Daylight saving time begins in Germany on the last Sunday in March at 2am. Clocks are moved forward by one hour to 3am, skipping the hour from 2am to 3am. Because this special feature is of course also visible in the time series on SMARD, we regularly receive questions about it, particularly in the days following the time change.

All time references on SMARD are related to the Central European Time (CET) in effect at the time in question. When the clock is moved forward, the skipped hour does not appear on SMARD.

Data collection continues unaffected, thus there are no “jumps” in the time series. If you move your mouse over the time series, however, you will notice in the pop-up window that on 31 March the hour from 1am to 3am is displayed, because the hour from 2am to 3am does not exist.

When downloading data you can also see that there is no hour from 2am to 3am on the day of the time change. This can cause confusion when, for example, comparing data over a longer period of time. When looking at day resolution, consumption and generation may also be noticeably lower on the day of the time change than on other Sundays.

Clocks are moved back again on the last Sunday in October, causing the hour from 2am to 3am to appear twice on SMARD. Looking at the year, the hour that was “lost” when the clocks were moved is regained.