asked the Secretary of State for Energy how much electricity is produced or saved in a full year if £1,000 million is invested in (a) a new nuclear power station of the kind to be built at Torness or Heysham, (b) a new coal-fired power station similar to Drax B, (c) a new oil-fired power station similar to the Isle of Grain and (d) energy conservation measures using existing technology to economise in the final use of electricity.

Investment decisions on generating plant are taken in the light of total lifetime costs and benefits and no meaningful comparison can be related solely to initial capital investment or to a particular year. Similar considerations apply to the appraisal of opportunities for investment in energy conservation, which are not normally specific to electricity, and whose costs and benefits vary. Meeting longer term United Kingdom energy needs will require substantial investment both in the energy industries and in energy conservation.