Lynch Knoll Wind Turbine


The Lynch Knoll Wind Turbine (Nympsfield, Gloucestershire) was constructed in December 1996. It’s located on the road (Tinkley Lane) between Forest Green and Nympsfield.

There was a later application to put up another four turbines at this site but it was turned down by Stroud District Council in May 2001.

Lynch Knoll wind turbine

The following information is taken directly from a piece of literature that was given out during an open day.

Construction of the turbine took two days while the planning had taken four years. From memory the preparation of the site took more than two days as obviously the foundations had to be put in first.

The turbine is owned by Next Generation, and is the Enercon E40.

The operation of the turbine is completely automatic and computer controlled. The speed and direction of the wind are monitored by the instruments at the top of the turbine and the information is fed to the turbine controller at the base.

The controller then ensures that the turbine is turned to the correct direction, using the yaw motors, and that the turbine blades are pitched to the correct angle to maintain the optimum speed of rotation, using the blade pitch motors.

There are numerous fault sensors within the turbine, if a fault occurs the turbine will shut itself down, reset all systems and then restart automatically. If the turbine detects a serious fault and cannot restart it will ‘call’ the service engineers and provide details of the fault, via computer modem.

The turbine has no brake in the conventional sense. Stopping the turbine is achieved via an aerodynamic braking action.

The blades rotate or pitch to a position 90 degrees from the operational position and this has the effect of stopping the turbine within seconds. Each blade has its own pitch motor and battery back-up should the mains fail. Any one blade can stop the turbine rotating.

Wind Turbine Information

Start up wind speed 2.5m/s.

Cut out wind speed 25m/s.

Rotor speed 18 – 38 rpm.

Rated power 500KW.

Predicted plant availability 99%.

Annual output from this site 1,624,000 KWh.

Predicted hours of no wind 200 per annum.

Tower Material Concrete.

Tower Weight 100 tonnes.

Tower Height 42m.

Blades Material Glass fibre.

Blades Weight 0.75 tonnes.

Blades Length 20m.

Generator Weight 16 tonnes.

Concrete foundation 8x8x1m deep
150 tonnes

The annual output from this site, on average will produce 1,624,000 units of clean electricity.

That is enough to provide the complete annual requirements of 400 local homes. This is the equivalent to 4 villages the size of Nympsfield, 20% of the town of Nailsworth and 1% of the entire district of Stroud.

The electricity provided by this wind turbine is totally pollution free. This electricity displaces that from conventional sources and this provides significant reductions in pollution which are listed below

1398 tonnes of CO2
16 tonnes of SO2
5 tonnes of NOx

These gases contribute to Global Warming, Climate change and Acid rain.

Plus several tons of slag and ash, or Nuclear waste, and all pollution resulting from the mining, transport and processing of fossil fuels or Nuclear fuels.

Since the electricity from this site is used by local households and businesses there is a further saving of losses incurred in the National Grid when electricity is moved up and down the country. Wind power is locally produced and used.

All the energy used in the manufacture of this wind turbine and it’s transportation, site preparation and erection, will be replaced by the energy supplied here in the first 6 months of operation. The next 20-30 years will see a net benefit of up to 36 million units of electricity with NO pollution produced at all.