British Summer Time is the UK’s rendition of the ever-controversial concept of Daylight-Saving Time (DST). With the EU counting down to a co-ordinated end to DST in 2021, just after the end of the Brexit transition period, the jury is out on what the UK will do next. Here, I explore some of the issues around this question.

A brief history of Daylight Saving Time in the UK #

The year was 1895. George Hudson was beginning to cause quite a stir on the New Zealand time-keeping scene. A Post Office worker by trade yet an astronomer and insect scientist by passion, Hudson cared about the opportunity to utilise daylight hours to their fullest. He presented his case to the Wellington Philosophical Society. From Transactions and Proceedings of the Royal Society of New Zealand 1868-1961:

George Hudson: postal clerk, insect scientist, astronomer
We cannot individually alter our times of going to bed or getting up, but must fall in with the habits of the majority ... those who desire to utilise the early-morning daylight are compelled to take some of their recreation before their daily work and some afterwards, which in many cases results in their having to forego pursuits that they would be enabled to follow successfully if their daylight leisure were continuous.

Though Hudson seems to be the first to write this idea down in so many words, it took tens of years, a world war, and persistent campaigning by other proponents of the idea for DST to be implemented anywhere in the world.

1916 British Summer Time was adopted (Summer Time Act 1916), after Germany had already implemented DST. The purpose at the time was to preserve coal (sunlight at more appropriate hours means less artificial light).
1941-1945 Clocks were brought forward an extra hour during world war two (GMT+1 in winter, GMT+2 in summer, ‘British Double Summer Time’)
1968-1971 The UK experimented with year-round GMT+1 (‘the British Standard Time experiment’)
1997 The EU started prescribing the clock change and the dates on which it should happen throughout its member states (Eighth Directive 97/44/EC on summer-time arrangements)

British Standard Time Experiment #

We can gain some insights about our question by looking back on the British Standard Time experiment and the House of Commons British Standard Time debate that followed. The experiment was largely met with a ‘shrug’ by the UK public

60% had no strong views, 35% were in favour of retaining the new system, 5% were against the new system [ref]

The rest of the debate was similarly inconclusive:

  • Some concluded from the experiment that road accidents had decreased though others were quick to point out that the breathalyser was introduced shortly before the experiment began, complicating the analysis. Analysis tried to avoid this complication by only looking at the change in accidents in two ‘rush hour’ windows, arguing that drunk driving accidents typically happen later at night. (The Potential Effects On Road Casualties Of Double British Summer Time — 2.1)
  • Manual labourers, especially in the north, as well as postmen who had to do morning deliveries, complained of going to work in the dark
  • Some mothers complained that their children had to travel to school in the dark. Others enjoyed that their children were coming home in the brighter hours of the afternoon.
  • Many argued that the additional time for leisure activities provided by year-round GMT+1 was particularly important. (Recall, this is the same argument George Hudson used when he first argued for DST)
  • Farmers were against the change. Or, wait, were they in favour of it?

The Scotland problem #

The country was also divided by it’s wide range of latitude (north-ness). Daylight hours change with the seasons and do so more dramatically the further you are from the equator. This means there is a stark difference between the daylight hours of England and Scotland:

  Shortest Day Longest Day
Edinburgh 7 hours 17 ½ hours
London 8 hours 16 ½ hours

This makes having a daylight saving period more appealing in Scotland because it’s harder to find a single time zone there that works all year round without either wasting morning daylight in summer or having some very dark mornings in winter. During the experiment, Edinburgh would have days where there was no Daylight until 9:43 (whilst London would have daylight from 9:06).

Further Considerations #

Of course, a lot has changed since 1970 and the public debate has continued on whether we should keep fiddling our clocks. Parliament has many times debated changes to the system, notably including the failed Daylight Saving Bill 2010. These have repeatedly failed or ran out of parliamentary time. Further considerations on the issue have included:

Energy #

There are many hunches one can form around how changing BST would impact energy usage:

  • Synchronisation with mainland Europe could lead to increased peak-time energy costs since peaks will be shared across UK and Europe. The UK imports about 5% of its electricity from France, and also imports from the Netherlands and Belgium.
  • BST might cause some to wake up earlier when it’s not warm or bright yet and so could increase heating and lighting costs in the morning.
  • If morning hours are dark, people may forget to turn off lights when they leave for work.

The ambitious can attempt to quantify the effects. In 2010, Cambridge University Engineering Department estimated overall energy savings of 0.3% in winter months if we were to adopt BST all year round. This isn’t an especially compelling result, though the authors suggest that they have adopted “a conservative approach such that they consider them lower bounds on any true savings.”

Sleep and Health #

There has been some suggestion of a spike in heart attacks (or ‘accute myocardial infarctions’, if you must) the week after we lose an hour of sleep, at least in the US. Later research has suggested that the net incidence of heart attacks is roughly unaffected, due to the corresponding drop when we gain an hour of sleep.

The EU pulls the plug #

Despite the confusion and lack of conclusion, European Parliament have made progress on a law that sees all member states ditch daylight savings time, after they ran a public consultation (which was curiously responded to overwhelmingly by Germans). Each state will have the choice of whether to keep permanent summer time or permanent standard time but will have their last clock change for daylight saving in 2021. The legislation at the EU level allows for a coordinated end to daylight saving time in Europe.

This leaves a bit of a question mark for the UK as the Brexit transitionary period, during which it is subject to EU law, is due to end juuust before 2021. Assuming the EU law does get passed, feasible options for the UK are:

  • Ignore the EU and crack on with what we already have
  • Join the EU in ending DST and use permanent GMT+1 (‘summer time’)
  • Join the EU in ending DST and use permanent GMT (‘winter time’)

Flexibility #

Those in search of a ‘correct’ answer to this question will be disappointed. Changing the clocks in one way benefits some and disadvantages others. Putting the clocks forward may benefit golf-players and disadvantage postmen. Putting the clocks back may benefit farmers who need to feed fussy cows and disadvantage those driving home at 5pm. This balance is inherent in trying to change behaviour at such a global level. Should we really be surprised that the schedules we’ve gotten used to over the past 80 years are on average about right?

Many criticisms of Daylight Saving Time are really criticisms of an inflexible system of work.

Daylight saving time does not give anyone any more time between between sunrise and sunset. Rather unfortunately, that is set by nature alone. Daylight Saving Time exists to nudge the nation toward taking advantage of changing daylight hours with the seasons, to shift our rigid routines. Perhaps those routines need to be a little less rigid in the first place. George Hudson’s claim that “we cannot individually alter our times of going to bed or getting up, but must fall in with the habits of the majority” may not be so true anymore, and perhaps we should try re-evaluating smaller changes we can make.

We don’t stick to the same routine all year round because it doesn’t work all year round. Similarly, not everyone should work to a 9-5 routine because it doesn’t work for everyone.