Credit Assessment Load Factor (CALF)

Each BM Unit has a Credit Assessment Load Factor (CALF) value, which is a measure of their average generation/demand as a ratio of their maximum for the current BSC Season. These values are calculated seasonally for each BM Unit, and each Season’s values are published at the beginning of the preceding Season.

CALF is used in the Energy Indebtedness calculation along with Generation or Demand Capacity (GC/DC) until II data is available. An exception is for Interconnector BM Units and those Generation Units with Credit Qualifying status who instead use Physical Notifications during this period.

Further details on CALF and how it is calculated can be found in the  CALF Guidance Document.

What are the current CALF values?

Values for the upcoming Season, current Season, and two previous Seasons can be found on the ELEXON Portal.

Each BM Unit, except for Interconnector and Credit Qualifying BM Units, is given a CALF value for each Season. These are calculated based on the BM Unit’s performance in the previous equivalent Season (the Reference Season). For example, the Summer 2010 CALF values were calculated based on performance in Summer 2009. Values for a given Season are calculated and published three months beforehand.

What are Credit Qualifying BM Units?

Under Approved Modification P215 'Revised Credit Cover Methodology for Generating BM Units', some BM Units are classified as Credit Qualifying. These BM Units do not use the normal "CALF x GC/DC" method for calculating Energy Indebtedness, but instead use their Physical Notifications. As a result, they are not allocated a CALF value, but are given a default value for use if they happen to lose this status.

A list of the current Credit Qualifying BM Units are included within the lists of Seasonal CALF values available on the ELEXON Portal.

How can I request alternative CALF values?

If you are the Lead Party of a BM Unit and you feel the currently assigned CALF value is inappropriate, you can request an alternative value to be calculated. You can ask for a value to be calculated using the Holiday CALF or the SVA Embedded Generation methodologies, or you can request a CALF appeal. Details of each methodology and the forms for requesting them are all contained within the CALF Guidance Document.

Holiday CALF

Suppliers who experience reduced demand during the two Annual Holiday periods of Christmas/New Year and Easter can request a reduced CALF value to reflect this. Requests should be submitted to settlementoperations@elexon.co.uk by 10 Working Days before the relevant Season begins.

SVA Embedded Generation

Supplier BM Units that are mostly comprised of Embedded Generation can request this methodology to obtain a negative CALF value. If you are planning on applying this methodology to a BM Unit for the first time, you will need to contact us before the main appeal deadline below, as a CALF appeal may be required. For BM Units that already use this methodology, the forms should be sent to settlementoperations@elexon.co.uk by 10 Working Days before the Season begins.

CALF Appeals

If you wish to request an alternative CALF, and neither of the above methodologies apply, you will need to submit a CALF appeal. You will need to fill in the relevant pro-forma in the CALF Guidance Document, to detail the grounds of your appeal, and submit this to bscservicedesk@logica.com by the first Working Day of the month preceding the start of the Season. These appeals are then presented to the Imbalance Settlement Group (ISG) as a Confidential Paper.

When is the deadline for requesting alternative CALF values?

CALF appeals need to be taken to the ISG, so in order to process the appeal in time the deadline for submission is the first Working Day of the month preceding the start of the Season.

Requests for Holiday CALF and the SVA Embedded Generation methodology are laid out in the CALF Guidance Document, so an appeal is not usually needed. The deadline for these is 10 Working Days before the Season begins.

However, it is possible that a BM Unit requesting the SVA Embedded Generation methodology for the first time may need to be taken to ISG. If you are thinking of applying this to a BM Unit for the first time, you need to contact us by the main appeal deadline to check if an appeal will be needed.

The dates and deadlines for 2011 are given below:

A Newscast article containing the deadlines for each Season is sent out when the values are first published. A further reminder is sent out the week before the main appeal deadline.