Why do we change the time?

Pourquoi change-t-on l’heure ?
Why do we change the time?

Towards the end of winter, we move our clocks and watches forward to switch over to summer time. The custom is deeply rooted in our habits and routines. But what’s the actual purpose of changing the time?

A little history

It was the American scientist Benjamin Franklin who was the first to propose, back in 1784, a schedule shift with a view to saving energy. We had to wait until 1916 for a country – Germany, as it happened – to adopt the practice. In Canada, initial legislation on the matter was passed in 1918. And during the Second World War, the federal government instituted daylight saving time year round all across Canada.

Since 2006, daylight saving time has begun on the second Sunday of March and runs to the first Sunday of November.

Note that the time change falls under provincial jurisdiction. Thus, Saskatchewan is the only province in Canada not to set clocks back or ahead.

Energy savings

Originally, the idea of putting the clock forward in the summer allowed for synchronizing the hours when we’re awake — and active at work — with the hours of sunshine. It was also to reduce energy consumption by decreasing the use of lighting in the evening.

Nowadays that benefit is very limited, since lighting accounts for less than five percent of household electricity costs. And that figure is dropping even further thanks to new less-energy-consuming light bulbs. It’s now heating that’s the most important element in household electricity consumption, representing more than fifty percent of the bill, but its use is influenced above all by weather conditions.

Time change can affect the sleep cycle for two or three days. However, for more vulnerable people the change can have more harmful effects, including attention and eating disorders, a falling off in the capacity to work and an increase in levels of depression.

Why continue changing the time?

Barely twenty percent of the world’s population changes the time at any point during the year. If we know that the energy benefits are highly limited, we may well ask ourselves why we go on changing the time twice a year.

The principal reason is to remain in synch with the United States, our main economic partner. There’s also the tradition, which goes back almost a century.

Lastly, it’s a good reminder to change the batteries in our smoke detectors.

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