"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.
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 moston the bottom line.
"It's going to be expensive for airlines," Concil added from the IATA's Geneva headquarters. "Particularly for U.S. carriersand they are in a difficult climate right nowit'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 resultuse '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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