1. Introduction

Objectives of the CSAD

The Audit of Line Loss Factors seeks to provide additional transparency and consistency regarding the calculation and application of Line Loss Factors (LLFs) used in Settlement by creating a set of high level principles, which all LLF methodologies (created by Licensed Distribution System Operators (LDSOs)) must adhere to. The principles are detailed in BSCP128 ‘Production, Submission, Audit and Approval of Line Loss Factors’. For Embedded LDSOs that Mirror another LDSO’s methodology, they must obtain the LLFs (either from that LDSO or from the BSC Website), process the LLF data in accordance with their own valid Line Loss Factor Groups and Classes and submit them to BSCCo (the LLFs must be in accordance with the methodology approved by the Panel). An audit of the Embedded LDSO’s LLF calculations/processing is required to ensure that the LLFs are consistent requirements of the BSC Section K and BSCP128 (and in accordance with the approved methodology).

The Calculation Self Assessment Document for Embedded LDSOs who Mirror (CSAD) is designed to gather factual information about the compliance of the LLF calculations/processing and the methodology it applies to.

For any defined terms see BSCP128. All defined terms are initially capitalised. Any other terms please refer to the Balancing Settlement Code.

Guidance for completing the CSAD

The CSAD has been split into three sections as follows:

1.1 General Information

This section should be completed in full in respect of all questions.

1.2 Calculation/Processing Applicability Section.

Embedded LDSOs should provide information to which GSP Groups and LDSOs’ methodologies the calculation/processing applies to.

1.3 Calculations/Processing Assessment Section.

This section contains a series of questions, for each of which guidance is provided in order to either provide clarification or to set out the areas the response should address.

The Embedded LDSO should also indicate what evidence is available to support the responses given. This evidence will need to be available to BSCCo for the audit to review take place. References to ‘systems’ within the CSAD do not relate solely to the functionality of computer hardware and software, but extend to the supporting business and operational processes (including manual processes). The term ‘development’ in relation to a system refers to either the development of a new system or to any significant changes or upgrades in respect of an existing system.

The final question in this section is not mandatory and is provided so that Embedded LDSOs can provide any additional information that they consider to be relevant to their LLF and CSAD submission.

Appendix 5 should accompany this document showing the Site Specific and EHV generic supporting information for both CVA and SVA (if applicable) and the Generic supporting information.

Appendix 9 should be used after the BSCCo have identified the site specific LLFs to audit. Another template instead of Appendix 9 can be used as long as it aligns to the principles in BSCP128.

1.1 General Information

Distribution Company Name:

We confirm that:

• the Line Loss Factor Calculation Self-Assessment Documents (CSAD) are true, complete and accurate and not misleading because of any omission or ambiguity or for any other reason; and

• in our opinion, the arrangements as documented are adequate and appropriate for the provisions under the Balancing and Settlement Code Section K and BSCP128 ‘Production, Submission, Audit and Approval of Line Loss Factors.

Authorised Signature:

Name of Authorised Signatory:

(Category X as per BSCP38 ‘Authorisations’)

Password:

Date:

VERIFICATION OF DETAILS To be completed by BSCCo

DATE RECEIVED: _________________________

NAME AND PASSWORD/SIGNATURE VALID (Y/N): _________________________

Please give details of the relevant GSP Groups, as an Embedded LDSO, you are operating in:

GSP Group

Operating in this GSP Group?

_A Eastern

Yes/No

_B East Midlands

Yes/No

_C London

Yes/No

_D Merseyside and North Wales

Yes/No

_E Midlands

Yes/No

_F Northern

Yes/No

_G North Western

Yes/No

_H Southern

Yes/No

_J South Eastern

Yes/No

_K South Wales

Yes/No

_L South Western

Yes/No

_M Yorkshire

Yes/No

_N South Scotland

Yes/No

_P North Scotland

Yes/No

Are the LLFs for each GSP Group you are operating in obtained from the LDSO or the BSC Website? Please provide details on how you have obtained the LLFs by GSP Group.

Do you have any Site Specific sites/LLFs?

If so please provide details.

1a

Please provide details of the calculation method for Site Specific LLFs.

Please give a description of the calculation method used. This should include a reference to the location in the methodology statement.

The LDSO may wish to include an illustrative example as evidence.

If you have no Site Specific LLFs please indicate as N/A.

1b

Please provide details of the process steps for your calculation of Site Specific LLFs.

Please give a description of the end to end process for calculating Site Specific LLFs.

The LDSO may wish to include high level flow diagram of the process or internal working instructions that detail the process.

If you have no Site specific LLFs please indicate as N/A.

2a

Please provide details of how you have obtained the Host LDSO’s Generic LLFs. Split by Host LDSO and identify which GSP Group (s) the LLFs are applicable for.

Please give a description of the method used to obtain the Host LDSO’s Generic LLFs. This should include a reference to the location on either the BSC Website or how obtained from the Host LDSO’s website if applicable.

Split by GSP Group and Host LDSO

2b

Please provide details of the process steps for your manipulation of a Host LDSO’s Generic LLFs. If different by Host LDSO please give specific details.

Please give a description of the end to end process for the manipulation of the Host LDSO LLFs so as to construct you Generic LLFs submission by GSP Group.

LDSO may wish to include high level flow diagram of the process or internal working instructions that detail the process.

3

Please complete the table of information for all Site Specific and Generic LLFs as detailed in section 2.

Data can be submitted in Excel file format with your CSAD submission.

