Daylight savings all the time?

[Ken G]

Should we stay on daylight savings time all the time? Such a proposal has been bounced around here in Iowa. The idea is, in WWII, this in fact occurred, because it apparently does save energy. So why don't we do it at all times? The safety of kids on morning school buses doesn't seem to matter a lot if they are coming home in the dark instead. And the transition catches drivers by surprise and may actually cause accidents. Why not stay on it all the time? After all, noon doesn't come anywhere near the center of most people's day. Is there some reason we should prefer our darkness late in the day rather than early?

[Taks]

the problem is that all of those reasons are anecdotal at best, and actually proved wrong by all the places that don't ever go on DST (arizona, for example). IMO, we should stay on standard time always (which is now).

oh, and the energy thing is a farce as the energy savings are offset by the increase in air conditioning use. there is an economic factor, but some companies benefit and others lose. net gain is zero.

taks

[aurora]

Either we should have it all the time, or none of the time.

In the far north or far south (for example, in Canada or the northern US States, or in Argentina) daylight savings is stupid in the summer since it already is light until late in the evening without shifting the clock an hour.

Arizona and Hawaii have it correct, just don't bother.

[OptimusShr]

In the far north or far south (for example, in Canada or the northern US States, or in Argentina) daylight savings is stupid in the summer since it already is light until late in the evening without shifting the clock an hour.

Arizona and Hawaii have it correct, just don't bother.

Agreed. We have more daylight because of the rotation and tilt of the Earth and not by setting back clocks.

[Taks]

indiana does too, but they're switching over in 2006. that's only because of the trade issue with neighboring states, however.

taks

[hhEb09'1]

After all, noon doesn't come anywhere near the center of most people's day.

But it would be even farther off if we were on full time daylight saving time, right? Compared to standard time.

[swansont]

Agreed. We have more daylight because of the rotation and tilt of the Earth and not by setting back clocks.

It's more daylight when people tend to be awake. Without setting the clocks forward, the sun would be up at e.g. 5 AM and set at 7:30 PM where I live on July 21. I think most people stay up past 7:30, and only a small fraction of us are up and about by 6 AM.

[trinitree88]

In a lighter note....the local radio DJ suggested that everybody should turn their clocks ahead by 23 hours instead of back one.....that way you get one more day this year than everybody else! Now...what are you going to do with it? pete.

[Jens]

Should we stay on daylight savings time all the time? Such a proposal has been bounced around here in Iowa. The idea is, in WWII, this in fact occurred, because it apparently does save energy.

OK, I have a simple question about this. If we move the clocks ahead one hour permanently, won't people eventually adjust by changing their schedules back one hour? If suddenly we move the clocks ahead, people who are used to setting their alarm clocks at 7 will continue to do so. But eventually, young people may start getting up at 8 instead of 7. And then, companies will start to begin work at 10 instead of 9. And then you have people waking up at the same time as before the change.

If we really want to go back to a more natural pattern, how about shutting off the electricity grid at 9 o'clock every night?

[aurora]

Daylight savings time assumes that we are too stupid to adjust our schedules ourselves, and someone has to tell us when to get up and when to go to sleep.

If we just left it alone, people would set their own schedules, stores would open and close when it made the most sense.

In Hawaii, most stores close at 4 PM, because that makes the most sense for them.

[The Mangler]

4 PM? That seems a little early... Why does that make the most sense? Do people stop shopping after that?

[swansont]

4 PM? That seems a little early... Why does that make the most sense? Do people stop shopping after that?

Of course they do - the stores are all closed!

[swansont]

OK, I have a simple question about this. If we move the clocks ahead one hour permanently, won't people eventually adjust by changing their schedules back one hour? If suddenly we move the clocks ahead, people who are used to setting their alarm clocks at 7 will continue to do so. But eventually, young people may start getting up at 8 instead of 7. And then, companies will start to begin work at 10 instead of 9. And then you have people waking up at the same time as before the change.

This assumes a degree of organization that is unprecedented. To a large extent schedules are dictated by employers, so you'd have to have them all conspire to shift their schedules around, otherwise it would cost them money.

When the clocks spring forward, I could choose to sleep in and get up at the same solar time. But the traffic patterns I avoid by getting up earlier are going to foil me unless everyone else agrees to do the same thing. I don't see it happening.

[Wolverine]

The idea is, in WWII, this in fact occurred, because it apparently does save energy. So why don't we do it at all times?

