Indiana had long been a hold-out on the switch to Daylight Savings Time (DST), an issue which bothered some of Indiana’s residents. They were tired of not being on the same time as their neighbors in other states. Some counties opted to adopt DST before the state legislature considered it, thus providing a chance for the local electricity provider, Duke Energy, to perform a study.
The result? Here’s the direct quote from a Wall Street Journal article:
Having the entire state switch to daylight-saving time each year, rather than stay on standard time, costs Indiana households an additional $8.6 million in electricity bills. They conclude that the reduced cost of lighting in afternoons during daylight-saving time is more than offset by the higher air-conditioning costs on hot afternoons and increased heating costs on cool mornings.
There you go. Daylight Time, once thought to save electricity, doesn’t. The reason appears to be the proliferation of air conditioning and electric heat units in modern homes.
Unfortunately, those who still rely on studies from the 70’s refuse to accept these facts:
“One study of the situation in Indiana cannot accurately asses the impact of [daylight-saving time] changes across the nation, especially when it does not include more northern, colder regions,” (Rep. Edward J. Markey of Massachusetts) notes.
Mr. Markey, there are more states south of Indiana than there are north of Indiana. In regards to population, New York, Boston, and Pennsylvania are around the same latitude (i.e. roughly the same climate zone). Thus your argument only singles out the few states north of Indiana.
The bottom line is that when DST was first implemented during World War II, the main power consumption was for electric lighting. At that time it made sense to use sunlight as a primary lighting source for our homes. Since then, almost every single home has an air conditioning unit which uses a huge amount of power. Now throw in the recent use of compact fluorescent lighting, the lighting load will only continue to decrease. Implementing DST causes people who come home early to crank down their thermostats for cooling, or for those that wake up in the dark to crank up their thermostats. Thus, in my opinion, the energy argument for DST is no longer valid.