Primary BM Units are the units used under the Balancing and Settlement Code (BSC) to account for all energy that flows on or off the Total System (the Transmission System and each Distribution System combined). A Primary BM Unit is the smallest grouping of generation and / or demand equipment that can be independently metered for Settlement and all generation and demand equipment must be captured in a Primary BM Unit.

Secondary BM Units can be registered by Virtual Lead Parties (VLPs) and Asset Metering VLPs (AMVLPs). Supplier Volume Allocation (SVA) Half Hourly (HH) metered generation and / or demand equipment within a single Grid Supply Point (GSP) Group can be allocated to a Secondary BM Unit for the purpose of providing Balancing Services to the National Electricity Transmission System Operator (NETSO). This equipment will also be registered in a Primary BM Unit.

Where equipment is in both a Primary and Secondary BM Unit, the Supplier is responsible for balancingthe Settlement of the Primary BM Unit and should contract for all the energy required to balance that BM Unit. If the equipment is also in a Secondary BM Unit and is called upon by the NETSO for Balancing Services, Settlements will adjust the Primary BM Unit so that the Supplier is not affected.

Note that an SVA Metering System or an Asset Metering System must only be providing Balancing Services through one BM Unit (Primary or Secondary) at any particular time to prevent double counting in Settlement.

The BSC Section K and BSCP15: BM Unit Registration set out the requirements around the registration and configuration of tells you how to register Primary and Secondary BM Units. BM Units can also be registered on the Self-Service Gateway (Elexon Kinnect Customer Solution).

Accessing the Elexon Kinnect Customer Solution

As part of the Market Entry process you will be provided access to the Customer Solution. To register the relevant BM Units please log into the Elexon Kinnect Customer solution. You can complete and submit the information in the Customer Solution if you are a Category A signatory or complete the information as an Assistant and send it to a Category A signatory to approve and submit. For information on accessing the Elexon Kinnect Customer solutionKinnect, please refer to: ‘FAQs when using the Kinnect Customer Solution’.

Guidance is provided below on how to register the relevant BM Units for your role.

What do I need to do before I can register BM Units?

Before registering a BM Unit you need to complete or be in the process of completing Market Entry for the relevant BSC Party Role.

If you are registering a BM Unit for a Generating Unit that is associated with a Licensable Generating Plant, the BSC Party registering the Generating Unit must be the person that generates electricity at that Generating Plant. You will need to complete Market Entry as a Trading Party – Generator to register the BM Unit. If you are unsure if your activity is licensable please contact the Ofgem Licensing team at licensing@ofgem.gov.uk.

If you are registering a BM Unit for a Generating Unit that is associated with a Licence Exempt (Exemptable) Generating Plant, the BSC Party registering the Generating Unit can be either:

The person that generates electricity at that Generating Plant; or
Another BSC Party with the agreement of the person who generates the electricity at that Generating Plant.

You will need to complete Market Entry as either a Trading Party – Generator or Trading Party - Supplier to register the BM Unit. Note that you could register the Primary BM Unit to another BSC Party (e.g. a Supplier with whom a Generator may have a Power Purchasing Agreement (PPA) offtake arrangement) if you have a short timescale before the intended energisation date in which to go through the Market Entry process to qualify as a Generator.

If you are registering a BM Unit for trading over one of the Interconnectors, you need to complete Market Entry as a Trading Party – Interconnector

If you are registering Supplier BM Units you need to complete Market Entry as a Trading Party – Supplier.

If you are registering a Secondary BM Unit, you need to complete Market Entry as a Virtual Lead Party (VLP) or Asset Metering Virtual Lead Party (AMVLP).

Visit the Market Entry page or BSCP65: Registration of Parties and Exit Procedures for more details.

NETSO Requirements

If you wish to participate in the Balancing Mechanism (i.e. you wish to submit Physical Notifications (PNs) to the NETSO) you must contact the NETSO¹, to discuss any obligations and sign the necessary contractual agreements.

The BSC Primary BM Unit registration is separate to the NETSO BM Unit registration; however the Effective From Date for your BSC Primary BM Unit will need to be agreed with the NETSO.

When you contact the NETSO BM Unit registration team, the NETSO will provide you with the NGC BM Unit Id. Where you provide an NGC BM Unit Id and where the Final Physical Notification Flag (FPN) = Y, the CRA will ask the NETSO for approval of the registration and intended Effective From Date.

The Grid Code requires that Primary BM Units submit Physical Notifications (PNs) to the NETSO if their Generation or Demand Capacity is at or above 50MW in England and Wales, 30MW in South Scotland or 10MW in North Scotland. It is optional below these limits. Interconnector Primary BM Units always submit PNs. Secondary BM Units normally submit PNs.

Please note that if the NGC BM Unit requires new Electronic Data Transfer (EDT) and Electronic Dispatch Logging (EDL) to be installed there can be significantly longer lead times to install these than the BSC Primary BM Unit registration process. You should therefore aim to start your NCG BM Unit registration well in advance of your connection date to ensure that the timescales for your BSC Primary BM Unit registration are not impacted.

Types of BM Units

There are several types of BM Unit, each representing different aspects of the system. Each type is marked with prefixes in their IDs, as given below. Each type is described separately in the following sections, along with an overview of the registration process and what you need to do.

If you are only interested in a particular type of BM Unit, refer to the relevant section. The list below describes each type:

BM Unit Type	Prefix	Overview
Directly Connected	T_	Primary BM Units directly connected to the Transmission System.
Embedded	E_	Primary BM Units embedded within a / connected to a Distribution System.
Interconnector	I_	Primary BM Units related to an Interconnector.
Supplier	2_	Primary BM Units covering Supply. These contain all of a particular Supplier’s Meters for a given Grid Supply Point (GSP) Group in either a Base or Additional Supplier Primary BM Unit.
Supplier	C_	These Additional Supplier Primary BM Units are registered solely for the purpose of allocating Contracts for Difference (CfD) Assets.
Secondary	V_	Secondary BM Units may be registered by a VLP or AMVLP to provide Balancing Services to the NETSO.
Miscellaneous	M_	Other types of Primary BM Units that don’t fit the above categories. This prefix does not apply to newly registered Primary BM Units.

Primary BM Units submit Physical Notifications (PNs) to the NETSO if their Generation or Demand Capacity is at or above 50MW in England and Wales, 30MW in South Scotland or 10MW in North Scotland. It is optional below these limits. Interconnector Primary BM Units always submit PNs.

