Visit Wales Now

Visit Wales and see some dramatic changes to the landscape

Excavation for the foundation of one wind turbine at Cefn Croes.

An unspoilt environment?

Besides being big, noisy and visibly intrusive, wind turbines have a lasting effect on the landscape. Building a wind farm is a major construction project and the land will never be the same again once the development is complete.

What is involved in building a wind power station?

 Access roads

The first step in building a wind farm is the access roads. These roads have to be wide enough and strong enough to transport the turbine component parts, the building equipment and the hoisting cranes into the site. The aggregate needed to build these roads is usually dug out from the sides of the surrounding hills from what is euphemistically referred to as ‘borrow pits’. In some instances, these roads are invading pristine wilderness and will open these areas up to vehicle traffic for the first time.

An access road at Cefn Croes.

Turbine foundations

Then the foundations are dug. Each modern turbine needs a reinforced-concrete foundation the size of an Olympic swimming pool. This requires about 1,000 tons of concrete. The concrete is either transported in along the access roads or a cement factory is set up at the site.

A turbine foundation and concrete plant at Cefn Croes. 

Note that a person is standing at the top left-hand corner of the foundation.

 What will happen to the concrete?

The concrete foundations and the concrete standing pads, needed for the cranes that erect the turbine towers, will remain in place forever. The developers are not expected to remove the concrete at the end of the wind farm’s operating life.

 Grid connections

A wind farm also needs a substation and miles of power lines and pylons to transport the electricity to the national grid. Wind farms are built far from the urban areas where the electricity is needed, so most wind-generated electricity is carried across great spans of open countryside.

A substation and pylons at Cefn Croes.

But don't wind turbines help reduce carbon dioxide (CO2) emissions ?

Unfortunately not. In spite of what the power generating companies and the wind farm developers say, wind turbines have very little effect on the total emission of CO2 from fossil fuel power stations.

The reason for this is simple. 

Energy output from wind varies from zero to 87% of their rated capacity, depending on the wind. If the wind speed is less than about 5 metres per second (11 mph), no electricity is generated; if the wind speed is greater than about 25 metres per second (56 mph), turbines are shut down for safety reasons. 

On average, wind turbines in the UK generate about 23% of their rated capacity.

All power plants need a certain amount of backup to cover down times, but wind power is unique in that the down times are intermittent and unpredictable. The backup for wind power must be running continuously, ready to go on stream immediately in response to changing weather conditions. The crucial point here is that this "spinning reserve" is burning fossil fuels and emitting CO2 even when not producing electricity.  

 To date it has been assumed as self evident that wind generated electricity will save carbon. There is very little evidence that this is the case and indeed mounting evidence that wind generated power is not carbon friendly. Current available figures bring us to conclude that during its lifetime one 3MW turbine will “save” 6,356 tonnes of carbon and “cost” somewhere between 27,213 and 40,773 tonnes of carbon. Dr. Sarah Myhill, of  Llangunllo, Powys, has studied the problem. Click here to download her  research paper.

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