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’. The LDSO must then calculate the LLFs according to their approved methodology statement. An audit of the LLF calculations is required to ensure that they are consistent with the approved methodology.

This Calculation Self Assessment Document (CSAD) is designed to gather factual information about the compliance of the LLF Calculations 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 Applicability Section.

LDSOs should provide information to which GSP Groups and Methodology the calculation applies to.

1.3 Calculations 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 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 Applicants can provide any additional information that they consider to be relevant to their application.

Appendix 9 should accompany this document if site specific LLFs were recalculated.

1.1 General Information

Distribution Company Name:

We confirm that:

• the Line Loss Factor Calculation Self-Assessment Document (CSAD) is 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): _________________________

Methodology Statement Name:

Publication Date:

Version No.:

Distribution Area(s) (GSP Group(s)) to which methodology is applicable to:

Are the LLFs calculated in accordance with the methodology statement detailed above?

Yes/No (delete as appropriate)

Please provide reasons for the mid-year LLF submission.

Have you re-calculated site specific LLFs for this mid-year submission?

If so please provide details.

Have you re-calculated generic LLFs for this mid-year submission?

If so please provide details.

1

Data Request for Site Specific LLF re-calculations

If site specific LLFs were re-calculated, please provide the calculation details in Appendix 9.

2

Data Request for Generic LLF re-calculations

If generic LLFs were recalculated, Please provide a copy of the live model used to calculate your generic LLFs and the input data that supports Principle 9 of BSCP128.

Where the data set is very large a subset of the data can be provided to demonstrate the year period used.

A brief commentary should be included to explain why you believe the LLFs are an accurate reflection of the losses for the network at each voltage level.

Where applicable, explain why use of Generic LLFs remains applicable instead of Site Specific LLFs if Principle 17 of BSCP128 applies

3

Please complete Appendix 5 for all Site Specific and Generic LLFs as detailed in question 1 and 2.

Appendix 5 contains two sub-documents CSAD 2.1 and CSAD 2.2. If site specific LLFs were re-calculated, please provide these details in CSAD2.1. If generic LLFs were re-calculated, please provide these details in CSAD2.2.

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 6 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 6 of BSCP128.

7

Are the start dates for all re-calculated LLFs in line with the site go-live dates?

Please provide details on the LLF and site go-live dates.

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 in accordance with BSCP128. Please confirm that all LLFs are calculated to at least 3 d.p. in all files submitted.

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 LLFs that have significantly changed from the last submission of LLFs?

If so, please provide details.

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.

Evidence should include details of how this validation has been carried out and supporting rationale for the change in LLF Values.

9d

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

If so, please provide details.

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 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.

Evidence should include details of how this validation has been carried out and supporting rationale for the change in LLF Values.

10

Have the 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 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 in to their working instructions and/or process maps, including details on the error checking processes used in the calculation process.

12

Are there any SVA or CVA Site Specific sites for which a default calculation, or default replacement process was undertaken?

If so, please give details.

SVA or CVA Site specific LLFCs for which a default calculation or default replacement was applied have to be documented and provided to the BSCCo auditor upon request. Any failure to do so will lead to a non- compliance.

For example SVA or CVA sites where for a given SToD period instead of applying calculated LLF, a calculation was performed using a defined threshold (e.g. 200 kVA) or a generic LLF was applied.

13

Are there any Sites with multiple connections to the Total System where the primary connection is at EHV but there is a subordinate connection that Principle 17 (a)-(b) would apply to and for which a default calculation, or default replacement process was undertaken?

If so, please give details.

Subordinate connections for which a default calculation or default replacement was applied have to be documented and provided to the BSCCo auditor upon request. Any failure to do so will lead to a non- compliance.

For example connections where for a given SToD period instead of applying Site Specific LLF, a generic LLF was applied.

14

Does the calculation involve third parties?

If so please provide details.

Where aspects of the calculation 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 Calculations can be added here or appended to the document.

Version

Date

Description of Changes

Changes Included

Mods/ Panel/ Committee Refs

1.0

26/06/14

First Published June 2014 Release

CP1407 v2.0

ISG157/01

SVG160/05

P225/12

2.0

22/02/18

February 2018 Release

CP1492

ISG198/06

SVG200/04

3.0

27/02/20

February 2020 Release

CP1519

ISG221/05

SVG224/04

4.0

01/09/21

1 September 2021 Non-Standard Release

P420

P316/05

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