Directly Connected Primary BM Units

What is a Directly Connected Primary BM Unit?	Directly Connected Primary BM Units comprise of equipment directly connected to the Transmission System. They are usually Generation Units, relating to Power Stations or other Generating sites (e.g. wind farms) but can also be large demand sites. The equipment within each Primary BM Unit is independently controlled, and is metered separately.
Do I need to do anything before registering one?	You normally need to Qualify as a Generator to register Generation Directly Connected Primary BM Units or as a Supplier to register Demand Primary BM Units. If the Primary BM Unit will be Exempt Export (see below for more details), you may also register the Primary BM Unit if you are a Qualified Supplier. Visit the Market Entry page or BSCP65: Registration of Parties and Exit Procedures for more details. Before you submit the Primary BM Unit registration form you must contact the NETSO , to discuss any obligations and sign the necessary contractual agreements. The NETSO² will give you a NGC BM Unit Id.
What forms do I need to fill in (where the Elexon Kinnect Customer Solution is NOT used)?	BSCP15/4.1 gives general details of the Primary BM Unit(s) you’re registering. You must send the BSCP15/4.1 form to the Central Registration Agent³ (CRA) at least 30 Working Days (standard Primary BM Unit) or at least 60 Working Days (non-standard Primary BM Unit) before the Effective From Date (EFD). A BM Unit can also be registered on the Self-Service Gateway (Elexon Kinnect Customer Solution). BSCP15/4.13 requests a non-standard Primary BM Unit configuration. If your Primary BM Unit is non-standard, this must be submitted in addition to the BSCP15/4.1 form or the BM Unit can also be registered on the Self Service Gateway (Elexon Kinnect Customer Solution). BSCP20/4.1 ⁴ registers the Metering Systems related to your Primary BM Unit(s) and must be sent to the CRA² at least 20 Working Days before the EFD. BSCP20/4.3 registers the Meter Technical Details (MTDs) related to the Metering Systems of your Primary BM Unit(s), and is usually submitted by the Meter Operator Agent (MOA) to the CDCA2 at least 16 Working Days before the EFD. It can also be submitted by the Registrant of the Metering System. BSCP75/4.2 details the Aggregation Rules for the Primary BM Unit(s) and must be sent to the CDCA at least 20 Working Days before the EFD⁵ . BSCP02 details the Proving Test that your MOA must carry out on the Metering System. This must be completed at least 8 Working Days before the EFD. You must provide an electrical single line diagram of the site showing: the location of the Metering Equipment, in particular the Settlement current and voltage transformers (CTs/VTs) and CT/VT ratios; any existing Boundary Points and/ or any System Connection Points at or near the proposed Boundary Point(s); and any back up SVA connection and interlocking arrangements.
What information do I provide on the BSCP15/4.1 form (where the Elexon Kinnect Customer Solution is NOT used)?	The NGC BM Unit ID is the ID provided by the NETSO (where the Final Physical Notification (FPN) flag is Y). The Primary BM Unit ID has a prefix of ‘T_’ followed by the NGC BM Unit ID. The Primary BM Unit Type is ‘T’ for Directly Connected and the Primary BM Unit Configuration depends on what type of Unit it is – please check the list at the bottom of the form. You need to enter the Generation Capacity (GC) and Demand Capacity (DC) of each Primary BM Unit, as well as the Final Physical Notification (FPN) Flag. If you are using the Self-Service Gateway (Elexon Kinnect Customer Solution) you will need to enter the Maximum Positive QMij, and Maximum Negative QMij which will be doubled in the system to give the GC and the DC. If the Primary BM Unit will be Exempt Export (see below for more details), you must put ‘Y’ in the relevant column, and complete a BSCP15/4.5 form. The Exempt Export information can also be registered on the Self-Service Gateway (Elexon Kinnect Customer Solution). Finally, you need to state the proposed date on which the Primary BM Unit will become effective. Further guidance on completing this form is given in the ‘completing the BSCP15/4.1’ section below.
What other information is needed?	If you register the Primary BM Unit(s) as Exempt Export, refer to the Exempt Export section which covers additional processes that you need to follow.
When do I need to submit this information by?	You need to start the process at least 30 Working Days before your proposed Effective From Date if your Primary BM Unit is standard or at least 60 Working Days before your Effective From Date if your Primary BM Unit is non-standard. Forms can be submitted in any order, providing you meet the timescales above. Alternatively, this information (apart from the BSCP15/4.13 form) can be completed via the Self-Service Gateway (Elexon Kinnect Customer Solution).

For Generation Primary BM Units, more detail on registration and guidance on the market entry process can be found in the guidance BM Units – How to register Primary BM Units relating to Generating Plant in the Central Volume Allocation Market.

Embedded Primary BM Units

What is an Embedded Primary BM Unit?	Embedded Primary BM Units comprise of equipment that is connected to a Distribution Network. They are Generation Units relating to Power Stations or other generating sites (e.g. wind farms). They can include the imports relating to these sites, but large embedded demand sites without any generation cannot be registered as a Central Volume Allocation (CVA) Primary BM Unit. The equipment within each Primary BM Unit is independent of other Units, and is metered separately.
Do I need to do anything before registering one?	You need to Qualify as a Generator to register Embedded Primary BM Units. If the Primary BM Unit will be Exempt Export (see below for more details), you may also Qualify as a Supplier to register the Primary BM Unit or elect another Generator or Supplier Party to register the Primary BM Units. Visit the Market Entry page or BSCP65: Registration of Parties and Exit Procedures for more details. Before you submit the Primary BM Unit registration form, and if you wish to participate in the Balancing Mechanism (i.e. (FPN) Flag is set to Yes) you must contact the NETSO⁶ , to discuss any obligations and sign the necessary contractual agreements. The NETSO will give you NGC BM Unit Id(s).
What forms do I need to fill in (where the Elexon Kinnect Customer Solution is NOT used)?	BSCP15/4.1 gives general details of the Primary BM Unit(s) you’re registering. You must send the BSCP15/4.1 form to the Central Registration Agent⁷ (CRA) at least 30 Working Days (standard Primary BM Unit) or at least 60 Working Days (non-standard Primary BM Unit) before the Effective From Date (EFD). BM Units can also be registered on the Self-Service Gateway (Elexon Kinnect Customer Solution). BSCP15/4.13 requests a non-standard Primary BM Unit configuration. BM Units can also be registered on the Self-Service Gateway (Elexon Kinnect Customer Solution). BSCP20/4.1 ⁸ registers the Metering Systems related to your Primary BM Unit(s) and must be sent to the CRA²at least 20 Working Days before the EFD. BSCP20/4.3 registers the Meter Technical Details (MTDs) related to the Metering Systems of your Primary BM Unit(s), and is usually submitted by the Meter Operator Agent (MOA) to the CDCA² at least 16 Working Days before the EFD. It can also be submitted by the Registrant of the Metering System. BSCP75/4.2 details the Aggregation Rules for the Primary BM Unit(s) which must include reference to CVA Line Loss Factors and must be sent to the CDCA at least 20 Working Days before the EFD⁹ . BSCP02 details the Proving Test that your MOA must carry out on the Metering System. This must be completed at least 8 Working Days before the EFD. You must provide an electrical single line diagram of the site showing: the location of the Metering Equipment, in particular the Settlement current and voltage transformers (CTs/VTs) and CT/VT ratios; any existing Boundary Points and/ or any System Connection Points at or near the proposed Boundary Point(s); and any back up SVA connection and interlocking arrangements.
What information do I provide on the BSCP15/4.1 form (where the Elexon Kinnect Customer Solution is NOT used)?	The NGC BM Unit ID is provided by the NETSO (where FPN flag is Y). The Primary BM Unit ID has a prefix of ‘E_’ followed by the NGC BM Unit ID. The Primary BM Unit Type is ‘E’ for Embedded. The Primary BM Unit Configuration depends on what type of Unit it is - please check the list at the bottom of the form. You need to enter the GC and DC of each Primary BM Unit, as well as the FPN Flag, and the GSP Group ID in which the Primary BM Unit is located. If you are using the Self-Service Gateway (Elexon Kinnect Customer Solution) you will need to enter the Maximum Positive QMij, and Maximum Negative QMij which will be doubled in the system to give the GC and the DC. If the Primary BM Unit will be Exempt Export (see below for more details), you must put ‘Y’ in the relevant column, and complete a BSCP15/4.5 form. The Exempt Export information can also be registered on the Self-Service Gateway (Elexon Kinnect Customer Solution). Finally, you need to state the proposed date on which the Primary BM Unit will become effective. Further guidance on completing this form is given in the ‘completing the BSCP15/4.1’ section below.
What other information is needed?	Embedded Primary BM Units need CVA Line Loss Factors (LLFs) for use in their Aggregation Rules. The relevant Licensed Distribution System Operator (LDSO) is responsible for submitting them within the LLF timescales in BSCP128: Production, Submission, Audit and Approval of Line Loss Factors. Please ask the LDSO to submit CVA LLFs (as opposed to SVA LLFs) for the site and to cancel any SVA MPANs that they may have created for the site. If you register the Primary BM Unit(s) as Exempt Export, refer to the Exempt Export section, which covers additional processes that you need to follow.
When do I need to submit this information by?	You need to start the process at least 30 Working Days before your proposed Effective From Date if your Primary BM Unit is standard or at least 60 Working Days before your Effective From Date if your Primary BM Unit is non-standard. Forms can be submitted in any order, providing you meet the timescales above. Alternatively, this information (apart from the BSCP15/4.13 form) can be completed via the Self-Service Gateway (Elexon Kinnect Customer Solution).

