The undesirable aspects of the Lewis wind farm have already been presented in great detail. However, is it not time to dwell in greater detail on the benefits of this scheme?
The whole purpose of wind generation is to reduce the emission of carbon dioxide, and it does this by replacing the electricity generated by fossil fuel and so shutting down or reducing the output from coal, gas or oil fired generating plant.
To replace the output from the nearest coal-fired power stations, the electricity generated in Lewis will have to travel down to the Firth of Forth and feed the consumers normally supplied by either Longannet or Cockenzie, and this is why the pylon line from Beauly to Denny is required.
The transmission losses over this distance could be as high as 15 per cent, with another 10 per cent possibly lost from Beauly to Ullapool, and another 10 per cent possibly lost in the undersea connector from Ullapool to Lewis.
The peak output of the Lewis windfarm is said to be 650MW, but with a load factor of just 33 per cent, the average output will be only 220MW. By the time it gets to Longannet only 140MW of this is left.
There is then the question of shutting down Longannet or Cockenzie to accommodate this meagre amount of electricity. But coal-fired power stations which are designed to provide steady undisturbed base load are notoriously difficult to turn down or turn up at will. So what will probably happen is that the generating turbines will be controlled to reduce power output by 140MW, but the boilers will still be left producing steam which will then have to be “spilled” instead of producing electricity. In this case the carbon emissions savings are zero.
Obviously, there are other ways in which the Lewis wind farm electricity can be managed so as to effect some small reductions in carbon emissions, but a figure of 600,000 tonnes per annum (your report, 6 February) is clearly absurd.
The only long-term benefit of the Lewis wind farm will come at the end of it’s 20-year lifetime, when, with the Beauly to Denny pylon line in place, the newly industrialised area of Barvas Moor will be the ideal site to place a 1000MW “clean energy” nuclear plant.
William Oxenham, Easter Currie Place, Currie, Midlothian
|Wind Watch relies entirely
on User Funding