1.3 Principles Review
Question	Guidance	LDSO Response: Y/N	Reference to supporting evidence in methodology
1a. Sites that are connected at EHV shall have Site Specific LLFs. How does the methodology comply with this principle?	EHV – Extra High Voltage and Site Specific are defined in BSCP128 please refer to the defined terms. Evidence should include how the LDSO determines sites to be connected at EHV.
1b. Where the customer has requested Site Specific LLFs and the LDSO is in agreement with this request the LDSO shall calculate and assign a Site Specific LLF. How does the methodology comply with this principle?	Evidence will be required to detail correspondence between the customer and the LDSO. The relevant MSIDs shall also be provided.
2. All LLFs must be calculated to at least 3 decimal places (d.p.) and submitted to 3 d.p. How does the methodology comply with this principle?	Evidence shall be provided to clearly state that the LLFs will be calculated to at least 3 decimal places.
3. All Site Specific LLFs shall account for Technical Losses only. How does the methodology comply with this principle?	‘Technical Losses’ is defined in BSCP128 please refer to the defined terms. The LDSO should include a high level description of the calculation method and model used to calculate Site Specific LLFs.
4. Generic LLFs shall account for all Losses (Technical and Non Technical) in the distribution area. How does the methodology comply with this principle?	‘Technical’ and ‘Non Technical losses’ are defined in BSCP128 please refer to the defined terms. The LDSO should include a high level description of the calculation method and model used to calculate Generic LLFs.
5. Site Specific LLFs and the total GSP Group losses shall be considered in the calculation of Generic LLFs. How does the methodology comply with this principle?	Evidence shall be provided on how the calculation uses both losses associated with MSIDs with Site Specific LLFs and Settlement Data of the relevant GSP Group losses.
6. Non-EHV Generic LLFCs for Import and Export at the same site where the voltage level is the same shall have the same values. How does the methodology comply with this principle?	Examples of evidence can include MSIDs for sites with Import and Export at the same voltage.
7a. There shall be no more than 2 Low Voltage (LV) LLFC Groups, in each GSP Group. How does the methodology comply with this principle?	Low Voltage is defined in BSCP128, please refer to the defined terms. Evidence should include the LLFC Groups used.
7b. There shall be no more than 2 High Voltage (HV) LLFC Groups, in each GSP Group. How does the methodology comply with this principle?	High Voltage is defined in BSCP128, please refer to the defined terms. Evidence should include the LLFC Groups used.
7c. There shall be at least 1 Generic EHV LLFC Group in each GSP Group. How does the methodology comply with this principle?	EHV – Extra High Voltage is defined in BSCP128, please refer to the defined terms. Evidence should include the LLFC Group(s) used.
8. As a minimum, Generic LLFs shall be calculated separately for Day and Night. How does the methodology comply with this principle?	‘Day and Night’ is defined in BSCP128 please refer to the defined terms. The methodology statement will be required to define ‘Day and Night’, LDSOs may also have greater granularity above ‘Day and Night’. Evidence will require a specific statement from the methodology and its location.
9. LDSOs shall utilise Settlement data from a Settlement Run at R3 or greater and from a complete 12-month period, for calculating Generic LLFs. The 12-month period to be used shall be the BSC Year¹ 3 years prior to the BSC Year for which the LLFs are being calculated. How does the methodology comply with this principle?	Evidence shall be provided on what data the methodology specifies the calculation to use
10. Adjustments to LLFs, to take into account historic market wide issues noted in the BSC Auditor’s latest Report, can only be made if agreed to be appropriate by the Panel. How does the methodology comply with this principle?	Evidence shall be provided on how the methodology takes into account any Panel decisions with regards to market issues and the calculation of LLFs.
11. Robust error detection and correction processes shall be in place throughout the calculation and submission of LLFs. How does the methodology comply with this principle?	Evidence shall be provided on what quality management systems and control techniques the methodology describes in the calculation of LLFs
12. All Generic LLFs shall be re-calculated at least every 2 years? How does the methodology comply with this principle?	Evidence shall be provided on the frequency of re-calculation or criteria used to determine how often the Generic LLFs are calculated.
13. All Site Specific LLFs shall be re-calculated when there has been a relevant change to the site or network, and at least every 5 years? How does the methodology comply with this principle?	Evidence shall be provided on the frequency of re-calculation or criteria used to determine how often Site Specific LLFs are calculated.
14. No changes shall be made to approved Generic LLFs mid year. Annual updates will have an effective from date of 1 April. Where default LLFs have been applied due to an audit failure, these may be replaced with approved LLFs on a prospective basis as determined when the LLFs resubmitted by the LDSO have been approved by the Panel. How does the methodology comply with this principle?	The principle must be included in the methodology statement.
15. No retrospective changes shall be made to approved Site Specific LLFs or Generic LLFs. How does the methodology comply with this principle?	The principle must be included in the methodology statement.
16. Changes shall only be made to approved Site Specific LLFs mid year if there has been a material change affecting the site; and the revised LLFs have been approved by the Panel. How does the methodology comply with this principle?	The principle must be included in the methodology statement.
17. Where the usage profile for a given site contains insufficiently large consumption or generation volumes to enable calculation of realistic Site Specific LLFs then a default calculation, or default replacement process shall be undertaken. How does the methodology comply with this principle?	An Audit trail of LLFCs where such a default has been undertaken, together with the rationale for defaulting, shall be maintained and be available to the BSCCo auditor upon request.
17a. Where a Site has multiple connections to the Total System and the primary connection is at EHV, LDSOs may use a generic LLF for subordinate connections that Principle 17 (a)-(b) would apply to in specific circumstances. How does the methodology comply with this principle?	EHV – Extra High Voltage and Site Specific are defined in BSCP128 please refer to the defined terms. Evidence should include how the LDSO determines the Site’s primary connection to be connected at EHV and that Principle 17 (a)-(b) would apply to the subordinate connection. Evidence should include how the Generic LLF used for the subordinate connection satisfies the conditions of Principle 17 (a) - (b).
Is there any additional detail you would like to add to your response?	Additional information that supports the review of the Methodology Statement can be added here or appended to the document.

CONTENTS

BSCP128 Appendix 01: Methodology Self Assessment Document (MSAD) for host LDSOs and Embedded LDSOs that do not Mirror V4.0

Defined Terms

Cross-references