Summer time begins on Sunday, 30 March 2014; when clocks are set one hour ahead at 02:00 am.

Summer time ends on Sunday, 26 October 2014; clocks are set back one hour at 03:00 am.

Transitions to/from summer time affect the use of the SESAM web client and the contents of Ediel messages, which are always recorded in standard time: UTC+1.

This notice presents information regarding how data is to be reported.

Terms and definitions
UTC:	Universal Time Coordinated, corresponds to Greenwich Mean Time (GMT).
Standard time:	Standard time in Norway is UTC+1.
Local time:	Time used daily (clock time) In winter = UTC +1 (standard time) In summer = UTC+2 (summer time).
SESAM:	System for Electricity Spot Auction Market – the trading and price calculation system for Elspot.

 

Common day-ahead price calculation:  refers to the system launched by NWE on 4 February 2014

Common day-ahead price calculation and programs use local time, all year round. On transition from standard time to summer time, results will be published for 23 hours. And on transition from summer time to standard time, results will be published for 25 individual hours.

EDIFACT message set D. 96 A:

1. Days with standard time
Days have 24 hours.

For an entire day in Standard time, Ediel messages have hourly values of:
00:00 to 24:00 (UTC + 1).

2. Transition day from standard time to summer time
Because local clocks are set one hour ahead, the day comprises only 23 hours. On this day,the common day-ahead price calculation and programs only cover 23 hours.

For an entire day in standard time, Ediel messages have hourly values of:
00:00 (UTC + 1) to 23:00 (UTC + 2).

3. Days during summer time
Days have 24 hours. There is a 1-hour difference between local time and Standard time. The common day-ahead price calculation and programs are using local time.

For an entire day in standard time, Ediel messages have hourly values of:
23:00 to 23:00 (UTC + 2).

4. Transition day from summer time to standard time
Since clocks are turned back one hour, the day contains 25 hours. The common day-ahead price calculation and programs cover 25 hours. 25 hours must be reported and two hours (called 3a and 3b) between 02:00 and 03:00 on 26 October may be treated as two different hours.

For an entire day in standard time, Ediel messages have hourly values of:23:00 (UTC + 2) to 24:00 (UTC + 1).

SESAM Web
For the transition from standard time to summer time, SESAM web users can enter their bids only with 23 hours, the DST-shift-hour 02:00-03:00 is not showing.

For the transition from summer time to standard time, SESAM web users can enter their bids with 25 hours. DST double hours can be individual, that is if hours 3a and 3b don’t have to have same volumes.

FTP server files
At the transition from standard time to summer time, data for hour 03:00 will have no value (blank) for all .xls files, double semicolons (;;) will indicate hour 03:00 in .sdv files.

For the transition from summer time to standard time: .xls files will contain 25 hourly columns instead of 24 hourly columns as it is today. We will introduce an hour 3a and 3b in the text files. Column 3b will only be used when we switch from summer to normal time. For rest of the year this column will be empty. This applies to all data, prices, volumes, production, consumption, and other entries.