Direct Energy Business
Market Data For Your Home Contact Us

How Daylight Saving Time Actually Influences Your Energy Costs

read | Share:

Next week, most of the United States will spring forward one hour and switch to daylight saving time. In the short run, that means a loss of sleep, decreased productivity at work, and a week or two of fatigue until your body clock resets. Yet, many of us would agree springing forward is worth the temporary discomfort because of the extra sunlight we gain in the evenings. 

It’s easy to see the personal benefits of more sunlight, but how else does the time change affect you and your business? While research on this subject has produced different results in different regions of the world, the consensus is that daylight saving time provides little or no benefit to homes and businesses – here’s why.

A Brief History

Most of the country is now accustomed to seasonal clock changes, but the biannual tradition is relatively new to American life. Here’s a brief history of daylight saving time in the United States:

  • During World War I, the U.S. implemented a daylight saving program for the first time as a conservation measure adopted at the time to support the war effort overseas.

  • During World War II, President Franklin Roosevelt temporarily revived daylight saving time, although the program had been unpopular during WWI.

  • After WWII, the federal program ended. Some states continued to change their clocks following their own schedules, while others observed standard time year-round. Of course, this state-by-state approach caused confusion.

  • In 1966, Congress established standard dates for springing forward and falling back to address the confusion among the states. 

  • In 2005, Congress introduced an act that both extended daylight saving time by four weeks and provided tax incentives for energy-saving measures such as fuel-efficient vehicles and energy-efficient home improvements. 

  • Today, there are still parts of the country that don’t observe daylight saving time, including Hawaii, American Samoa, Guam, Puerto Rico, the Virgin Islands and most of Arizona. 

Does Springing Forward Save Energy?

The observance of daylight saving time has fluctuated throughout U.S. history, ending with its four-week extension in 2005. However, the program’s key mission has remained the same: to reduce energy consumption in homes and businesses.

The main argument for daylight saving time is that it encourages people to use fewer lights on sunny summer evenings, thus decreasing their electricity use – and monthly bill. Older research supports this argument, such as a 1975 study performed by the U.S. Department of Transportation, which estimated a one percent decrease in electricity use at the beginning of daylight saving time. 

Yet, energy use patterns have since changed in the U.S., with the proliferation of air conditioning and electronic devices. Nowadays, people may use less energy on lighting during daylight time, but they likely offset that reduction with extra heating and cooling. Recent changes in energy use patterns bring up an interesting question: does daylight saving time really save energy anymore?

In the early 2000s, two regional studies cast doubt on the effectiveness of daylight saving time. In fact, the authors of both studies concluded that contrary to the program’s intentions, the time change may cause homeowners to use more energy from March to November.

  • A 2007 study performed by the State of California found extended daylight time resulted in only a 0.2 percent decrease in energy use within the state. This slight dip fell within the margin of error of 1.5 percent, meaning it’s possible that the extension caused a slight rise in energy use without showing up in the results.

  • A 2008 study on Indiana homes found that daylight saving time, which had recently been adopted statewide, resulted in a 1 percent increase in electricity consumption. The study estimated that daylight saving time cost Indiana homeowners an additional $9 million per year on their energy bills.

In 2008, a national study performed by the U.S. Department of Energy offered a more positive view on daylight saving. The study found that homes and businesses reduced electricity use by 0.5 percent each day during the four weeks of extended daylight time, or 0.03 percent annually. This daily saving may be much smaller than the 1 percent reported in the 1975 study, but it’s still enough to power 100,000 households or more than 15,000 businesses for a year.

Research is inconclusive on whether seasonal clock changes save or cost us energy. Despite conflicting results, the studies provide one shared takeaway: The impact of daylight saving time on energy use is modest.

Additional Impacts

Did you know that springing forward may affect more than just your energy use? Here’s a quick glance at the other impacts of daylight saving time.

  • Spending: In addition to energy conservation, daylight saving policies have aimed to increase consumer spending during summertime. In fact, businesses involved in sports, recreation and seasonal goods such as charcoal have continually pushed for extended daylight saving time, arguing that more sunlight would result in more sales. But a 2016 study from JPMorgan Chase found a problem with this argument: while credit card sales increased slightly in the spring in Los Angeles relative to Phoenix (a city that doesn’t set its clocks ahead), a greater dip in spending was experienced in the fall. The study also compared spending in San Diego and Denver to Phoenix but obtained different results, leading the authors to conclude that the “economic impact of DST is not uniform.”

  • Health and Productivity: It’s normal to feel a bit groggy after losing an hour of sleep, but the spring forward can have more significant effects on your health as well. First, the lost hour of sleep may cause a drop in productivity at work, with one study estimating a cost of about $434 million nationally. Second, the clock change may lead to a slight rise in heart attacks and strokes the following week. A study in Finland found that the rate of stroke increases by 8 percent on the Monday and Tuesday following the time shift, and a researcher from the University of Alabama found that the number of heart attacks rises by 10 percent during that same period.

  • Road Safety: The spring time change creates more hours of sunlight in the evening, when many people commute home from work. It’s reasonable to think that with more sunlight – and therefore better visibility of the road – commuters should suffer fewer accidents. However, research is mixed on whether daylight time improves road safety. A 2007 report by RAND Corporation analyzed 28 years of vehicle accident data and found that crashes involving pedestrians dropped by 8 to 11 percent during the first week of daylight time. Researchers in New Zealand, on the other hand, looked at data from 2005 to 2016 and found that crashes increased by 16 percent on the first Monday after the time shift and by 12 percent on the first Tuesday.


Although one goal of springing forward is to reduce energy consumption, you may not see a dip in your energy bill because of the clock change. Today, HVAC systems and electronic devices require a substantial amount of power year-round. But that doesn’t mean you can’t enjoy the extra sunlight while planning to save energy in other ways.


Posted: March 05, 2019