Settlement on ‘short’ clock change day: 27 March 2022

The clock change this weekend will result in a ‘short’ day which will impact Settlement periods and contract notifications. On a ‘short’ clock change day, there are only 46 Settlement Periods instead of the normal 48.

On Sunday 27 March 2022 from Greenwich Mean Time (GMT) to British Summer Time (BST) at 01:00 GMT). This means that the clocks go forward an hour, and the UK has a ‘short’ day.

In practice, this means that on this short day, BSC Settlement periods will be affected because there are only 46 Settlement periods instead of the usual 48. 

Submitting a contract notification

If you submit a contract notification which includes the clock change day and normal, non-clock change days, Energy Contract Volume Aggregation Agent (ECVAA) default rules apply.

The notified volumes corresponding to Settlement Periods three and four will be removed on the clock change day. Notified volumes for the remaining Settlement Periods on the clock change day will all be used for the Settlement Period, two Settlement Periods earlier than the one they were originally notified for.

If you submit a contract notification for the clock change day alone, the Settlement Periods in the contract notification should be numbered from 1 to 46.

Please note that contract notifications for the clock change day must contain the correct number of Settlement Periods as no defaulting rules will be applied to these notifications.

Impact on reports

The ECVAA Notification Report (ECVAA-I014) for 27 March 2022 will only contain 46 Settlement Periods and will include the effect of any defaulting rules applied to multi-day notifications.

The ECVAA Forward Contract Report (ECVAA-I022) for 27 March 2022 will show a representation of the original notifications submitted.


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