Daylight Saving Wastes Energy

A new study show that daylight savings time result in higher energy use, reports the Wall Street Journal, examing the effect of Indiana’s recent move to DST.

Daylight Savings Time has always baffled me – I never understood why we have it, and why we switch back – so I made myself a few Excel charts to understand it better. Essentially, with the typical 9-5 workday (and proto-typical sleeping hours) daylight savings time results in more hours of sunlight in the evenings (i.e. after work), during “awake time”, especially in the summer. The argument is that this will save on lighting costs. But during the winter, daylight savings time would result in more darkness during morning “awake time,” so we switch back.

The study indicates that the savings in lighting in the evening is offset by the higher cost of air conditioning – i.e. when there is more sunlight, homes are hotter in the evenings, so people run their air conditioners more than they otherwise would.

This is the best argument against daylight savings time I have heard since Ohio University students rioted over the loss of an hour of drinking time.