The recent changes to DST passed by Congress adding two months worth beginning in 2007 not only repeated but relied upon these "energy saving" claims to effect their enactment.

From here:

The U.S. Department of Transportation (DoT), which has jurisdiction over DST, studied the results of the experiment. Based on consumption figures for 1974 and 1975, DoT reported that observing daylight time in March and April saved the equivalent of 100,000 barrels of oil each day, or approximately 1 percent of the nation's energy consumption.

I see the same figure claiming a saving of 100,000 barrels in the press as well, like here.

However... from here:

Based on consumption figures for 1974 and 1975, The Department of Transportation says observing Daylight Saving Time in March and April saved the equivalent in energy of 10,000 barrels of oil each day -- a total of 600,000 barrels in each of those two years.

I see the same figure claiming a saving of 10,000 barrels on other governmental pages, such as this one.

So which is it, 100,000, or 10,000? Not like an order of magnitude matters or anything.

Was satisfactory evidence ever compiled to substantiate the claim in either case? The source seems to be a DoT study performed during the energy crisis some thirty years ago, which doesn't appear to have been repeated.

Not trying to get political here whatsoever, mind you -- just looking for evidence regarding the above. They appear far-fetched to me.

[Ken G]

Exactly why we need our population to be better critical, and quantitative, thinkers! It's like they are thinking, 10,000 or 100,000, it's just another zero. Zero isn't anything, so it must be the same! A big number either way, right?

[Ken G]

Of course they do - the stores are all closed!

The only person still shopping is Yogi Berra...
(By the way, I can't verify this claim-- I lived on Oahu but don't remember the store hours being unusual. Then again, what's a store?)

[aurora]

4 PM? That seems a little early... Why does that make the most sense? Do people stop shopping after that?

In the smaller towns, yes. In the cities, of course, places are open later hours or 24 hours. But most people start work early in the morning, when it is cool, and then leave work early. Since the sun sets close to the same time year around, and since when it sets it is headed straight down, there isn't that long lingering twilight we get in higher latitudes.

So, they get their outdoor stuff done early.

they didn't need daylight savings time to tell them when to start work and when to leave work. They figured out what was best for themselves.

I think it also has to do with TV. In previous decades (before internet, before 100+ cable channels, yes there was a time before the internet!) people tended to set their schedules by the major TV networks ("prime time"). If true, that would explain why people in the eastern US tend to stay up "late" while people in the western US tend to go to bed "early".

I realize I am oversimplifying, but I think TV viewing habits in the '60s and '70s tended to drive some of the behaviour we still see.

[swansont]

In the smaller towns, yes. In the cities, of course, places are open later hours or 24 hours. But most people start work early in the morning, when it is cool, and then leave work early. Since the sun sets close to the same time year around, and since when it sets it is headed straight down, there isn't that long lingering twilight we get in higher latitudes.

So, they get their outdoor stuff done early.

they didn't need daylight savings time to tell them when to start work and when to leave work. They figured out what was best for themselves.

I think it also has to do with TV. In previous decades (before internet, before 100+ cable channels, yes there was a time before the internet!) people tended to set their schedules by the major TV networks ("prime time"). If true, that would explain why people in the eastern US tend to stay up "late" while people in the western US tend to go to bed "early".

I realize I am oversimplifying, but I think TV viewing habits in the '60s and '70s tended to drive some of the behaviour we still see.

Since, as you admit, the sunrise and sunset times don't vary much, I don't see how you can conclude what the people would do under different circumstances. At locations closer to the equator daylight saving isn't needed for this very reason. Do people in Arizona actually adjust their schedules, as your thesis predicts?

[aurora]

Since, as you admit, the sunrise and sunset times don't vary much, I don't see how you can conclude what the people would do under different circumstances. At locations closer to the equator daylight saving isn't needed for this very reason. Do people in Arizona actually adjust their schedules, as your thesis predicts?

Well, when I lived in southern Arizona, I had to bike 6 miles to the University. In the spring and fall, I would leave home before sunrise, and I would stay at the U until the sun started to go down. For obvious reasons.

In the winter, I would leave after sunrise (unless I had an early morning class), as even in Tucson it can get frosty overnight in the winter.

So I adjusted my schedule to the sun when I lived in Arizona.

I'm sure other people there do something similar.

[swansont]

Well, when I lived in southern Arizona, I had to bike 6 miles to the University. In the spring and fall, I would leave home before sunrise, and I would stay at the U until the sun started to go down. For obvious reasons.

