 under a Turnkey Contract between Repower UK, and Siif Energies, part of the EDF Group. Repower UK and their sub contractors continue to construct the wind farm wih the erection of the turbines on the 24th November and expected to be complete before the end of the year.
Repower are to use the MM82, the same turbine installed at Long Hill Road, March with an overall tip height of 100m
Different Types of Turbine
Wind turbines may be designed in different ways and many of the differences have come about from a desire to minimise noise emissions:
Upwind & Downwind Machines
The majority of horizontal axis turbines are designed in such a way that the blades are always upwind
of the tower. This has the effect of minimising any airflow changes as the blades pass the tower. Some turbine designs, particularly some of those installed in the USA, have the turbine blades downwind of the tower. With this type of design, a strong pulse can sometimes be heard with each passing of a blade behind the tower. However, most turbines currently operating in the UK are of the upwind design.
Twin Speed and Variable Speed Machines
Most horizontal axis turbines rotate at a constant speed, usually between 25 and 50 rpm, irrespective of wind speed. However, twin speed machines operate at a reduced speed when the wind is light. This produces less noise and means that when the noise of wind in the trees is low, the noise
of the turbine is also significantly lower by up to 10 dB(A). Variable speed machines change speed continuously in response to changes in wind speed and, although noise output may be higher at higher wind speeds, it is lower at low wind speeds where the low background levels occur.
Direct Drive Machines
Direct drive turbines are the latest design concept in turbine technology. Simply put, these machines have no gearbox or drive train, and consequently no high speed mechanical (or electrical) components. Direct drive turbines are therefore much quieter than gearbox machines as they do not produce mechanical or tonal noise. An example of this type of turbine is the 1.5MW 'Ecotricity' turbine installed at Swaffham in Norfolk in September 1999.