Time to Fall Back From Daylight Savings Time

The change does not save energy, William F. Shughart II writes.

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Almost everyone in America will suffer from jet lag during election week—and they won't even have to be in travel mode. Except for those fortunate enough to live in Arizona and Hawaii, the hour of daylight "saved" on Sunday, March 9, will be withdrawn at 2:00 a.m. Sunday, Nov. 2, as clocks revert to standard time for the next four months.

Since it was first introduced during World War I and then regularized by the Uniform Time Act of 1966, Daylight Saving Time has been justified as an energy-conservation measure.

Apparently unaware of a 1976 study by the National Bureau of Standards concluding that Daylight Saving Time produces no energy savings, the sponsors of the Energy Security Act of 2005, which extended Daylight Saving Time by an additional four weeks, included a provision in the bill ordering the Department of Energy to submit a report to Congress on whether Daylight Saving Time actually reduces energy usage. The wheels of bureaucracy turn slowly, and the report has not yet been released.

Fortunately, however, we don't have to hold our collective breath until the Energy Department makes its results known. Others have studied the question and have found not only that Daylight Saving Time does not save energy but that it may cause energy consumption to rise.

A working paper circulated in February by Matthew Kotchen and Laura Grant, economists at the University of CaliforniaSanta Barbara, reports the results of a careful study of the energy bills of Indiana households during the more than 30-year period prior to 2006 when the state operated under three time regimes. The sample included 77 counties on Eastern Standard Time that did not adopt Daylight Saving Time, five Eastern Standard counties that did, and 10 counties on Central Standard Time that also opted to "save" daylight (and, presumably, energy). Additional evidence was based on energy usage after the early 2006 imposition of Daylight Saving Time statewide, when several counties simultaneously switched from Eastern Standard Time to Central Standard Time.

The study showed a small but nevertheless statistically significant increase in residential electricity demand during the months when Daylight Saving Time was in effect, especially during the fall, as the return to standard time approached. On average, holding other determinants of electricity consumption constant, household electricity bills were $3.19 higher per year with Daylight Saving Time than without. Although an increase of $3.19 per household per year might not be worth worrying about, the Daylight Saving Time tax amounted to more than $8.6 million statewide when all of the Indiana households in the counties that operated on Daylight Saving Time were included.

According to the authors of the study, Daylight Saving Time raises energy usage overall because the potential savings from replacing artificial light with sunlight at the end of a summer's day are more than offset by the increased residential use of air conditioning (and of heating, as temperatures cool later in the season).

That conclusion confirms the results of a study published last year of the effects of a temporary extension of Daylight Saving Time during the 2000 Olympic Games in Sydney, Australia. That study found essentially no difference in energy consumption, owing to the fact that demand in the evening fell about as much as it rose in the morning.

Whether time is leaping forward or falling back, body clocks are thrown off. Productivity inevitably falls in the days following a switch, as people report groggily to work. And this year, perhaps, to the voting booth.

Some students of Daylight Saving Time suggest that accidents involving pedestrians increase immediately after the return to standard time because drivers have not yet adjusted to commuting home in the dark.

There are no benefits and some very real costs from switching to Daylight Saving Time in the spring and back to standard time in the fall. If we cannot persuade Congress to repeal the tyranny of time, politicians should at least stop justifying it on the basis of energy savings. Government edicts are not required for people to conserve. Energy consumption was reduced far more during the past year by higher crude oil and gasoline prices than it will ever be by the twice-a-year ritual of time travel.