Why is the time changed twice a year
Twice a year we change the time to adapt to the so-called summer time and winter time. This practice has been practiced for years and, although many countries carry it out, there are also others who have chosen to dispense with this practice, which is motivated by the belief that it saves significant amounts of energy.
When the time is changed
The current schedule system is based on two schedules, the summer and the winter. The difference between one and the other is only one hour, so in reality it is a difference that, a priori, seems almost insignificant. The dates chosen for these changes depend on the days of the week, so they do not always fall on the same day of the calendar. Thus, summer time is adopted on the last Sunday in March , while winter time begins on the last Sunday in October .
The fact that the time is always changed on Sunday is not by chance, since these are the days when work activities are shorter, so the objective is that, although there are people who do work those, the Time change has as little influence as possible on day-to-day activity.
Why does the time change at 2 o’clock
Many people may wonder why the time is changed at 2 and not at another time. The reason is the same why it is done on Sunday and it is not another day of the week, and that is because that time is the one with the least work activity of the whole day.
The objective of this time change is to adopt day-to-day activities to the actual hours of sunlight , which, consequently, leads to lower lighting consumption and, with it, lower energy consumption .
From when the time is changed is Spain
This practice has been carried out in Spain since 1974 . It must be taken into account that, during the 20th century, a large part of electricity consumption was destined for lighting, so all measures to reduce its consumption and take advantage of natural sunlight were welcome.
However, currently there are conflicting positions regarding the time change, since a large part of the current energy consumption does not depend only on lighting, but on many other activities and, in addition, most work centers do not adapt their lighting to natural light. That is, they keep the lights on permanently regardless of the natural light that enters through the window. In this way, we can find people who are in favor of maintaining this time change between winter and summer and people who consider that it has more negative than positive consequences.
Proponents of time change claim that saving energy is reason enough to justify their practice. But the detractors consider that this energy saving, currently, is not particularly remarkable and this change has negative effects on health that makes it not a practice that should be maintained today.
The negative effects on health derive from the body’s need to adapt to the new schedule, which, even if it is only one hour apart, produces:
- Irregularities in sleep schedules.
- Irregularities in hunger schedules.
- Irregularities in the biological clock that regulates the circadian rhythm of sunrise and sunset.
These effects translate into negative consequences such as:
- Insomnia.
- Fatigue.
- Difficult to focus.
- Even, in some cases, disorientation.
These symptoms last an average of three days, which is how long it takes the human body to adapt to the new schedule, although in the case of older people and children these symptoms can last up to two weeks. After this time, the body gets used to the new rhythms and the biological clock adjusts without presenting major problems.
Regarding this question, there is no unanimous and concrete answer that allows the subject to be closed without any discussion. Some institutions such as IDEA (Institute for Energy Diversification and Saving) estimated the energy savings that the time change had in Spain in 2017 at more than 300 million euros.
On the other hand, there are also those who affirm that the problem of energy waste does not depend so much on the time change as on more efficient working hours, as well as the use of technologies and work routines that help save energy regardless of the time. In this sense, it is stated that the problem does not depend so much on working or doing daily life during the daylight hours but on replacing the light bulbs with more efficient equipment. An example is LED lighting, which makes it possible to take advantage of up to 90% of the energy expended in the form of light, losing only 10% of the energy in the form of heat, avoiding having meetings at the end of the day, or, simply, making use of natural light versus artificial light, a very simple action to carry out and which, currently, is not carried out in most work or education centers, and which is restricted only to the domestic environment in the best of the cases.