Exempt Export Primary BM Units

Some Generating Plants are ‘Exemptable’, which means that the Lead Party doesn’t need a Generation Licence to operate the Plant. Some Generating Plants may be Class Exemptable, as set out in the Statutory Instruments exempting them from the requirement to hold a Generation Licence. Other Generating Plant may be Exemptable if granted an Individual Exemption by the Secretary of State. If you are unsure if your activity is licensable or Exemptable please contact the Ofgem Licensing team at licensing@ofgem.gov.uk.

The Lead Party of a Central Volume Allocation (CVA) Exemptable Generating Plant or the Supplier of a Supplier Volume Allocation (SVA) Exemptable Generating Plant can apply for the BM Unit containing the Exemptable Generating Plant to be granted exempt export status under the BSC. This means that the Lead Party or Supplier can receive Embedded Benefits¹⁰(if embedded) and choose the BM Unit P/C flag (if embedded or directly connected).

Note that an Exemptable Generating Plant does not have to be included in an Exempt Export Primary BM Unit under the BSC; however exemptable benefits can only be applied to Exempt Export Primary BM Units.

Standard and Non-Standard Primary BM Unit Configuration

The BSC requires that a Primary BM Unit must satisfy the following criteria (Section K3.1.2);

only one Party is responsible for the Exports and/or Imports from or to the Plant and/or Apparatus registered in Central Meter Registration Service (CMRS) (another Party may be responsible for an Supplier Meter Registration Service (SMRS) registered connection as in point (d));
the Exports and/or Imports relating to the Primary BM Unit are capable of being controlled independently of any other Exports and/or Imports which do not relate to the Primary BM Unit;
the Metered Volumes from the Primary BM Units Plant and Apparatus are submitted separately from any Plant and Apparatus not part of the Primary BM Unit
the Primary BM Unit does not contain Plant and/or Apparatus whose Imports and Exports are measured by both CVA and SVA Metering Systems except where:

0.0.1 1 the Registered Capacity of the Boundary Point measured by the Metering System(s) registered in SMRS is equal to or less than the limit determined by the Panel, currently 415V;

2. the Plant and Apparatus cannot Export through the Metering System registered in SMRS; and

3. there are measures in place to prevent instantaneous flow through of electricity:

from the Metering System registered in CMRS to the Metering System registered in SMRS; and/or
between different Systems such as the Transmission System and the Distribution System or between different Distribution Systems;

i.e. a backup connection to the Distribution System with registered capacity of less than 415V and with Metering systems registered in SMRS is allowed; and

Plant and Apparatus with a Registered Capacity of less than or equal to the size of a Small Power Station may be aggregated up to the size of a Small Power Station¹¹ (size applicable to both Imports and Exports) within a single Primary BM Unit. A Primary BM Unit comprised of Plant and Apparatus with a Registered Capacity of greater than the size of a Small Power station must be the smallest aggregation of the Plant and Apparatus for which the requirements mentioned in (a) to (c) would be met.

In addition to Primary BM Units meeting the criteria above, the BSC states a number of exceptions that are also considered to be a single Primary BM Unit (Section K3.1.4). These are included in the list Permissible Configurations of Plant and Apparatus on page on page 9 below;

Any configuration that does not meet the criteria above or is not on the list of single Primary BM Units in the BSC could be registered as a Nnon-Sstandard Primary BM Unit. The configuration of Non-Sstandard Primary BM Units need to be approved by the Imbalance Settlement Group (ISG) and this results in a 60 Working Day lead time.

If you need to apply for a Nnon-Sstandard Primary BM Unit, you will need to complete and submit a BSCP15/4.13 form accompanied by electrical single line diagrams to Elexon explaining why you believe that the Nnon-Sstandard configuration is more appropriate than a standard one. Alternatively, the electrical single line diagrams can be submitted via the Self-Service Gateway (Elexon Kinnect Customer Solution) as part of the BM Unit registration. All Nnon-Sstandard Primary BM Units are different so please contact the Elexon Participant Management team prior to applying for a Nnon-Sstandard Primary BM Unit as we can provide advice on the appropriateness of your proposals, the timescales and the requirements of your application form. As a minimum, your form should contain:

A description of the Plant and Apparatus, where it connects to the Total System and the location of the Metering Equipment with reference to the electrical single line diagram; and
The Plant and Apparatus that is to be included in each of the Nnon-Sstandard Primary BM Unit(s) and any other Sstandard Primary BM Units at the boundary point(s) with reference to the electrical single line diagram; and
The clause(s) of BSC Section K 3.1.2 that the Nnon-Sstandard Primary BM Unit does not satisfy and why; and / or
The benefits of the Nnon-Sstandard Primary BM Unit configuration compared to a different configuration and / or the limitations of a different configuration; and / or
Any relevant costs associated with the Nnon-Sstandard Primary BM Unit configuration (as opposed to a Sstandard Primary BM Unit configuration if appropriate), e.g. metering costs, BSC Costs.

The BSCP15/4.13 form is sent by Elexon to the NETSO for comment and to the ISG for decision. If the form is sent in Microsoft Word, we will remove the contact and authorised signatory information before sending it on. If the form is sent in PDF, please could you also send a copy without contact and authorised signatory information.

Please also note that as the diagrams need to be provided to ISG, the file size of an email containing diagrams should be kept below 4MB by compressing files or splitting into several files if necessary.

You can request that your application is considered in the confidential session of the ISG meeting, however the ISG encourages applications to be heard in the open session. If parts of your application are confidential, we can provide those parts to the ISG on a confidential basis (e.g. electrical single line diagrams). If you wish your whole application to be heard in the confidential session, the ISG asks that you provide the justification for this as part of your application.

Non-Sstandard Primary BM Units are presented to the ISG for decision taking into account the views of the NETSO. The ISG consider all applications on their individual merit. There is no guarantee that a Nnon-Sstandard configuration will be accepted, even if a similar configuration has previously been agreed. Any Party considering a configuration of Plant and Apparatus that may not be registered as a single Primary BM Unit is encouraged to consult the NETSO and seek approval for a Nnon-Sstandard Primary BM Unit from the ISG early in the design of the Plant and Apparatus.

The same Plant and Apparatus cannot be contained in more than one Primary BM Unit except in the following scenarios:

where different Parties are responsible for the Import to and Export from the same Plant and Apparatus. In this scenario each Party must register a Primary BM Unit, one for the Import and one for the Export;
where all or part of the Import to the Plant and Apparatus is metered by Metering Systems registered in both CMRS and SMRS. This may be a single Metering System registered in both SMRS and CMRS at a single Boundary Point or separate Metering Systems at separate Boundary Points. The Primary BM Units may be registered by the same or different Parties; or
Power Park Modules which belong to a Switching Group.

Where a Party is responsible for both the Imports to and the Exports from Plant and Apparatus, it cannot register separate Primary BM Units for the Import to and Export from the same Plant and Apparatus measured by the same Metering System.

Permissible Configurations of Plant and Apparatus

The following configurations of Plant and Apparatus are permissible in the BSC as single Primary BM Units. This list is not exhaustive. Other configurations of Plant and Apparatus would be permissible as single Primary BM Units if the configuration meets all the criteria for a Standard Primary BM Unit set out above:

Generating Unit (including Single Generating Unit Open Cycle Gas Turbine);
Closed Cycle Generating Turbine (CCGT) Module;
Power Park Module (PPM);
Power Station Transformers (Station Transformers)
Directly Connected Demand at a single Boundary Point Combined Offshore BM Unit (COBMU) ;
Directly connected Demand at more than one Boundary Point provided that the total Imports are equal to or less than 50MW in England and Wales, 30MW in South Scotland and 10MW in North Scotland;
Supplier (Base or Additional) Primary BM Unit;
Interconnector Primary BM Unit
Any BM Units that were determined as part of the transitional arrangements for the implementation of the British Electricity Trading and Transmission Arrangements (BETTA)
An Offshore PPM or COBMU¹² and its associated Low Voltage Assets
Combination of Generating Units connected to the Total system provided that the total Exports are equal to or less than 50MW in England and Wales, 30MW in South Scotland and 10MW in North Scotland
Electricity Storage Module provided that the total Exports are equal to or less than 50MW in England and Wales, 30MW in South Scotland and 10MW in North Scotland
Hybrid Plant – PPM ore.g. combination of Generating Units plus Storage Module PPM provided that the total Exports are equal to or less than 50MW in England and Wales, 30MW in South Scotland and 10MW in North Scotland

In addition, if there are different Parties responsible for the Import to or Export from one of the above configurations of Primary BM Units, the Import to the Plant and Apparatus can be registered in one Primary BM Unit and the Exports from the Plant and Apparatus in another Primary BM Unit as a standard configuration.