Section 2 is for supporting information for Site Specific and Generic data information submission. This information is used to aid the validation of the LLF data submission. LDSOs may choose to submit the information in Excel format as an attachment to the CSAD.

4

Have all changes or new SVA LLFC IDs been submitted into the Market Domain Data (MDD) change process (as per BSCP509)?

If so please give details.

Any changes or new LLFC IDs must be submitted through the MDD change process. The correct LLFC Ids (and supporting information) are required to be approved in MDD prior to submission of the SVA LLFs. LDSOs should confirm that the MDD Change Request Form(s) (with CR References) have been submitted (see BSCP509 for further details).

5

Have all SVA LLFs been submitted in the D0265 file format?

The file format for SVA LLF submission is detailed in Appendix 7 of BSCP128.

6

Have CVA LLFs been submitted in the specified long or short file format?

The file format for CVA LLF submission is detailed in Appendix 5 of BSCP128.

There are two formats that can be used, a long format detailing every Settlement Day and Settlement Period LLF and a short format detailing the LLF to be used for specified date ranges.

The file requires a checksum, further information on calculating the checksum is detailed in section Appendix 5 of BSCP128.

If CVA LLFs please indicate as N/A.

7

Are all LLFs submitted for start date 01 April (and start Settlement Period 1)?

If not please give details,

The annual submission of LLFs covers the period 01 April to 31 March. Confirmation is required that all LLFs in the submission start from Settlement Period 1 on 01 April.

Evidence will detail how this had been checked.

8

Are all LLFs calculated to at least 3 decimal places (d.p.) and submitted to 3 decimal places?

LLFs are required to be calculated to three decimal places. Please confirm that all LLFs are calculated to at least 3 d.p. in all files submitted.

Evidence should include details of how this validation has been carried out.

9a

Are all SVA LLFs ≥ 0.750 and ≤1.250?

Please confirm that all SVA LLFs are calculated within the range specified.

Evidence should include details of how this validation has been carried out.

9b

Are all CVA LLFs ≥0.750 and ≤1.250?

Please confirm that all CVA LLFs are calculated within the range specified.

Evidence should include details of how this validation has been carried out.

9c

Are there any SVA Site Specific LLFs that have significantly changed from the last submission of LLFs?

BSCCo would expect evidence to be provided for all LLFs which are expected to breach this tolerance.

BSCCo will be validating the SVA submission in accordance with BSCP128 Section 3.5 point 7 c). BSCCo will identify any LLF values that are outside of the range specified. BSCCo will request from the LDSO evidence for any values that fall outside of this range and supporting rationale to justify this change.

9d

Are there any CVA LLFs that have significantly changed from the last submission of LLFs?

BSCCo would expect evidence to be provided for all LLFs which are expected to breach this tolerance.

BSCCo will be validating the CVA submission in accordance with BSCP128 Section 3.5 point 7 d). BSCCo will identify any LLF values that are outside of the range specified. BSCCo will request from the LDSO evidence for any values that fall outside of this range and supporting rationale to justify this change.

9e

Are there any new Site Specific sites that were not included in last year’s submission?

If so, please give details.

Please provide information in 2.1 for any new Site Specific sites.

If you have no Site Specific sites please indicate as N/A.

10

Have any sites undergone a Relevant Change?

If so please provide details.

Relevant Changes are defined in BSCP128 as ‘A significant change to the physical plant, apparatus, distribution network, or capacity which causes a change to the Line Loss Factors’.

Information and supporting evidence should be detailed in the response. MSIDs should be flagged with the relevant information as in 2.1.

11

Please provide details of the error checking processes carried out when calculating/ manipulating LLFs.

LDSOs are required to have robust error detection and correction processes in place throughout the calculation of LLFs.

LDSOs may wish to provide references to their working instructions and/or process maps, including details on the error checking processes used in the calculation/manipulation process.

12

Have all Site Specific LLFs been calculated within the last 5 years?

Yes/No (delete as appropriate)

Site Specific LLFs must be calculated at least every 5 years. The cut off for the 5 year period is 30 September. Any failure to do so will lead to a non- compliance.

For example, the annual LLFs for 1 April 2011, with calculations submission date of 1 October 2010, any Site Specific LLFs calculated up to up to and including 30 September 2005 must have been re-calculated.

If you have no Site specific LLFs please indicate as N/A.

13

Have all Generic LLFs been calculated within the last 2 years?

Yes/No delete as appropriate)

Generic LLFs must be calculated at least every 2 years. The cut off for the 2 year period is 30 September. Any failure to do so will lead to a non- compliance.

For example, the annual LLFs for 1 April 2011, with calculations submission date of 1 October 2010, any LLFs calculated up to 30 September 2008 must be re-calculated.

14

Does the calculation/manipulation involve third parties?

If so please provide details

Where aspects of the calculation/manipulation are sub-contracted to a third party the activity should be detailed in the response field (description of process, process maps, quality checks, etc). The LDSO is still responsible for any elements that it has contracted out.

For example, a LDSO may utilise a third Party to generate the Site Specific LLFs for a particular site.

15

Is there any additional detail you would like to add to your response?

Additional information that supports the audit of the process can be added here or appended to the document.

Version

Date

Description of Changes

Changes Included

Mods/ Panel/ Committee Refs

1.0

20/04/09

First Published

P216

153/04

2.0

24/06/10

June 10 Release

CP1326

ISG111/03

SVG111/01

3.0

26/06/14

June 14 Release

CP1407 v2.0

ISG157/01

SVG160/05

P225/12

4.0

01/09/21

1 September 2021 Non-Standard Release

P420

P316/05

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