Will the Daylight Savings Shift Do Us Any Good?

March 9, 2007 — -- Next week, by congressional mandate, you will probably stumble out of bed an hour early -- possibly, depending on your schedule, before dawn.

It's all in the name of saving energy. At least, that's what we were told.

Congress made daylight-saving time three weeks earlier this year. Proponents argued that the shift would reduce America's energy consumption during that period about 1 percent.

Will it work? Not very likely, say two young economists at the University of California at Berkeley.

Congress's logic was simple. If there's an extra hour of sunlight in the evening, people will turn on fewer lights. The Transportation Department once did a study saying daylight savings reduced America's use of oil by 100,000 barrels a day.

But Ryan Kellogg and Hendrik Wolff, who are working on their doctorates in economics, say the reduced need for light in the evening will likely be negated by the increased need in the early morning.

The folks in Washington apparently hadn't considered this. The daylight savings shift was a three-paragraph item in a 550-page energy bill in 2005. And that study from the Transportation Department? It's more than 30 years old.

Kellogg and Wolff came to their conclusion by studying Australia, where several states extended daylight-saving time (DST for short) by two months in 2000 to accommodate the Olympic Games in Sydney that year.

They compared electric demand in the state of Victoria, which extended DST, with its next-door neighbor, South Australia, which did not.

"Our results show that the extension failed to conserve electricity," they wrote.

"If it's dark enough in the morning that pretty much everyone has to turn on the lights," said co-author Kellogg, "what that means is that that increase in morning electricity consumption is going to be so big that it offsets any benefits we get from the extra light in the evening."

In fact, the two said, shifting Australians' clocks led to a tiny increase in power use.

"The response I've been getting when talking to people is, 'Well, why are we doing this if this doesn't save any energy?'" said Kellogg.

Australia, of course, is not America, but the two researchers say their study is not a good sign. "While we cannot directly apply our results to other countries without adjustment for behavioral and climatic differences, this study raises concern that the U.S. is unlikely to see the anticipated energy conservation benefits from extending DST."