Early Daylight Savings Equals Energy Savings of .05%

| Fri Mar. 9, 2007 6:00 PM EST

Early daylight savings time starts on Sunday, three weeks early, as dictated by Bush's 2005 Energy Policy Act. However, even as airlines and businesses struggle to adjust their computer and scheduling systems to accommodate the time change, turns out there's precious little evidence that the extra hour of daylight will save any significant amount of energy.

A study by the California Energy Commission, released last month, found that if people maintain their daily schedules then spring and fall daylight savings time extension would probably cause a 2 to 5% drop in the evening while morning electricity use would grow some, but probably not enough to offset evening savings. "The net effect is small and uncertain: a best guess of total net energy savings is on the order of ½ of 1%, but savings could just as well be zero."

In fact, the researchers go on to say there's a 25% chance that the early time change will actually increase electricity use, and that they're 95% confident that the energy savings range from a potential increase of 1.1% to a potential decrease of 2.2%.

Part of the reason for the low energy savings may be because of an increase early morning electricity use. Sunrise will move from about 6:15 a.m. to 7:15 a.m., meaning students and early-morning workers may need to use more lights while getting ready. Schools and coffee shops and other places that open in the early morning will also need more electric lights to function. As an example of how early daylight savings time can backfire, take the case of Australia: they instituted an early daylight savings time for the 2000 Olympics, and saw an immediate spike in early morning electricity use, resulting in an overall energy increase and higher electricity bills.

--Jen Phillips

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