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REGION: North America
TOPIC: Government Programs
Online NewsHour
Originally Aired: March 9, 2007

Daylight Saving Time Arrives Earlier than Usual

Daylight saving time, which usually begins the first week of April, will be start earlier by four weeks starting this year, due to federal legislation passed in 2005. Two authors examine the impact of advancing the start of daylight saving time.
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JEFFREY BROWN: Two years ago, Congress added a little-noticed provision to an energy bill to move up daylight saving time by three weeks, to early March. The country was given time to get ready, and now, this Sunday morning, clocks will, or should, change.

Daylight saving time will also be extended a week in the fall. It's the first such move since 1986. The thinking: more sunshine means less power usage.

But in an increasingly automated society, that little time change is causing big headaches. A wide array of handheld electronic devices, like BlackBerries and cell phones, were set for the original time change and need reprogramming.

Companies are scrambling to update systems that control financial transactions, paycheck disbursals, power consumption, even meeting schedules. Apple and Microsoft have issued so-called "patches" that update systems for the change, and companies are working overtime to make sure the transition runs smoothly.

All told, the effort may end up costing business as much as $2 billion. The question now: How much will it benefit the nation as a whole?

Conserving energy

And we get some further explanation of all this from David Prerau, a computer scientist and author of the book "Seize the Daylight." He consulted with members of Congress when they drafted the 2005 energy legislation.

And Michael Downing, professor of English at Tufts University and author of the book "Spring Forward."

Mr. Prerau, the idea here is to save energy. Why don't you explain to us how that's supposed to work?

DAVID PRERAU, Author, "Seize the Daylight": Well, there's actually two different facets of it. One is that, by using more daylight in the evening, we can eliminate some electric light usage.

And everybody is up at sunset, but only some people are up at sunrise, and most businesses are closed at sunrise, but several are open at sunset, so you have more usage during the evening than the morning. So there's a net saving there, and most studies have shown a saving of electrical energy.

A second part of it is that daylight saving time smoothes the use of energy over the day -- electrical energy over the day -- so the energy can be generated more efficiently, because you use the least-efficient means at the peak energy usage. And by spreading that usage over the day, you're able to generate the same amount of energy more efficiently and less polluting.

Impact of daylight saving

JEFFREY BROWN: Now, Professor Downing, I was interested in reading about all this all today, that the idea of daylight saving goes back about 100 years, and for most of that time, there's been a debate about its actual impact. Tell us about that.

MICHAEL DOWNING, Tufts University: There's been a debate right from the start. In fact, it carries on right to today.

We tried this in World War I as a way of saving energy for the war effort, and Congress was told at that point that, no matter how hard we squeezed our clocks, we really couldn't come up with a lump of coal. And since then, Congress has repeatedly gone back to this well as a substitute for regular energy policy, like conservation.

The problem is, it's very hard, first of all, to document energy saving. But more importantly, there are a couple of unintended consequences with this law which has caused so much confusion.

One thing is, daily saving really does push us outside of our homes, and we go to the mall, and we go to the ballpark, possibly a social benefit. But when we go there, Americans we don't walk. We get to into our SUVs.

Since 1930, the petroleum industry has really known daylight saving actually increases the use of gasoline. And just this week, after 100 years of trying this as an experiment, the Department of Energy said that the jury is still out on whether we're going to save any energy with this program

Actual energy savings

JEFFREY BROWN: So, Mr. Prerau, how do you calculate the cost and benefits? Is it something worth trying at this point, or do you feel pretty confident that there are actual savings?

DAVID PRERAU: Well, historically, daylight saving time has always been used to save energy. And, in fact, there are 70 countries in the world that utilize daylight saving time, and almost all of them consider energy the main impetus why they use daylight saving time.

I should say that there was studies that have been done that have shown the saving in energy, and those studies did look into whether daylight saving time increased gasoline usage or travel or even effect on home heating oil. And they were found that there was no effect found at the time.

Of course, there's a new situation possibly, and so, as part of the law, Congress has asked the Department of Energy to make a new study of the effects of daylight saving time on energy.

JEFFREY BROWN: I notice, Professor Downing, you said that one clear winner here in the fall is the candy industry, right?

MICHAEL DOWNING: Absolutely. You know, daylight saving has been a remarkably effective spending plan in this country. The most persistent lobby since 1915 has been the Chamber of Commerce, initially on behalf of department stores, who realized that, if workers had sunlight in the evening, they'd stop and shop on the way home.

Since 1986, the last time we got an extra month of daylight saving, the candy makers have been pressing to have daylight saving include trick or treat. They figure, if our children have an extra hour of sunlight in the evening, they'll stay out longer, collect more candies, and it should mean millions of dollars in candy bars.

Daylight savings and technology

JEFFREY BROWN: Now, let's turn to the other part of this, which we mentioned in our setup, the technological side. Mr. Prerau, there have been, of course -- we all remember the Y2K scare. How do you compare this? What's going on, and how serious is it?

DAVID PRERAU: Well, there are some similarities, in that people had lots of time before Y2K, they knew it was coming, and a lot of people and companies waited for the last minute. And I think the same thing is true here.

Congress gave two years between the passage of the bill and the implementation of daylight saving time, and a lot of companies have waited for close to the end to do it.

However, I think the difference is that, for most computer applications and for most people, if a clock is off by an hour, it isn't a major thing. However, for certain things, such as calendaring systems and financial systems, based to a time stamp, that's very important, and they have to be updated.

And we will see. There could be some major glitches. But I think the main thing to think about is that this is a transitional problem. Once it's fixed, it's going to be fixed, and we may have this same daylight saving time period for a long time. The last time we changed daylight saving time, as we mentioned, was 1986, and we had that period of daylight saving time for 20 years.

JEFFREY BROWN: Well, Professor Downing, how do you see it? It is at least an interesting reminder of how we're all linked by computers and technology and kind of bound by them, I suppose?

MICHAEL DOWNING: Well, absolutely, linked is really the key word. You know, clocks have really limited virtues. You know, we could look up at the sun and tell the time, but what we rely on clock time for is synchronicity and predictability.

The United States Congress deciding to go it alone, to unilaterally change its period of daylight saving, is going to put us further out of sync with European clocks. It's been a big bust for the airlines who say it's going to cost them somewhere between $75 million and $150 millions -- are the latest estimates I saw -- just to renegotiate landing and takeoff times.

I just think, as a substitute for real energy policy, to create all this confusion, and the amount of work that has to go on in I.T. departments, whether you're in a hospital, a university, or a corporation, I don't see where the real win is going to be.

JEFFREY BROWN: All right. We'll all I guess wake up on Sunday morning and continue the debate there.

Michael Downing and David Prerau, thank you very much.



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