Study: Daylight saving time a waste of energy

…while the lighting costs were reduced in the afternoons by daylight saving, the greater heating costs in the mornings, and more use of air-conditioners on hot afternoons more than offset these savings. Kotchen said the results were more “clear and unambiguous” than results in any other paper he had presented.

Daylight saving was initially introduced, and has been extended, because it was believed to save energy, but the studies upon which this idea was based were conducted in the 1970s. A big difference between then and the present is the massive increase in the take-up of air conditioning. In hot periods daylight saving time means air conditioners tend to be run more when people arrive home from work, while in cooler periods more heating is used.