Any of the above configurations of Plant and Apparatus with associated Metering Systems registered in CMRS may have back up assets with Metering Systems registered in SMRS provided that the Registered Capacity of the Boundary Point with Metering systems registered in SMRS is less than or equal to 415V.

Configurations of Plant and Apparatus not Permissible (unless agreed by the ISG)

Any configuration of Plant and Apparatus either not on the list of permissible configurations above or not meeting the criteria for a Sstandard Primary BM Unit is not automatically permissible as a single Primary BM Unit in the BSC. Parties may apply for a Non-Standard Primary BM Unit for any configuration of Plant and Apparatus that cannot be registered as a single Primary BM Unit, including those below.

Open Cycle Gas Turbines with two or more generating Units (OCGTs) (including CCGT conversions);
Two or more onshore PPMs controlled as a single entity;
Combination of Generating Units or Electricity Storage ModulePPMs or hybrid Plant (generation plus storage) connected to the Total System, with total Exports greater than 50MW in England and Wales, 30MW in South Scotland and 10MW in North Scotland;
Directly Connected Premises at more than one Boundary Point with total Imports greater than 50MW in England and Wales, 30MW in South Scotland and 10MW in North Scotland;
Back-up assets for a CVA Primary BM Unit registered in SVA of more than 415V.
Registration of Directly Connected and Embedded Primary BM Units

What is a Directly Connected Primary BM Unit?

Directly Connected Primary BM Units comprise of equipment directly connected to the Transmission System with a Bilateral Connection Agreement (BCA) with the NETSO. They are usually Generation Units but can also be large demand sites.

What is an Embedded Primary BM Unit?

Embedded Primary BM Units comprise of equipment registered in CVA that is connected to a Distribution Network. They are Generation Units and can include the imports relating to these sites, but large embedded demand sites without any generation cannot be registered as a CVA Embedded Primary BM Unit.

Assets that have a Bilateral Embedded Generation Agreement (BEGA), with the NETSO normally must be registered in the BSC as CVA Primary BM Unit(s) as a condition of the BEGA.

How long does it take to register a Directly Connected or Embedded BM Unit?

The registration of a Standard BM Unit has a 30 Working Day lead time and a Non-Standard BM Unit has a 60 Working Day lead time within BSC Systems. We therefore recommend that you start the process about three to four months before your earliest energisation date.

How do I register a Directly Connected or Embedded BM Unit?

During Market Entry:

To register the BM Unit please log into the Elexon Kinnect Customer solution:. You can complete and submit the information in Kinnect if you are a Category A signatory or complete the information as an Assistant and send it to a Category A signatory to submit. For information on accessing Kinnect, please refer to: <FAQ>

Click on myRegister Aassets and you will be directed to the manage assets page
Click on Manage Assets
Click on the plus button on the right hand side to add a new asset
Click on Balancing Mechanism Unit
Complete the mandatory starred fields:

BM Unit Id is of the form T_[NGC BM Unit Id] for directly connected BM Units or E_[NGC BM Unit Id] for embedded BM Units. If you do not have an NGC BM Unit Id, please create an ID that is relevant to your site (maximum character length 11 including T_ or E_).
The FPN Flag will be ‘Yes’ if you are trading in the Balancing Mechanism and have a NGC BM Unit ID. Otherwise it is no.
The Effective From Date should be at least 30 Working Days in the future for Standard BM Units or 60 Working Days in the future for Non-Standard BM Units.
You need to enter the Generation Capacity (GC) and Demand Capacity (DC) of each Primary BM Unit, as well as the Final Physical Notification (FPN) Flag. You need to enter the GC and DC as the Maximum Positive QMij, and Maximum Negative QMij which will be doubled in the system to give the GC and the DC.
If the Primary BM Unit will be Exempt Export, select Exempt Export and explain why it is exempt Export. Also select the BM Unit Production / Consumption Flag. Note that this field will appear under the BM Unit Type field when you select Exempt Export and you will need to scroll up the page to complete it.

You must upload an electrical single line diagram of the site showing:

the location of the Metering Equipment, in particular the Settlement current and voltage transformers (CTs/VTs) and CT/VT ratios;
any existing Boundary Points and/ or any System Connection Points at or near the proposed Boundary Point(s); and
any back up SVA connection and interlocking arrangements.

If you have indicated that the BM Unit configuration is Non-Standard, please complete form BSCP15/4.13 to explain why you believe that the BM Unit should be registered as a Non-Standard BM Unit.

If you are unable to complete the BM Unit application through Kinnect, please complete this information in form BSCP15/4.1 and submit it to bm.unit@elexon.co.uk and neta@imserv.com. If the BM Unit is Exempt Export please also complete form BSCP15/4.5A.

After Market Entry

If you need to register more BMUs after Market Entry then the process is similar to the above, except that you will need to click on the ‘My Assets’ tile from the home page and then click on the ‘Manage Assets’ tile to view your existing BMUs and create new ones.

If you are unable to complete the BM Unit application through the Elexon Kinnect Customer solutionKinnect, please complete this information in form BSCP15/4.1 and submit it via Elexon Support: https://support.elexon.co.uk/csm.to bm.unit@elexon.co.uk and neta@imserv.com. If the BM Unit is Exempt Export please also complete form BSCP15/4.5A.

What else is needed before the BM Unit can go live?

BSCP20/4.1^¹³^: This form details the CVA Metering System Identifier (MSID) being registered for the Primary BM Unit, and the CVA Meter Operator (CVA MOA) appointed by you^¹⁴. You can reserve a CVA MSID for the site in advance by emailing the CRA (neta@imserv.com), stating the Name, whether it is Transmission or Distribution connected, and its location (England and Wales, North of Scotland, or South of Scotland). The CRA will provide details of the CVA MSID. For a Distribution connected Metering System, the LDSO may determine that a separate Line Loss Factor (LLF) is required to be applied to the Export and the Import flows; in this case, two CVA MSIDs would be required. The BSCP20/4.1 forms need to be sent by the Registrant to the CRA (neta@imserv.com) by 20 WD prior to the EFD.

BSCP75/4.2^¹⁵: This form details the Aggregation Rules for the Primary BM Unit(s). For an embedded Primary BM Unit, then the rule will also need to include reference to a LLF. Guidance on writing Aggregation Rules can be found in the Aggregation Rules Guidance. Note that the identifiers in the Aggregation Rules need to match those in the Meter Technical Details. The BCP75/4.2 form needs to be sent by the Registrant to the CRA (neta@imserv.com) by 20 WD prior to the EFD.

Metering Equipment should be compliant with the relevant Code of Practice at the time of first registration for Settlement purposes, however should any aspect of your Metering System be unavoidably non-compliant, there is a process for making an application for a Metering Dispensation from the relevant Code of Practice via BSCP32 ¹⁶ . Elexon can advise prior to submission and we recommend that the signed BSCP32/4.1 form and any supporting documentation is submitted at least 14 weeks prior to the EFD. Metering Dispensations should be sent to dispensations@elexon.co.uk. Note that Panel Committees may approve, reject or defer a decision on a Metering Dispensation so the ideal situation is for all metering to be compliant with the relevant Code of Practice. Further information on the Metering Dispensation process can be found on the Metering Dispensations page of the BSC Website.

