YOUR report claiming renewables have now overtaken nuclear as Scotland's main source of electricity ("Steps on road to cutting reliance on fossil fuels", The Herald, November 27) fails to differentiate between the concepts of energy and power.

While the total electrical energy produced by renewables did indeed exceed that from nuclear during the first half of 2014, the power delivered by renewables was intermittent.

Indeed for much of today the output from Hunterston B and Torness was 2175 MW, while the output from wind and hydro across the entire UK, let alone Scotland, was of the order of 1400 MW.

Colin R McInnes,

23 Williamwood Park West, Glasgow.