Daylight saving time came into being as a tool for actual savings: A later sunset meant people might use less candle wax, or coal, or lamp oil.
But does daylight time deliver any real savings to the average consumer in 2023 America?
Decades of research haven’t yielded a definitive answer. However, some top time-shift scholars now believe daylight time costs us in the end.
“I know of no credible study that has documented any savings whatsoever in energy from adopting daylight saving time,” said William Shughart, an economist at Utah State University. “As far as I can tell, all of the effects of daylight saving time are costs.”
That finding may come as a shock, at least to history buffs.
Ben Franklin seems to have seeded the idea of daylight saving in 1784, with an essay that suggested Parisians might save money on candles if they shifted their schedules to rise with the sun.
Germany introduced daylight time in 1916 as a wartime measure, theoretically to save energy by moving sunset later in the day. More sun meant less artificial light. America briefly adopted daylight time in 1918. The time shift resumed in World War II.
America experimented with permanent daylight saving time in the Nixon era
America adopted its modern schedule of pivoting between daylight time and standard time in 1966.
The nation experimented with permanent daylight time amid the 1974 energy crisis. After a winter of dark mornings, public support eroded, and the experiment ended.
Congress and the Nixon administration thought permanent daylight time would reduce the nation’s consumption of oil until the crisis abated.
“But it was just a wild idea that had no empirical support,” Shughart said. “It sounds plausible, but there’s nothing there.”
The last big time-shift change came in 2007. The nation moved the start of daylight saving from the first Sunday in April to the second Sunday in March and delayed its end from the last Sunday in October to the first Sunday in November.
This fall, the great resetting comes on Nov. 5.
In 2008, the Energy Department attempted to measure the actual savings in daylight time. In a report to Congress, researchers announced that the nation had reduced its energy consumption by an annual rate of 0.03%. The meager savings came in reduced electricity consumption in the evenings during the extra days of daylight time.
Other research, however, has suggested the reverse: The semiannual time shift exacts a cost, and daylight time nets little or no savings.
A landmark study, initially published in 2008, found that the switch to daylight time cost the citizens of Indiana $9 million a year, or $3.29 per household, in higher electricity bills. The study took advantage of a natural experiment: Much of Indiana adopted daylight time in 2006.
Matthew Kotchen, a Yale economist, co-authored the paper while employed by the University of California, Santa Barbara.
Daylight saving may have reaped more actual savings in the old days
He theorizes that daylight time may have yielded savings to energy consumers decades ago when a larger share of energy consumption went toward lighting homes.
Today, lighting costs seem negligible next to the monthly expense of heating and air conditioning. And that’s where daylight time can exact a cost.
“Shifting to daylight saving makes you wake up at the coldest, darkest part of the day,” Kotchen said.
Imagine your daily schedule in the final days of daylight time, compared to the first days of standard time. You wake up an hour earlier. Your house is colder and darker at 7 a.m. than at 8 a.m. Upon awakening, you may raise the temperature on your thermostat to heat your home.
After the time change, you awaken and fire up the furnace an hour later. The sun hangs higher in the sky, your home warmed by its rays.
Daylight time tends to cost the most in the autumn, Kotchen said.
The Indiana study focused on a cool, northern state. In the South, by contrast, Americans might spend more on energy at the end of the day during daylight time, returning from work or school to a home that is a bit warmer.
“It’s sunny and hot. You crank up the AC,” Shughart said.
Many other studies have attempted to measure whether daylight time saves energy and, thus, money. One 2017 meta-analysis reviewed dozens of papers and found that, on average, daylight time costs 0.34% less in electricity consumption.
Other studies have found that the twice-a-year ritual of resetting clocks has a cost of its own.
Researchers have tracked an increase in heart attacks and workplace accidents and a dip in productivity after the spring shift, which robs the nation of an hour of sleep.
One oft-cited 2016 analysis, from the Virginia firm Chmura Economics & Analytics, calculated that the time change cost the national economy $434 million.
“I think the major downside of daylight saving time is physiological,” Shughart said. “It shocks your body twice a year, and it almost doesn’t matter which way the time is shifting.”
Shughart earned plaudits for a back-of-the-envelope calculation that the very act of resetting clocks cost the nation $1.7 billion a year.
That figure represents lost productivity when all of us pause for 10 minutes in spring, and another 10 minutes in fall, to adjust our timepieces.
Shughart concedes that the societal cost of clock-setting is smaller today than in 2008 when he published his figures because so many of our gadgets now change the time on their own.
Most of us want to stop changing clocks, but we can’t agree on how
Much of the nation has coalesced around the notion that we need to stop resetting our clocks.
In recent years, 19 states have passed laws or resolutions to make daylight saving permanent if Congress allows, some of them contingent on the actions of other states. Federal law does not now permit permanent daylight time.
Two states, Arizona and Hawaii, observe permanent standard time, which the law does allow.
While legislation seems to favor daylight time, many Americans and state lawmakers simply want to abolish the clock changes.
More:Why do we ‘fall back’ for daylight saving time? What to know about the time change
The added cost of daylight time, if such a cost exists, has not loomed large in the debate.
“Aggregated across an entire population, the energy savings or costs are pretty marginal,” said Jeff Bridges, a Democrat in the Colorado Senate who co-sponsored legislation that will make daylight saving permanent if federal law permits.
“Personally, I don’t care which way we go,” he said in an email. “I just want the madness of clock-changing to end.”