BSCP20/4.3 registers the Meter Technical Details (MTDs) related to the Metering Systems of your Primary BM Unit(s), and is usually submitted by the Meter Operator Agent (MOA) to the CDCA² (neta@imserv.com) at least 16 Working Days before the EFD. It can also be submitted by the Registrant of the Metering System.

Your CVA MOA must Commission and Prove the Metering System in accordance with Code of Practice 4¹⁷ and BSCP02 ¹⁸ . This must be completed at least 8 Working Days before the EFD.

BSCP25/5.1 ¹⁹ is required for Directly Connected BM Units and registers the Transmission System Boundary Point. It is submitted by the NETSO. Elexon will liaise with the NETSO for the submission of this information.

Embedded Primary BM Units need CVA LLFs for use in their Aggregation Rules. The relevant Licensed Distribution System Operator (LDSO) is responsible for submitting them within the LLF timescales in BSCP128²⁰. Please ask the LDSO to submit CVA LLFs (as opposed to SVA LLFs) for the site and to cancel any SVA MPANs for the Distribution connection that they may have allocated, as the CVA MSID will be used instead.

For an embedded (distribution connected) Primary BM Unit, the relevant LDSO will need to update the relevant GSP Group Take Aggregation Rules. These are prepared by the Central Data Collection Agent (CDCA) and signed off by the LDSO. Elexon will manage this process as GSP Group Take Aggregation Rules need to be updated in the order that assets are added to or removed from a GSP Group.

Switching Groups

Some Offshore and onshore Power Park Modules (PPM) can be moved between Primary BM Units. You can set the relevant Primary BM Units up in a Switching Group, and opt to run the relevant PPM in any of the Primary BM Units within that Switching Group. To set this up, you must enter the relevant details in the Elexon Kinnect Customer solution or in the table at the end of the BSCP15/4.1 form as well as submitting the applicable Aggregation Rules (BSCP75) for all the possible running configurations when you are registering the Aggregation Rules.

Approval to Energise

When all the above steps have been completed and checked by Elexon, Elexon will issue an approval to energise the Transmission System Boundary Point to the NETSO (for directly connected Primary BM Units), or an approval to energise the Primary BM Unit connection to the relevant LDSO (for Embedded Primary BM Units). This will be for the date you requested or a later date if that is not achievable. Please keep Elexon informed of changes to your intended energisation date.

All registration requirements should be completed in time to allow the approval to energise email to be issued at least 4 WD before your Effective From Date.

The Effective From Date given in the approval to energise email is the earliest date that you can physically energise your connection to the Transmission / Distribution System and this is the date that the CDCA will begin to collect Metered Data from your site. It does not matter if the physical energisation date of your equipment is after the Effective From Date quoted in the approval to energise email, but it must not be before.

Registration of Interconnector Primary BM Units

What is an Interconnector Primary BM Unit?

Interconnector Primary BM Units allow Parties to trade over a particular Interconnector, and always come in pairs. One of the Primary BM Units is for electricity entering the System over the Interconnector (Production), and the other is for electricity being taken off the System (Consumption). Each Interconnector has many pairs of these Primary BM Units, one pair for each Party who has registered to use it.

Interconnector Primary BM Units work differently to other Primary BM Units because the electricity is not metered for each Party’s Primary BM Units, but at the Interconnector Boundary. The Interconnector Administrator submits the deemed Primary BM Unit Metered Volume on the Party’s behalf. The difference between the Interconnector Metered Volume and the Primary BM Unit Metered Volumes (deemed to have been delivered) is attributed to the Interconnector Error Administrator. For more information about Interconnectors please refer to the Interconnector Trading Guidance.

How do I register an Interconnector BM Unit?

During Market Entry:

To register the BM Unit please log into the Elexon Kinnect Customer solution:

Click on Register Assets and you will be directed to the manage assets page
To register the BM Unit please log into the Elexon Kinnect Customer solution. You can complete and submit the information in Kinnect if you are a Category A signatory or complete the information as an Assistant and send it to a Category A signatory to submit. For information on accessing Kinnect, please refer to: <FAQ>
Click on my assets
Click on Manage Assets
Click on the plus button on the right hand side to add a new asset
Click on Balancing Mechanism Unit
Complete the mandatory starred fields:

BM Unit Id is of the form I_[NGC BM Unit Id]
The FPN Flag will be ‘Yes’
The Effective From Date should be at least 30 Working Days in the future.
Choose the Interconnector that the BM Unit relates to.
For the Production Primary BM Unit (i.e. electricity flowing into the GB Transmission System), enter a Maximum Positive QMij, a zero in the Maximum Negative QMij DC and a ‘P’ for Production/Consumption (P/C) Flag. The Maximum Positive QMij will be doubled in the system to give the GC.

You will need to go through the same steps to add the other asset in the BM Unit pair.

For the Consumption Primary BM Unit (i.e. electricity flowing from the GB Transmission System), enter a zero in the Maximum Positive QMij, a Maximum Negative QMij and a ‘C’ for the Flag. The Maximum Negative QMij will be doubled in the system to give the DC.

After Market Entry

If you are unable to complete the BM Unit application through the Elexon Kinnect Customer solution, please complete this information in form BSCP15/4.1 and submit it via Elexon Support: https://support.elexon.co.uk/csm.

What is an Interconnector Primary BM Unit?	Interconnector Primary BM Units allow Parties to trade over a particular Interconnector, and always come in pairs. One of the Primary BM Units is for electricity entering the System over the Interconnector (Production), and the other is for electricity being taken off the System (Consumption). Each Interconnector has many pairs of these Primary BM Units, one pair for each Party who has registered to use it. Interconnector Primary BM Units work differently to other Primary BM Units because the electricity is not metered for each Party’s Primary BM Units, but at the Interconnector Boundary. The Interconnector Administrator submits the deemed Primary BM Unit Metered Volume on the Party’s behalf. The difference between the Interconnector Metered Volume and the Primary BM Unit Metered Volumes (deemed to have been delivered) is attributed to the Interconnector Error Administrator. For more information about Interconnectors please refer to Interconnector Trading.
Do I need to do anything before registering one?	You need to Qualify as an Interconnector User to register Interconnector Primary BM Units. Visit the Market Entry page or BSCP65: Registration of Parties and Exit Procedures for more details. Before submitting the Primary BM Unit registration form, you must contact the NETSO²¹ , to discuss your obligations and sign the necessary contractual agreements. The NETSO will give you NGC BM Unit names.
What forms do I need to fill in (where the Elexon Kinnect Customer Solution is NOT used)?	BSCP15/4.1 gives general details of the Primary BM Unit(s) you’re registering. This must be sent to the CRA 30 Working Days before the Effective From Date. BM Units can also be registered on the Self-Service Gateway (Elexon Kinnect Customer Solution).
What information do I provide on the BSCP15/4.1 form (where the Elexon Kinnect Customer Solution is NOT used)?	The NGC BM Unit ID is the ID provided by the NETSO. The Primary BM Unit ID has a prefix of ‘I_’ followed by the NGC BM Unit ID. The Primary BM Unit Type is ‘I’ for Interconnector, and the Primary BM Unit Configuration will be ‘IC’ for Interconnector Unit. For the Production Primary BM Unit (i.e. electricity flowing into the GB Transmission System), enter a positive GC, a zero DC and a ‘P’ for Production/Consumption (P/C) Flag. If you are using the Self-Service Gateway (Elexon Kinnect Customer Solution) you will need to enter the Maximum Positive QMij which will be doubled in the system to give the GC. For the Consumption Primary BM Unit (i.e. electricity flowing from the GB Transmission System), enter a zero GC, a negative DC and a ‘C’ for the Flag. If you are using the Self-Service Gateway (Elexon Kinnect Customer Solution) you will need to enter the Maximum Negative QMij which will be doubled in the system to give the DC. In both cases, the FPN Flag is ‘Y’. Finally, enter the Interconnector ID for the Interconnector these Units are for (i.e. FRANCE, MOYLE, BRITNED, EWIC, NEMOLINK, ELECLINK, IFA2), and the date that the Primary BM Units will be effective from. Further guidance on completing this form is given in the ‘completing the BSCP15/4.1’ section below.
When do I need to submit this information by?	You must submit the BSCP15/4.1 form at least 30 Working Days before your proposed Effective From Date.

