Two years ago, when Congress passed a law to extend daylight saving time by a month, the move seemed a harmless step that would let the nation burn a little less fossil fuel and enjoy a bit more sunshine.
Representative Fred Upton, a Michigan Republican, predicted that children would rejoice at the prospect of an extra hour of daylight trick-or-treating on Halloween. But there is no rejoicing among corporate technology managers.
The change takes effect Sunday, as daylight saving time begins three weeks earlier (and ends a week later, on the first Sunday in November). And many companies are scrambling to reset BlackBerry e-mail devices, desktop PCs and big data-center computers used to automate payrolls, purchasing and manufacturing.
This puts the United States out of sync with the rest of the world for longer than usual this spring, almost certainly disrupting not only computers but also the business and travel schedules of companies, workers and travelers. Most of Europe goes to daylight saving time March 25, two weeks after America, while most of Asia, Africa and South America do not observe daylight saving time at all.
Any device that has an internal clock looms as a potential problem and must be tweaked for the time change, usually with a software patch. Most internal clocks in computing devices are programmed for the old daylight-time calendar, which Congress set in 1986.
“It’s a massive amount of work to get everything in order,” said Kim Stevenson, a vice president at Electronic Data Systems, a large technology services company. “And the do-nothing plan is a high-risk plan.”
The daylight-time shift, according to technology executives and analysts, amounts to a “mini-Y2K.” That is a reference to the rush in the late 1990s to change old software, which was unable to recognize dates in the new millennium, 2000 and beyond.
The fear was that computers would go haywire, and there were warnings of planes falling from the skies and electronic commerce grinding to a halt. Billions of dollars were invested to fix the so-called millennium bug, and there was no wave of computer-related disasters.
This time, with extended daylight saving time, the problem is subtler. The potential pitfall is a disruption of business, if the clocks inside all kinds of hardware and software systems do not sync up as they are programmed to do. In a business world that is increasingly computerized and networked, there could be effects on everything from programmed stock trading to just-in-time manufacturing to meeting schedules.
National hotel chains, one technology consultant said, have often automated their wake-up call services in one or two data centers. Having wake-up calls made an hour late for a couple of weeks, he noted, would certainly tarnish a hotel’s reputation for customer service.
For consumers, the greatest potential impact will be on e-mail and calendar programs like Microsoft Outlook, used to schedule dentist visits, soccer practices, evening entertainment and other appointments.
The latest Windows operating system, Vista, is not affected, and for those running Windows XP Service Pack 2, online software updates have been pushed out automatically to correct the problem. Microsoft and Apple are also making software patches and instructions available on their Web sites.
“This is mainly an annoyance for consumers, but it’s a major headache for corporate technology departments,” said Jeffrey Hammond, an analyst at Forrester Research.
For the roughly 7,000 public companies in the United States, Mr. Hammond estimates the total cost of making computer fixes to deal with the daylight saving time shift at more than $350 million. “It’s causing a lot of corporate technology people sleepless nights,” he said.
The impact extends beyond computers themselves. For example, utilities have begun deploying sophisticated time-of-use meters that measure electricity consumption, often at 15- or 30-minute intervals. They charge different rates at different times of day — mainly for large commercial customers — as part of the utilities’ programs to manage peak loads on their grids.
Those meters have to be reprogrammed for the daylight saving time shift, sending technicians out for on-site visits costing $40 to $200 each, according to Rick Nicholson, an analyst at the IDC research firm.
The energy savings from extending daylight time are not great, but could mount, according to studies. A report last year by the Energy Department projected savings in electricity at four-tenths of a percent each day of extended daylight savings time — or three one-hundredths of a percent of annual electricity use. Daylight saving time modestly reduces evening electricity use.
Still, tiny savings each year could add up in the long run. The American Council for an Energy-Efficient Economy, a nonprofit group, estimates that the cumulative benefit through 2020 of longer daylight saving time would be a saving of $4.4 billion and 10.8 million metric tons less carbon spewed into the air.
The 2005 energy bill gives Congress the option of repealing the daylight saving time extension, if energy savings are not achieved.
But there is no turning back for the technology sector. The major software suppliers are offering patches and assistance to customers. The largest software company, Microsoft, has a Web site to help corporate customers and consumers, the Daylight Saving Time Help and Support Center, at microsoft.com/dst2007.
“This is a challenge for the whole industry,” said Rich Kaplan, vice president for customer service at Microsoft. “But for most users, this is mainly a nuisance issue. It’s not as if you’re going to lose any data — your documents, e-mail, digital music or pictures.”
Gregor S. Bailar, chief information officer at Capital One, a large bank and credit card company, has led a lengthy program to get all its data centers and PCs ready for the daylight saving time shift.
For most people in business, Mr. Bailar said, the main problem is going to be synching calendars and meeting schedules. “My advice to the common Luddite is to confirm, confirm and reconfirm your appointments in March and April,” he said.
Or perhaps not. Mr. Bailar suggested another option: “What better excuse to miss that boring budget meeting, at least for a month?”