More Daylight Savings: Energy Boon or Scheduling Snafu?

Brian Handwerk
for National Geographic News
July 28, 2005
This week the U.S. Congress is expected to pass a mammoth new energy
bill that includes subsidies to oil and gas companies and encourages
nuclear power. Yet the bill's most controversial aspect may be its
monthlong extension of daylight saving time.

The move's energy-saving potential is uncertain. So few data exist on the subject that the plan calls for a new energy-impact study to be commissioned after the proposal becomes law—but before clock changes would actually take effect in 2007.

The bill calls for daylight savings to begin three weeks earlier, on the second Sunday in March, and to end on the first Sunday in November, one week later than daylight saving time currently does (see the history of daylight saving time in the U.S.).

Advocates such as Massachusetts Democrat Ed Markey, who is co-sponsoring the bill in the House of Representatives, say the plan is about more than just saving energy.

"In addition to the benefits of energy saving, less crime, fewer traffic fatalities, more recreation time and increased economic activity, day light saving just brings a smile to everybody's faces," Congressman Markey said in a press statement.

Some of the bill's boosters cite U.S. Department of Transportation studies from the 1970s. The studies evaluated the 1974 and 1975 extensions of daylight saving time. The 1970s extensions were designed to address the energy crisis spurred by an oil embargo.

In 2001 then-acting deputy assistant secretary for transportation policy Linda Lawson discussed the 1970s research before the House Science Committee. She reported that the studies had found an extension of daylight savings in springtime "might result in electricity savings of 1 percent in March and April, equivalent to roughly a hundred thousand barrels of oil daily over the two months." (See "How Long Will Cheap Oil Last?")

The study also noted reductions in crime and traffic accidents, attributed to extended daylight hours.

But Lawson also cautioned the committee about drawing conclusions from studies that were already old in 2001.

"I want to note that these studies are over 25 years old and were limited in scope," she told the committee. "Congress captured many of the benefits identified in our studies in the legislative changes to daylight saving time enacted in 1986. There have been dramatic changes in lifestyle and commerce since we completed our studies that raise serious questions about extrapolating conclusions from our studies into today's world."

Energy-Savings Evidence in Short Supply

Recent research on the subject is thin on the ground. The state of California's energy commission, however, studied the effects of daylight saving time on energy costs during California's 2001 energy crisis.

"Our report indicated that if we [extended] daylight saving time through all of March, there would be a decline of electricity use at peak hours of about 3.5 percent," said Claudia Chandler, the organization's assistant executive director.

"However, overall electricity use would only decline about one half of a percent. You're basically shifting noncritical energy use to later in the day," Chandler said. "It was assumed that people would stay outside later and that when they came in they would go to bed earlier because it got dark."

"In California it's all about shifting use to off-peak hours after 7 p.m.," Chandler continued. "I don't know how it might work in states that don't have the same kind of weather-driven [usage] peaks as California."

The plan's opponents point to potential problems that have little to do with regional weather patterns.

Scheduling Snafus?

The airline industry is adamantly against a change of the daylight saving calendar, which officials say will severely affect scheduling.

"There will be disruption all over the place. If [daylight saving time] is extended [by] four weeks, we'll end up with some really major difficulties," Anthony Concil said. Concil is spokesperson for the International Air Transport Association, which represents 265 airlines that account for 94 percent of all international scheduled air traffic.

"When Europe and the U.S. are on different times, connections become less convenient. Right now there is one week of discord between the U.S. and Europe so it's sort of at a manageable level," Concil said.

If the energy bill passes in its present form, every year "you might have a monthlong period where you have lousy connections, so from a traveler's perspective it's not going to be particularly good," he added.

Airlines may ultimately feel the change where it hurts the most—on the bottom line.

"It's going to be expensive for airlines," Concil added from the IATA's Geneva headquarters. "Particularly for U.S. carriers—and they are in a difficult climate right now—it's a major issue, as well as for carriers traveling to and from the U.S."

The so-called 80/20 slot rule at airports is a significant problem. It means that a plane must be present in an airline's assigned slot for 80 percent of the time allotted to the airline. The time shift could leave slots open at crowded airports, and the slots could be taken away from airlines as a result—use 'em or lose 'em, in other words.

In addition, computer groups are raising fears that the extension could cause wide-scale scheduling snafus.

The nonprofit Calendaring and Scheduling Consortium, which includes leading universities, software giants like Oracle, and even NASA's Jet Propulsion Laboratory, has prepared an advisory document for Congress. The statement warns that the current bill does not allow for enough time to prepare the United States' computer-based scheduling systems.

"It's not a matter of whether the proposal is right or wrong. It's a matter of practicality," the advisory says. "We suggest a simple delay of the effective date to [ensure] that the calendar and scheduling vendors and consumers have ample time to prepare for any changes."

Running the gamut from science to faith, religious observances and calendars tied to sunrise and sunset times would also be affected. Several Jewish groups have lodged formal complaints. They say that a later sunrise during the extension periods would hinder observant Jews' ability to pray at sunup and still make it to work by 9 a.m.

The Chicago-based National PTA and other education groups have raised child-safety concerns.

"National PTA is pleased that the U.S. House and Senate conferees scaled back the original proposal for extension of daylight-saving time in the winter months," a PTA press statement says. "We remain concerned about the potential safety issues the extension into March may cause due to the increased danger of traveling to school in dark hours."

The PTA urges a congressional study on student safety, in addition to the proposed energy-conservation study that is already part of the proposal.

From safety to saving energy, it appears that the true impact of extended daylight saving time may not be understood until after the energy bill becomes law.

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