Registration of Supplier Primary BM Units (2_Primary BM Units)

What is a Supplier Primary BM Unit?

Supplier Primary BM Units measure the amount of electricity supplied by Suppliers. Due to the high number of Supplier Meters that exist, individually identifying them all is unfeasible. Instead, all the Meters for a particular Supplier ID in a specific GSP Group are grouped into one Supplier Primary BM Unit.

When you sign up as a Supplier, you will be allocated 14 ‘Base’ Supply Primary BM Units, one for each GSP Group, even if you do not plan to use them all. All your supply and SVA registered embedded generation in a particular GSP Group will by default be allocated to the relevant Base Primary BM Unit.

You can register ‘Additional’ Primary BM Units for particular asset or grouping of Customers within a GSP Group.

How do I register Base Supplier BM Units?

As part of the Elexon Market Entry Process, you will need to register the Supplier Role, and your Market Participant Identifier (MPID) in both the Central Registration Agent (CRA) Database and the Market Domain Data (MDD) Database.

As part of the Elexon Market Entry Process, you will be given access to the Elexon Kinnect Customer solutionElexon Kinnect – Customer Solution. You will need to register the Supplier Role, by accessing the register market role tile and creating a new role of Supplier.

Your 14 Base Supplier Primary BM Units will be automatically created by the Customer Solution as part of becomingregistering your role of a Supplier.

For each of your Base BM Units, you then need to enter various BM Unit Details by clicking on the Manage Asset Details, then clicking on the ‘+’, and entering data items such as the Effective From Date and, the Generation Capacity (GC) and Demand Capacity (DC) of each Primary BM Unit. You need to enter this as the Maximum Positive QMij, and Maximum Negative QMij which will be doubled in the system to give the Generation Capacity (GC) and the Demand Capacity (DC).. You should have been given accesses to the Elexon Kinnect Customer solution as part of the Market Entry process.

In order to add the BM Unit details you will need to click on the register assets page within the home screen. This will take you to the manage assets page where you will see the 14 Base BMUs that have been created. You can then access each BMU and click on the manage asset details button which will take you to the form to complete (see screenshots below):

Click on each Asset ID:

Click on the manage asset details button in the bottom left:

Click on the plus button on the manage BM Unit details screen:

Complete the relevant information on the register asset detail page:

If you are unable to update the complete the Maximum Positive QMij, and Maximum Negative QMij through the Elexon Kinnect Customer solution, please complete this information in form BSCP15/4.1 and submit it via Elexon Support: https://support.elexon.co.uk/csm.

The Supplier Role, and your Market Participant Identifier (MPID) will need to be registered in both the Central Registration Agent (CRA) Database and the Market Domain Data (MDD) Database. The Customer Solution registers your role in CRA, but to

To register the Supplier details and the Base BM Units in the MDD Database, please complete MDD Change Request form F509/01 & Entity Forms 1, 45 & 61. Please Email these Forms to Mddc@elexon.co.uk. The usual EFD is the next available MDD Go live Date as per the MDD Release Schedule

How do I register an Additional Supplier BM Unit?

To register as an Additional BM Unit, you need to register it in the Central Registration Agent (CRA) Database and the Market Domain Data (MDD) Database. You cannot register an Additional BM Unit until you have registered your 14 Supplier Base BM Units.

To register the BM Unit in CRA please log into the Elexon Kinnect Customer solution. You can complete and submit the information in Kinnect if you are a category A signatory or complete the information as an Assistant and send it to a Category A signatory to submit. For information on accessing Kinnect, please refer to: <FAQ>:

Click on Mmy Aassets
Click on Manage Assets
Click on the plus button on the right hand side to add a new asset
Click on Balancing Mechanism Unit
Complete the mandatory starred fields:

BM Unit Id is of the form 2__XMPIDnnn, where _X is the GSP Group, MPID is your four letter MPID and nnn is the next available number for an Additional BM Unit registered to your MPID in the GSP Group, starting 001 or a number of your choosing.
The Effective From Date should be at least 15 Working Days in the future and on or after the Effective From Date of the BM Unit in Market Domain Data.
If you are participating in the Balancing Mechanism and have an NGC BM Unit Id, then set the FPN Flag to ‘yes’ and add the NCG BM Unit Id. Otherwise leave the FPN Flag as ‘No’
You need to enter the Generation Capacity (GC) and Demand Capacity (DC) of each Primary BM Unit, as well as the Final Physical Notification (FPN) Flag. You need to enter this as the Maximum Positive QMij, and Maximum Negative QMij which will be doubled in the system to give the GC and the DC.
Enter a Baseline status of ‘Yes’ if Settlement Expected Volumes should be used instead of PNs in the calculations or ‘No’ if the BM Unit does not submit PNs or PNs should be used in the calculations.
If the Additional Primary BM Unit will be Exempt Export, select Exempt Export and explain why it is exempt Export. Also select the BM Unit Production / Consumption Flag. Note that this field will appear under the BM Unit Type field when you select Exempt Export and you will need to scroll up the page to complete it.

Note that if a Primary Supplier BM Unit is registered as an Exempt Export BM Unit, it can only contain the Exemptable Generating Plant for which it is being registered, it cannot contain additional generation or demand. i.e. it must satisfy the conditions for a Standard Primary BM Unit or be approved by the Panel as a Non-Standard Primary BM Unit as set out in the section above, as if it were an embedded Primary BM Unit.

A Base Primary BM Unit can have an Exempt Export status, if it contains a single Exemptable Generating Plant. A Party that wishes to flag a Base Primary BM Unit as Exempt Export Status needs to ensure that they do not allocate any other Generation or Demand to that Primary BM Unit.

If you are unable to complete the application through the Elexon Kinnect Customer solution, please complete this information on pages 1 and 2 of form BSCP15/4.1 and submit it via Elexon Support: https://support.elexon.co.uk/csm. If the BM Unit is Exempt Export please also complete form BSCP15/4.9A.

To register the BM Unit in the MDD Database, please complete MDD Change Request form F509/01 & Entity Form 61. Please Email these Forms to Mddc@elexon.co.uk. The usual EFD is the next available MDD Go live Date as per the MDD Release Schedule

Is there anything else I need to do?

You need to allocate SVA MSIDs to the Additional BMU in your own systems. You also need to instruct your appointed HHDA to transfer the relevant SVA MSIDs out of the Base BM Unit into the Additional BM Unit by you as a Supplier sending a D0297 “Notification of BM Unit Allocation data flow to the appointed HHDA, in accordance with the process in section 3.5 of BSC Procedure BSCP503 (‘Half Hourly Data Aggregation for SVA Metering Systems registered in SMRS’). Your HHDA should confirm successful allocation by sending back a D0294 “Confirmation of BM Unit Allocation” Data flow.

If you wish to use an Additional Primary BM Unit for Balancing Services, you need to allocate SVA MSIDs to it using the process contained in BSCP602: SVA Metering System and Asset Metering System Register section 2.1. Further guidance is provided in ‘Wider Access Guidance For Virtual Lead Parties (VLPs), Asset Metering VLPs and Suppliers’

Are there any other options?

If you wish to register an Additional Primary BM Unit in every GSP Group you may wish to register an additional Market Participant Identifier (MPID) under your Trading Party Id instead²² . This would have the effect of creating another set of 14 Supplier Primary BM Units under the new MPID and which would carry no extra BSC Charges. Creating a set of 14 Additional BM Units, one in each GSP Group would cost £840²³ in BSC Charges (see the Schedule of Main and SVA Specified Charges). If registering an additional MPID you should consider the impact that splitting your portfolio may have on your reporting e.g. DTN, PARMs.

