Daylight Saving Time: Fall Back, But Why?

Sunday at 2 a.m. we set our clocks back an hour, "falling back" to Standard Time. Do you ever wonder why most of the United States moves its clocks back and forth every year? Call me old-fashioned, but I think that using the position of the Earth around the sun was a good enough system.

The first reason that comes to my mind is that DST saves on energy, and in turn, saves us money. One of the strongest arguments since before DST was implemented was that moving clocks forward in the springtime would give us a little extra time at night before turning on the lights – or lighting candles – to save on electricity -- or wax.

Back in the 1780s, Benjamin Franklin suggested, in an anonymous, tongue-in-cheek letter to the Journal of Paris, that the city could save nearly one billion livres tournois just by "using sunshine instead of candles."

"An immense sum! That the city of Paris might save every year," he wrote. (Anyone know what a livres turnois would be worth today?)

And later, during the first and second World Wars, U.S. officials suggested DST as a way to conserve fuel for the war efforts. In the mid-1960s, with lots of lobbying from the transportation industry (read: railroads) the Uniform Time Act was passed. States were asked to make a decision about DST so that train schedules could be more easily regulated.

More than 200 years after Franklin's snarky editorial (which suggested Parisians be taxed on widow shutters that keep the sunlight out), in 2005 President Bush signed the Energy Policy Act which called for extending DST by a month.

And what about the farmers? I have also heard that for some reason, farmers were one of the strongest supporters of DST, though I was never really sure why. Something about having more hours of daylight for farming, maybe.

Not so, according to Michael Downing.

In fact, he writes in his book "Spring Forward: The Annual Madness of Daylight Saving Time," farmers were against DST from the start. Apparently, the folks who actually lobbied for the change to DST (politicians and business people) didn't know much about farming and put forth a host of "benefits" that the actual farmers found laughable.

For instance: in a pro-DST pamphlet called "An Hour of Light for an Hour of Night," the authors wrote that "most farm products are better when gathered with dew on," and with DST implemented, farmers will wake earlier, picking delicious, dew-soaked fruits and veggies.

But many farmers disagreed, saying it was much more difficult to pick wet crops, not to mention that now, the already early-rising farmers had to wait an extra hour for the sun, so that they could even see what they were doing.

"Beyond their interest in the league of nations, beyond everything else, except bringing the boys home from France, they wanted the daylight-saving law repealed," said a Kansas congressman in 1919. According to Downing, the congressman was holding bundles of letters from farmers as he addressed the House hearings on the repeal of DST. 

So ... back to energy savings. What exactly is it that we're saving?

A 2007 study prepared for the California Energy Commission came to the conclusion that, not only is it unclear that Daylight Saving creates a significant energy savings, but that there is a one in four chance that DST actually leads to a small increase in energy use.

The National Bureau of Standards goes further, reporting that DST creates no significant energy savings (or differences in traffic fatalities due to darkness, as proponents of DST sometimes claim).

On the other hand, a 2008 study by the U.S. Department of Energy reported that Bush's four-week extension saved about .5 percent of energy usage across the nation per day, which equals about 1.3 trillion watt-hours.

Even different branches of the same federal government can't seem to come to an agreement.

Research has also suggested that the more than one and a half billion people who live in places that implement DST may be negatively affected physiologically by the change.

"This seemingly small hour translates to a repeat of 10 weeks in the annual progression of the relationship between our sleep-wake cycle and dawn," said researcher Till Rosenberg.

"Four weeks in spring and six weeks in autumn. In effect, it's as if the entire population of Germany, for example, is transported to Morocco in spring and back again in autumn.

"After taking seasonal adjustment into account, our results show that the human circadian clock does not adjust to the DST transition."

So, why do we Fall back? Who knows, but try to enjoy the "extra" hour.