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The Pros and Cons of Daylight Saving Time

In a few countries, DST has become a political power struggle, while others debate whether setting the clocks one hour ahead in the spring has the intended effect of conserving energy or reducing road accidents.

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DST affects milking the cows.

Traditional dairy farmers often protest that DST makes milking cows and getting the milk collected in time a challenge.


Ever since the very first time Daylight Saving Time (DST) was introduced about 100 years ago, people have disagreed about whether setting the clocks one hour forward in the spring and back again in the fall has the desired effect.

DST Changes — Dates and Local Times

More Natural Light

Over 70 countries use DST today, mainly to:

  • Make better use of natural daylight.
  • Conserve energy otherwise spent on artificial light.
  • Decrease road accidents by making sure roads are naturally lit during the hours with most traffic.

DST Statistics — Past and Present Use

Daylight Hours Vary

The argument of adding an hour to standard time in the spring to make better use of natural daylight in the evenings makes the most sense in areas furthest away from the Earth's Equator. This is where there is the biggest difference in the number of daylight hours in winter and summer.

Daylight Hours Examples:

  1. Sunrise & Sunset in Tromsø, Norway
  2. Sunrise & Sunset in Seattle, USA
  3. Sunrise & Sunset in Quito, Ecuador
  4. Sunrise & Sunset in Cape Town, South Africa

Upsets Milking Cows

Traditional dairy farmers often protest that changing the clocks one hour twice a year makes milking cows and getting the milk collected in time a challenge. In more modern dairy farms, the cows are milked at will by robots and this argument becomes void. However, farmers in developing countries are still an active part of the debate.

Presidential Power Struggle

Since January 2011, Russia has been through several changes in their DST schedule, causing both protests and unrest, before President Vladimir Putin decided to return to permanent standard time (aka winter time) in October 2014.

Where Will DST Start or End Next?

In other countries, such as Egypt, the authorities often change DST dates.

In Muslim countries, like Morocco, DST is suspended during Ramadan and started again once the month is over.

Losing US Popularity

According to a Rasmussen Report from 2013, only 37% of Americans see the purpose of DST compared to 45% the year before.

There are many positives to the extra hour of daylight, especially in everyday life:

  • Studies link DST to reduced road injuries. A joint Transport Research Laboratory and University College of London study predicted that fewer people would be killed and injured in road accidents if one hour of daylight was transferred from the morning to the afternoon.
  • The tourist industry welcomes DST, claiming that the extra hour of sunlight makes people stay out later, thus spending more money on activities like festivals, shopping and concerts. The Belfast Telegraph reports that the extra evening light gives Northern Ireland at least £6.34 million a year in extra cash from tourists.

  • In Australia, the New South Wales state government announced that an extra four weeks of DST would boost retail and tourism. According to the Courier Mail, Queensland's lack of Daylight Saving is costing the economy an estimated $4 billion a year in lost business.

Energy Efficient, or Not?

DST is often linked to energy saving, but there is still disagreement as to whether the theory matches practice.

  • Pro DST arguments are that more light can counteract blackouts and other electrical failures that can occur later in the day and that it influences people to spend more time out of the house, thus using less lighting and electrical appliances.
  • In countries such as Cuba, Chile, Argentina, Mexico, the United States, and other parts of the world, DST is used as a means of conserving energy as the demand for electricity and gas increases.

Arguments against DST include:

  • Safety concerns – People are leaving their homes when it is still dark in the mornings, thus being exposed to crime. Guatemala decided not to have DST in 2008 because of safety concerns.
  • Health concerns – Studies show that there is an increase in both heart attacks and road accidents on the days after clocks are set forward one hour in the spring.

Topics: Daylight Saving Time, Timekeeping

In This Article


Daylight Saving Time – DST

  1. What is DST?
  2. One Hour Back or Forward?
  3. What is Standard Time?
  4. Savings or Saving?
  5. Pros and Cons of DST
  6. Your Health and DST
  7. Summer or Winter Time?
  8. History of DST
  9. History of DST in Europe
  10. DST Statistics

Time Zones & DST

Daylight Saving Time Changes:

Sunrise & Sunset Times

Time Zone Library

  1. What is a Time Zone?
  2. How Many Time Zones Are There?
  3. Half Hour & 45 Minute Time Zones
  4. What is Standard Time?
  5. What's the International Date Line?
  6. When Were Time Zones Introduced?
  7. USA Time Zones
  8. UK's Time Zones: GMT and BST
  9. Canada's Time Zones
  10. Australia’s Time Zones
  11. Antarctica's Time Zones

Time Zones Worldwide

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