Should Japan introduce daylight savings time?

After this summer’s intense heat waves, which left at least 110 people dead, some in Japan have become concerned about athletes’ safety during the 2020 Summer Olympic Games, which will be held in Tokyo in late July and early August – the hottest and most humid time of year in the country. One such person is Tokyo 2020 Olympics President Yoshiro Mori, who has proposed a solution: adopt daylight saving time (DST), so that events scheduled for the morning, such as the marathon, can be held during cooler hours. Would Japan benefit from such a change?

In much of the West, DST has long been used as a way to save energy and extend outdoor time for workers during the dark winter months and the hot summer months (though the European Union is now considering the elimination of DST, in the belief that it costs more than it saves, and owing to the effect on the human biorhythm). Given my extensive experience living in New England, I initially viewed the adoption of DST in Japan as a relatively straightforward solution – and not just to the Olympic issue. Japan depends on fossil fuels imported from abroad (especially the Middle East), so it has particularly strong incentive to minimize energy use.

Yet Mori’s proposal has been met with considerable opposition. One particularly convincing argument is that, given today’s technologies, it may not actually bring much in the way of energy savings.

According to the Ministry of Environment of Japan, one hour’s adjustment in 2008 would have led to savings of an estimated 0.910 million kiloliters of crude oil annually. Compared to Japan’s total energy consumption – 512 million kL of crude oil in 2016 – this is a drop in the bucket. If DST were implemented today, it would probably reduce energy consumption by less than 0.2%. In terms of emissions reductions, the impact would be similarly negligible.

To be sure, for a country that depends on imported energy, any savings are valuable. And the recent findings by the Intergovernmental Panel on Climate Change have shown that the threat from global warming, owing to reliance on fossil fuels, is even more urgent than previously known. But, given the potential complications associated with introducing DST, it is not clear whether this particular means of reducing energy consumption is worthwhile.

A concern that has attracted particular attention is the possibility that DST would result in people working longer hours. Japan’s business culture – centered on highly successful kaisha (firms) – is known to be very demanding, to the point that karoshi, or death from overwork or job-related exhaustion, is not uncommon. Critics of DST fear that, if the sun is still out at the end of business hours, managers will feel pressure to continue working and push their employees to do the same.

Japanese often cling to tradition, and men tend to have a particularly hard time adjusting to change. But, when it comes to implementing DST in Japan, it may not have to be all or nothing, as some of the country’s female leaders are proving.

Hokkaido, Japan’s northern island, has particularly long summer daylight hours, making the case for seasonal adjustment especially strong. That is why, in 2003, Governor Harumi Takahashi introduced an experimental and entirely voluntary schedule-adjustment plan that functions much like DST. Government offices, as well as firms, can choose to allow their employees to arrive at work and leave an hour earlier than normal during the summer months.

Another successful seasonal experiment was the “Cool Biz” policy introduced by Governor of Tokyo Yuriko Koike in 2005, when she was serving as minister of the environment. Japanese workplaces sacrificed some formality – allowing workers to wear short sleeves and no ties or jackets to the office – to enable office and retail buildings to minimize their use of air conditioning. Beyond changes to office temperatures and dress codes, Cool Biz offered some other energy-saving advice to businesses – including allowing employees to work earlier.

Given this, it is probably not surprising that Koike reportedly recognizes the potential benefits of introducing DST in Japan. Yet even she is hesitant about having the entire country change its clocks twice per year, especially if the main motivation relates to the 2020 Tokyo Olympics. More flexible solutions, like starting the marathon at an earlier hour, seem to be more convincing, from her perspective.

Whether or not Japan adopts DST, one message emerges from the debate. When it comes to making changes in change-resistant Japan, the ingenuity of Japan’s women leaders could well be what determines the future.