Ms Valerie Freeman:

Yes. We believe that wind power and CO₂ savings need to be assessed in a proper cost benefit analysis. We are not just talking about a monetary cost.

Sir Donald Millar, the former chairman of Scottish Power, spoke about the economics of wind power to the UK climate change committee. He was coming from an engineering perspective but knows the energy sector. He said:

The assumption that each MWh of electricity generated from wind saves the equivalent in CO₂ emissions from fossil fuel power stations would not be supported by any engineer with experience of operating power plant. The considerably lower efficiency of the back up thermal plant running at part loads, together with the additional losses from frequent deloading and reloading as the wind strength varies, all consume additional fuel. The jury is still out on the exact implications of this but there is accumulating evidence from an analysis of actual system operations both in the USA and more recently for the Irish Grid that high wind penetrations save little or negligible emissions of CO₂ and can in some circumstances actually lead to increases.