Letter: Wind power is not delivering

Published on Wednesday 28 July 2010 11:16

I REFER to the article by Jenny Fyall (News, 25 July) "Windfarms only giving half power".

Windfarms are actually increasing carbon emissions. In a paper published on the website Master Resource, electrical engineer Kent Hawkins has shown that when wind power surpasses 5 per cent of power generated, the frequent ramping up and ramping down of the other base-load power sources (either fossil fuel or nuclear) to compensate for wind's unpredictable variability causes such inefficiency in power generation that overall carbon emissions rise.

Hawkins found this when studying power sources in the Netherlands, Colorado and Texas.

The energy company E.ON in its evidence to the Lords parliamentary committee noted that for every 1,000 MW of installed wind capacity another 900 MW of back-up capacity, fossil fuel or nuclear, is needed for times when the wind does not blow.

These back-up plants are run intermittently so they will increase carbon emissions.

Germany has about 20,000 turbines which has meant that five extra coal-fired plants have had to be built. Not one coal-fired electricity plant has been taken out of service as a result of building these wind turbines. Also wind turbines operate at efficiencies of about 25 per cent at best, so 1000MW of capacity will give only 250MW of electricity at best.

Dr Richard Dixon is wrong to associate 20 per cent of Danish electricity with wind power. In fact, about half of Denmark's electricity is produced at the wrong time, when it is not needed, and so has to be exported to other Nordic countries, at a loss to the Danish economy.

Terri Jackson, Bangor, Northern Ireland