You will need to register the additional MPID in CRA and MDD. To register an additional MPID in CRA you can log into the Elexon Kinnect Customer solution and from the homepage click on the ‘My roles’ tile. Click on the plus button in the top right hand corner to register a new Supplier role with a new MPID.

Your 14 Base Supplier Primary BM Units for the new MPID will be automatically created by the Customer Solution as part of registering your role of Supplier.

For each of your Base BM Units, you then need to enter various BM Unit Details such as the Effective From Date and the Maximum Positive QMij, and Maximum Negative QMij which will be doubled in the system to give the Generation Capacity (GC) and the Demand Capacity (DC)..

Click on each Asset ID:

Click on the manage asset details button in the bottom left:

Click on the plus button on the manage BM Unit details screen:

Complete the relevant information on the register asset detail page:

need to submit form BSCP65/05. This will result in you being allocated 14 Base Supplier BM Units. You need to enter the Generation Capacity (GC) and Demand Capacity (DC) of each Primary BM Unit within the Elexon Kinnect Customer solution. You need to enter this as the Maximum Positive QMij, and Maximum Negative QMij which will be doubled in the system to give the GC and the DC. AlternaivelyAlternatively the Additional MPID can be registered using a BSCP65/05. Also, If you are unable to update the complete the Maximum Positive QMij, and Maximum Negative QMij through the Elexon Kinnect Customer solution, please complete this information in form BSCP15/4.1 and submit it via Elexon Support: https://support.elexon.co.uk/csm.

To register the additional MPID in the MDD Database, please complete MDD Change Request form F509/01 & Entity Forms 1, 45 & 61. Please Email these Forms to Mddc@elexon.co.uk. The usual EFD is the next available MDD Go live Date as per the MDD Release Schedule

The Process is described in BSCP65 Section 4.8 and BSCP15 Section 3.3.

Note that if you wish to participate in the Balancing Mechanism, the NETSO may require you to register Additional Supplier BM Units as opposed to registering an additional MPID with Base Supplier BM Unite

What is a Supplier Primary BM Unit?	Supplier Primary BM Units measure the amount of electricity supplied by Suppliers. Due to the high number of Supplier Meters that exist, individually identifying them all is unfeasible. Instead, all the Meters for a particular Supplier ID in a specific GSP Group are grouped into one Supplier Primary BM Unit. When a Party signs up as a Supplier, they must register 14 ‘Base’ Supply Primary BM Units, one for each GSP Group, even if they do not plan to use them all. All their supply and SVA registered embedded generation in a particular GSP Group will by default be allocated to the relevant Base Primary BM Unit. A Party can register ‘Additional’ Primary BM Units for particular sites, or grouping of Customers, within a GSP Group.
Do I need to do anything before registering one?	You need to Qualify as a Supplier to register Supplier Primary BM Units. Visit the Market Entry page or BSCP65: Registration of Parties and Exit Procedures for more details. Your Base Primary BM Units need to be registered as part of becoming a Supplier. Additional Units can be registered at the same time as Base Primary BM Units or any time after. The Effective Dates of Supplier Primary BM Units must be on or after the next eligible Market Domain Data (MDD) Go-Live Date. MDD Go-Live dates are published on the MDD Release Schedule. Before you submit the Primary BM Unit registration form, and if you wish to participate in the Balancing Mechanism (i.e. (FPN) Flag is set to Yes) you must contact the NETSO²⁴ , to discuss any obligations and sign the necessary contractual agreements. The NETSO will give you NGC BM Unit Id(s).
What forms do I need to fill in (where the Elexon Kinnect Customer Solution is NOT used)	BSCP509 F509/01 is the MDD Change request form and BSCP509 Appendix 1 form MDD Entity Id 61 gives the details of the Supplier, GSP Group and BM Unit Id mapping for inclusion in Market Domain Data (MDD). These must be sent to the MDD Coordinator²⁵ by the fast track CR deadline for the Version of MDD you want the changes to be included in. Please see the MDD Release Schedule for a list of these dates. BSCP15/4.1 gives general details of the Primary BM Unit(s) that you are registering. This must be sent to the CRA at least 15 Working Days before the Effective From Date which must be on or after the next eligible MDD Go-Live Date.
What information do I provide on the BSCP15/4.1 form (where the Elexon Kinnect Customer Solution is NOT used)?	The Base Primary BM Unit ID is 2__XPPPP000, where X is the relevant GSP Group letter, PPPP is your four-letter Supplier Market Participant Identifier (MPID), and 000 represents your Base Primary BM Unit. Additional Primary BM Units are numbered sequentially, i.e. 001, 002 etc, within each GSP Group. If you are submitting FPNs, the NETSO will provide you with the NGC BM Unit ID. The Primary BM Unit Type is ‘G’ if these are your Base Primary BM Units, and ‘S’ if you are registering Additional Primary BM Units. The Primary BM Unit Configuration is either ‘BB’ for a Base Unit or ‘AB’ for an Additional Unit. You need to enter the Generation and Demand Capacities (GC and DC) of each Primary BM Unit as well as the FPN Flag. You need to state the date on which the Primary BM Unit will be effective from (this must be on or after the next eligible MDD Go-Live Date). If you are using the Self-Service Gateway (Elexon Kinnect Customer Solution) you will need to enter the Maximum Positive QMij, and Maximum Negative QMij which will be doubled in the system to give the GC and the DC.
What other information is needed?	If you register the Primary BM Unit(s) as Exempt Export, refer to the Exempt Export section, which covers additional processes that you need to follow. Note that if a Supplier Primary BM Unit is registered as an Exempt Export BM Unit, it must satisfy the conditions for a standard Primary BM Unit or be approved by the Panel as a non-standard Primary BM Unit as set out in the section above, as if it were an embedded Primary BM Unit.
When do I need to submit this information by?	You must submit the BSCP15/4.1 form at least 15 Working Days before your proposed Effective From Date which must be on or after the next eligible MDD Go-Live Date. You must submit your MDD forms in line with the MDD Release Schedule. Alternatively, this information can be completed via the Self-Service Gateway (Elexon Kinnect Customer Solution).
Is there anything else I need to do?	If you register an Additional Primary BM Unit, you need to allocate SVA MSIDs to that Additional Primary BM Unit using the process contained in BSCP503: Half Hourly Data Aggregation for SVA Metering Systems Registered in SMRS section 3.5, otherwise these Primary BM Units will remain in the Base Supplier Primary BM Unit. If you wish to use an Additional Primary BM Unit for Balancing Services, you need to allocate SVA MSIDs to it using the process contained in BSCP602: SVA Metering System and Asset Metering System Register section 2.1
Are there any other options?	If you wish to register an Additional Primary BM Unit in every GSP Group you may wish to register an additional Market Participant Identifier (MPID) under your Trading Party Id instead²⁶ . This would have the effect of creating another set of 14 Supplier Primary BM Units under the new MPID and which would carry no extra BSC Charges. Creating a set of 14 Additional BM Units, one in each GSP Group would cost £840 in BSC Charges (see the Schedule of Main and SVA Specified Charges). If registering an additional MPID you should consider the impact that splitting your portfolio may have on your reporting e.g. DTN, PARMs. To register an additional MPID you need to submit forms BSCP65/05, BSCP15/4.1, BSCP509 F509/01 MDD Change request form and BSCP509 Appendix 1 form MDD Entity Ids 1, 45 and 61. The Process is described in BSCP65 Section 4.8 and BSCP15 Section 3.3

Registration of Supplier Additional Primary BM Units (C_ BM Units) for EMR Assets

Supplier Primary BM Units (C_Primary BM Units) for EMR

Suppliers can register Additional BM Units for Contract For Difference (CfD) Assets using the registration of Additional Supplier BM Units process described above. Please refer to the Guidance on the registration of Additional Supplier Primary BM Units for the purpose of allocating Contracts for Difference (CfD) Assets can be found in the Registration of Primary BM Units for EMR guidance for naming conventions.