In the winter, I would leave after sunrise (unless I had an early morning class), as even in Tucson it can get frosty overnight in the winter.

So I adjusted my schedule to the sun when I lived in Arizona.

I'm sure other people there do something similar.

But that's an adjustment to temperature. Did the university change its schedule to accommodate the changes in sunrise? That is how I interpreted your contention. e.g. 8 AM classes in winter, but 7 AM classes in summer, to utilize the extra daylight.

[aurora]

But that's an adjustment to temperature. Did the university change its schedule to accommodate the changes in sunrise? That is how I interpreted your contention. e.g. 8 AM classes in winter, but 7 AM classes in summer, to utilize the extra daylight.

No, apparently they needed the government to force them to change their schedules by an hour in order to save energy.

[swansont]

No, apparently they needed the government to force them to change their schedules by an hour in order to save energy.

But Arizona doesn't participate in daylight saving, and they don't set their own schedule according to the daylight hours. So your thesis would seem to be disproven.

[Wolverine]

No takers concerning my above post about claims of energy savings? I'm hoping to get some feedback.

[swansont]

No takers concerning my above post about claims of energy savings? I'm hoping to get some feedback.

According to this, 1 bbl of oil is equivalent to 1700 kW-hr

If, because of daylight saving, each of 100 million households spends that hour not requiring 340 W of lighting, etc., that's the same as 20,000 bbl of oil.

The 100,000 bbl number, if it wasn't a typo, obviously assumes more households and/or more energy savings per household. Perhaps the 10,000 number dates back to when the population was smaller - the US population is almost 50% larger than back in the oil crisis days, and I'm not sure how much improved energy efficiency and the general trend toward more devices/more use have cancelled. I think that the savings become less as you expand the start/stop times, because you turn on lights in the morning when you wouldn't have before.

[Wolverine]

If, because of daylight saving, each of 100 million households spends that hour not requiring 340 W of lighting, etc., that's the same as 20,000 bbl of oil.

That's why I'd like to see data -- I understand the rationale, but is it backed up by evidence? Seems to me it makes a number of assumptions resulting in claims I'd describe as tenuous at best.

[N C More]

Let's see, so I don't have to turn on my lights at 6:00 AM anymore, but I do have to turn on my lights at about 4:30 PM now. How is this saving me anything? The ratio of light to dark isn't really being influenced by either daylight savings time or standard time...that's due to the seasons and my geographic location. I honestly don't see how this saves energy?

[Gillianren]

Well, I, personally, get up around 10 or 11 AM. Granted, that means I pretty much never need lights in the morning, but that actually helps our case a little, because during June, I don't have to turn them on until about 10 PM. (Maybe closer to 9. But still pretty late.) Since, obviously, I'm a night person, I'm still up then. And even if I kept a more regular schedule, we get enough light here in the summer so that I wouldn't need to turn them on when I woke up with or without Daylight Savings, because it's light by 6 AM. Or at least, light enough so I don't feel the need to turn on lights. Heck, even in August, it's still bloody bright by 7, which is too early for me but when I get up at Ren Faire. (On account of the light blazing into the tent.)

[swansont]

Here is a pdf file from a California study (5.2 MB). I imagine the DOT would have similar reports, but I haven't done a thorough search.

[gopher65]

People use more energy during the day then they do at night. Therefore longer daylight ours = more energy useage. People also tend to use airconditioners more when it is light (even if the temperature is the same).

[Wolverine]

Here is a pdf file from a California study (5.2 MB). I imagine the DOT would have similar reports, but I haven't done a thorough search.

Thanks for that. As noted in the paper though:

Historically, it has been assumed that electricity can be saved with DST because people have an extra hour of daylight in the evening and thereby use less electric lighting. An overly simple approach to the energy-saving effects of DST is to look at the pattern of energy use before and after the existing spring and fall time changes. The shortcoming of this approach is that effects of DST are overshadowed by random weather and other causes. Averaging over a longer period lessens the random effects. The result of this process bears out the conventional wisdom that DST appears to save energy. However, the period of DST immediately following the spring time change has longer days that tend to be warmer. The lower electric use typically observed after the spring onset of DST may be purely the result of the warmer, longer days and not because of the time change. The same issue arises in the fall, but with energy use rising with the changeover to standard time while the days are getting colder and shorter.

I'm still skeptical based upon the number of assumptions made.