EU summer-time arrangements under Directive 2000/84/EC : ex-post impact assessment

The purpose of summer time is to capitalise on natural daylight. By turning the clock one hour forward as the days get longer in spring, sunset is delayed by this same hour, until the clock is set back again in autumn. This practice is applied in over 60 countries worldwide. In the EU, Member States draw on a long tradition of daylight saving time (DST), and many have developed their own DST schemes. Harmonisation attempts began in the 1970s, to facilitate the effective operation of the internal market. Today, the uniform EU-wide application of DST is governed by Directive 2000/84/EC; most European third countries have aligned their summer-time schemes with that of the EU. Much academic research has been invested in examining the benefits and inconveniences of DST. It appears that: - summer time benefits the internal market (notably the transport sector) and outdoor leisure activities, and it also generates marginal savings in energy consumption; - the impact on other economic sectors remains largely inconclusive; - with regard to inconveniences, health research associates DST with disruption to the human biorhythm ('circadian rhythm').