asked the Secretary of State for Energy what is his Department's estimate of the saving in energy from the ban on daylight advertisement illumination; and what would be the saving from a ban on similar advertisements at night.

The precise energy saving resulting from the ban on daylight advertising illumination is not known but by itself will not be large. The annual savings from a total ban on similar advertisements at night might amount to perhaps ½ million tons of oil or oil equivalent, assuming average annual generating efficiency.