When the clocks go forward an hour, like every spring, there are debates about whether or not to abolish daylight saving time. Its detractors argue that the clock change has an impact on our health due to sleep disturbances. However, proponents claim that longer days save electricity, thereby reducing our use of man-made energy.
The start of daylight saving time has divisions among scientists.
This was the original intention of introducing daylight saving time. From our point of view, however, it makes sense to look not only at the impact on lighting electricity savings, but also at the total energy consumption of a building.
Sven Eggimann from Empa’s Urban Energy Systems Laboratory.
The Empa team carried out research to determine if and how the time change affects heating and cooling energy consumption. The results, “Climate change changes the trade-off between lower cooling demand and higher heating demand from daylight saving time in office buildingswere published in Environmental Research Letters.
In their paper, the researchers state:The original intention of daylight saving time was to save the energy needed for artificial lighting. However, this one-hour shift in opening hours also has an impact on the current and future demand for heating and cooling of buildings, which has not yet been fully studied.“.
The team therefore hypothesized that employees start working an hour earlier during daylight saving time, which means they also leave the office later in the afternoon. Since most of the cooling occurs in the late afternoon, these measures can save a lot of energy.
As office buildings become more energy efficient, cooling is naturally reduced or turned off altogether. To test this claim, the researchers simulated the heating and cooling energy used during daylight saving time and compared it to the results obtained outside these hours.
To fairly test their hypothesis, they analyzed different climate regions based on various data from office buildings in 15 US cities. To integrate the influence of climate change, they considered current and future climate scenarios up to 2050, which is crucial due to the impact of climate change on the energy consumption of buildings. For example, in one of their first studies, Empa researchers found that Switzerland’s demand for cooling could match that for heating due to climate change.
What does the study conclude?
The results of the new study highlight the benefits of saving daylight.
Daylight saving time can reduce the cooling energy of an office building by up to 6%. At the same time, heating demand could increase by up to 4.4% due to the earlier start of work in the morning.
However, since much more energy is needed for cooling than for heating in summer, changing the clock has an overall positive effect on the energy balance of a building.
In different types of climates and scenarios, the total energy savings vary slightly. On average, they were around 3% in most regions, but the amount of energy saved was evident in all regions.
Although only the results in the United States are detailed, this study makes it possible to analyze the results of energy savings in Switzerland, since the climatic conditions are comparable for several of the simulated climatic zones.
Protect the climate with energy saving measures.
Our study shows that the time change can contribute to climate protection. In the debate on the abolition of summer time, policy makers should take into account the electricity savings in artificial lighting and the impact on the energy balance of office buildings as a whole.
When assessing the impact of policies to change work routines, climate change and future heating and cooling demand will play a distinct role: a warmer climate has been shown to generally reduce the potential relative savings in office energy demand resulting from a change in working hours. models, while achieving similar absolute reductions.
Finally, the researchers pointed out that daylight saving time is just one of many methods that can be used to reduce energy consumption in buildings. Technical improvements, changes in behavior and a general arrangement of employees’ working hours can also contribute to energy savings and thus reduce CO2 emissions, whether the timetable changes every six months or not.
“However, what this study clearly shows is that, in the debate around daylight saving time, policy makers should reconsider the initial policy intention to save energy by taking into account the demand for energy. energy for space heating and cooling, and at the same time. climate changeconclude the researchers.
More information: iopscience.iop.org
Summer time history.
Daylight saving time is a measure implemented in many countries around the world to adjust working hours and make better use of daylight during the summer months. The idea behind daylight saving time is to move the clock forward one hour during the summer months so that daylight hours more closely match times when people are awake and active. This is believed to reduce electrical power consumption and in some cases can reduce traffic accidents and improve people’s quality of life.
The idea of daylight saving time was first proposed by Benjamin Franklin in 1784, but it didn’t become common practice until the early 20th century. The first country to officially adopt daylight saving time was Germany in 1916, during World War I. The measure was adopted to save energy and resources during the war, and soon other European countries like Britain and France also adopted it.
In North America, daylight saving time was first adopted in 1918, also as an energy saving measure during World War I. However, the measure was not popular and was dropped after the war. During World War II, daylight saving time was reintroduced in many countries, including the United States and Great Britain.
After the war, many countries abandoned DST again, but some kept it and it spread to other countries around the world. Currently, more than 70 countries regularly use daylight saving time, although some have removed or modified it in recent years due to criticism of its effectiveness and potential negative health effects.