§ Mr. Rathboneasked the Secretary of State for Energy, pursuant to the reply to the hon. Member for Lewes of 3 July, what specific amount of energy would be saved by the introduction of double summer time during the summer and by the extension of summer time throughout the year.
§ Mr. John MooreIt has been estimated that double summer time during the period April-October would reduce electricity consumpion, mainly for lighting, by an amount equivalent to about 0.5 per cent. of total electricity usage in the period. I am advised that there would be little if any saving from extending summer time throughout the year, as the total number of units consumed in a typical 24-856W hour period in winter is substantially the same irrespective of the time system in operation. Demand for energy for space heating, water heating and power is unlikely to be affected by altering the clocks.
§ Mr. Rathboneasked the Secretary of State for Energy if he will identify and quantify the penalties of introducing double summer time in the summer and extending summer time throughout the year to which he referred in his answer to the hon. Member for Lewes on 3 July.
§ Mr. John MooreEnergy penalties could arise from an increase in other energy-using activities induced by an extra hour of daylight in summer evenings. These penalties cannot readily be quantified, but it is likely that they would largely offset the small saving in electricity consumption. For example, it has been calculated that if a consumer used only one extra gallon of petrol, this would be equivalent to the lighting he would save in 200 days. There would in addition be the social penalties, affecting particularly the more northerly parts of the British Isles, which led Parliament in 1970 to reject permanent adoption of British standard time.