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The energy behind daylight saving time

While daylight saving time (which starts Sunday at 2 a.m.) is popular as an extension of light so that summer days may be more fully enjoyed, the rite of adjusting clocks in spring and fall was mostly influenced by energy savings.

While daylight saving time (which starts Sunday at 2 a.m.) is popular as an extension of light so that summer days may be more fully enjoyed, the rite of adjusting clocks in spring and fall was mostly influenced by energy savings. And candy consumption.

Yes, DST is earlier than it once was. Until 2006, the springtime start was the first Sunday in April, but that was moved to the second Sunday in March with the Energy Act of 2005 as a way to conserve energy mostly by reducing evening home lighting. However, there are conflicting studies on whether any energy is really saved.    

And the switchback to standard time is a week later in the fall, owing to Halloween. Candymakers and child-safety advocates successfully lobbied Congress to push the date to the first Sunday in November to allow an extra hour of sunlight for trick-or-treaters.

But the annual clock switch will have complications. Europe adjusts clocks on the last Sunday in March and again the last Sunday in October, causing some confusion on each end. In the continental United States, Arizona is alone in observing standard time year around — except that the Navajo Nation that is located in Arizona and two other states observes DST.

DST is also not observed in Hawaii, American Samoa, Guam, Puerto Rico and the Virgin Islands.

For sake of grammatical purity, please know that it is Daylight saving time — no “s” on saving. But, in truth, there is no saving of daylight, either. That’s why the Europeans call it “summer time.”

And while the annual movement of time may seem to be generally popular, there are pockets of those who plain don’t like it. Those who benefit are outdoor enthusiasts like golfers and boaters who like the extra play time in the warmth of summer. But those with sleep disorders or whose work is tied to the sun (especially farmers) tend to dislike DST. In addition, those in broadcasting say it wreaks havoc with “prime time” revenues.

Divided cities
DST has been controversial at times: in the Twin Cities there was the standoff in 1965 between Minneapolis (which stayed with standard time) and St. Paul (DST). The next year, President Lyndon Johnson signed the Uniform Time Act that established DST across all time zones, except that state legislatures could opt out. Newspapers back then often published letters to the editor by those advocating for “God’s time” over the “unnatural” DST.

In truth, it wasn’t God so much as the coming of the railroads that established the modern method of uniform time along with 24 worldwide time zones. Up to then, time was a local matter with noon set to when the sun was its highest overhead point — “high noon.” Clocks at a prominent place in town — usually a church steeple or a jewelers shop — became the local time authority. 

But the railroads needed more uniform time to keep schedules for east-west trackage. It was in 1840 that the England’s Great Western Railway adopted “London Time” that eventually won out over stubborn local resistance. In 1880 England uniformly followed Greenwich Mean Time, which today remains the authority for worldwide time.

In North America, railroads in the United States and Canada adopted a uniform time in 1883. Because of long east-west tracks the railroads also divided the continent into the time zones that were adopted into law with the Standard Time Act of 1916. The original zones are still in use today, although there have been attempts to make some modifications. 

Well into the 1970s, North Dakota and South Dakota fought changing the division line between Central and Mountain time to align with state boundaries rather than the Missouri River.  Tradition won out, and the result in North Dakota is that Bismarck is on Central time and Mandan just across the river is on Mountain time.

War time

In 1918, President Woodrow Wilson instituted a “time to preserve daylight” during WWI, and that remained in effect until 1919 when Congress overrode Wilson’s veto of the first national attempt at what is now DST. President Franklin D. Roosevelt instituted year-around “War Time” in 1945 and the one-hour national adjustment remained in some form until 1966 when Johnson signed the Standard Time Act.

But the concept for “saving daylight” is credited to Benjamin Franklin, who was living in France in 1784 and whimsically wrote that Parisians could save on candles by adjusting their clocks in summer. Franklin wrote:

“…183 nights between 20 March and 20 September times 7 hours per night of candle usage equals 1,281 hours for a half year of candle usage. Multiplying by 100,000 families gives 128,100,000 hours by candlelight. Each candle requires half a pound of tallow and wax, thus a total of 64,050,000 pounds. At a price of thirty sols per pounds of tallow and wax (two hundred sols make one livre tournois), the total sum comes to 96,075,000 livre tournois.”

His plan wasn’t adopted.