Electricity Market Reform Settlement Limited (EMRS) will register a set of Supplier Additional BM Units for every interested Supplier when a new SVA registered CfD Assets is due to go live so that a Supplier has a BM Unit for the Asset should they obtain a contract for that Asset. As there are a large number of ‘Empty’ Additional Supplier BM Units for EMR Assets, there is no charge associated with these BM Units.

Registration of Secondary BM Units (V_BM Units)

Secondary BM Units (V_Secondary BM Units)

What is a Secondary BM Unit?

Secondary BM Units record the amount of Balancing Energy provided by VLPs or AMVLPs to the NETSO.

How do I register a Secondary BM Unit?

During Market Entry:

To register the BM Unit please log into the Elexon Kinnect Customer solution. You can complete and submit the information in Kinnect if you are a Category A signatory or complete the information as an Assistant and send it to a Category A signatory to submit. For information on accessing Kinnect, please refer to: <FAQ>

Click on Register Assets and you will be directed to the manage assets page
Click on my assets
Click on Manage Assets
Click on the plus button on the right hand side to add a new asset
Click on Balancing Mechanism Unit
Complete the mandatory starred fields:

BM Unit Id is of the form V__XPPPPNNN, where X is the relevant GSP Group letter, PPPP is your four-letter Identifier (this may be the same as your Market Participant Identifier (MPID) if you are also a Supplier) and NNN are numbered sequentially, i.e. 001, 002 etc, for your identifier within each GSP Group or a number of your choosing.
The FPN Flag will be ‘Yes’
The Effective From Date should be at least 15 Working Days in the future.
Enter a Production/Consumption (P/C) Flag of either P or C. This is only relevant for Parties who also have other Party roles under the BSC. If you are a VLP only, you must enter a C. If not sure, then enter a C.
Enter a Baseline status of ‘Yes’ if Settlement Expected Volumes should be used instead of PNs in the calculations or ‘No’ if the BM Unit does not submit PNs or PNs should be used in the calculations.

After Market Entry

If you are unable to complete the BM Unit application through the Elexon Kinnect Customer solution, please complete this information in form BSCP15/4.14 and submit it via Elexon Support: https://support.elexon.co.uk/csm.

Is there anything else I need to do?

MSID Registration

VLPs need to allocate their SVA Metering System Id (MSID) Pairs to their Secondary BM Units. They can do so via the Elexon Kinnect Customer Solution once the effective from date (this can be a future date) of their Secondary BMU has been agreed and set to successful in the system.

To bulk upload MSID Pairs please log into the Elexon Kinnect Customer Solution:

Click on My Assets
Click on Manage MSID Pairs
Click on download at the bottom of the screen to download a CSV template that you can populate with the MSIDs.
Once populated please save and upload via the same screen.

To register single MSID Pairs please log into the Elexon Kinnect Customer Solution (this process is not recommended and you should use the bulk upload functionality above):

Click on My Assets
Click on Manage MSID Pairs
Click on the plus button in the right hand corner of the screen.
You will be taken to the register asset page where you need to complete all the mandatory fields and click save and send for Elexon’s approval.
Once you have sent this you will be taken back to the manage MSIDs page.
You will then need to add the consent flag to complete the MSID Pair. In order to do this, click on the MSID Pair you have just registered and you will be taken to the amend MSID Pair screen. Scroll down to the middle of the page where you will see the consent flag. Click on the plus button on the right hand side and complete the consent information before saving the record.

Further information on this process can be found in the Wider Access Guidance For Virtual Lead Parties (VLPs), Asset Metering VLPs and Suppliers guidance.

AMSID Registration

using the processes contained in BSCP602.

AMVLPs need to register their Asset Metering Systems before allocating the Asset Metering System Id (AMSID) Pairs to their Secondary BM Units. They can do so via the Elexon Kinnect Customer Solution once the effective from date (this can be a future date) of their Secondary BMU has been agreed and set to successful in the system.

using the processes contained in BSCP602.

To register single AMSID Pairs please log into the Elexon Kinnect Customer Solution:

Click on My Assets
Click on Manage AMSID Pairs
Click on the plus button under the heading ‘create asset’ on the right hand side of the page
Complete all four stages of the AMSID registration (Register Asset, Register Asset Metering Agents, Register Asset Meters and Allocate AMSID Pair to Secondary BMU) by completing the mandatory fields and clicking save each time at the bottom right hand corner of the page.

To bulk upload AMSID Pairs please log into the Elexon Kinnect Customer Solution:

Click on My Assets
Click on Manage AMSID Pairs
To upload multiple AMSID Pairs click on the download link under the ‘create multiple assets’ heading and complete the information before saving and uploading the file from the same section.

If you are unable to complete the registration of MSID/AMSID Pairs on the Elexon Kinnect Customer Solution then please follow the manual process in the BSCP602. Further guidance is also provided in ‘Wider Access Guidance For Virtual Lead Parties (VLPs), Asset Metering VLPs and Suppliers’

What is a Secondary BM Unit?	Secondary BM Units record the amount of Balancing Energy provided by VLPs or AMVLPs to the NETSO.
Do I need to do anything before registering one?	You need to Qualify as a VLP or AMVLP to register Secondary BM Units. Visit the Market Entry page or BSCP65: Registration of Parties and Exit Procedures for more details. Before submitting the Secondary BM Unit registration form, you must contact the NETSO²⁷ , to discuss your obligations and sign the necessary contractual agreements. The NETSO will give you NGC BM Unit Id(s).
What forms do I need to fill in (where the Elexon Kinnect Customer Solution is NOT used)?	BSCP15/4.14 gives general details of the Secondary BM Unit(s) you are registering. This must be sent to the CRA at least 15 Working Days before the Effective From Date. BM Units can also be registered on the Self-Service Gateway (Elexon Kinnect Customer Solution).
What information do I provide on the BSCP15/4.14 form (where the Elexon Kinnect Customer Solution is NOT used)?	The Secondary BM Unit ID is V__XPPPPNNN, where X is the relevant GSP Group letter, PPPP is your four-letter Identifier (this may be the same as your Market Participant Identifier (MPID) if you are also a Supplier) and NNN are numbered sequentially, i.e. 001, 002 etc, for your identifier within each GSP Group. The NETSO will provide you with the NGC BM Unit ID. Enter a Production/Consumption (P/C) Flag of either P or C. This is only relevant for Parties who also have other Party roles under the BSC. If you are a VLP only, you must enter a C. If not sure, then enter a C. You need to state the date on which the Secondary BM Unit will be effective from.
When do I need to submit this information by?	You must submit the BSCP15/4.14 form at least 15 Working Days before your proposed Effective From Date. This must be on or later than the date that you become a VLP or AMVLP. BM Units can also be registered on the Self-Service Gateway (Elexon Kinnect Customer Solution).
Is there anything else I need to do?	VLPs need to allocate their SVA Metering System Id (MSID) Pairs to the Secondary BM Unit using the processes contained in BSCP602. AMVLPs need to register their Asset Metering Systems before allocating the Asset Metering System Id (AMSID) Pairs to the Secondary BM Unit using the processes contained in BSCP602.

Exempt Export Primary BM Units

What is an Exempt Export Primary BM Unit?	Some Generating Plants are ‘Exemptable’, which means that the Lead Party doesn’t need a Generation Licence. If the Lead Party of an Exemptable Generating Plant applies for and is granted exempt export status under the BSC, it can receive Embedded Benefits (if embedded) and declare its own P/C flag (embedded or directly connected).
What is the benefit of being Exempt Export?	For embedded Plant, depending on its the size, the benefits of being Exemptable apply to some or all of: Transmission Network Use of System (TNUoS) Charges; Balancing Services Use of System (BSUoS) Charges; and Transmission Losses. Further information can be found in the Embedded Generation and Embedded Benefits guidance. For Exempt Export Primary BM Units, you declare your own P/C Flag, which is then fixed. You are able to change your P/C flag as required but it will always take the flag that you choose.
How can I nominate a Primary BM Unit as Exemptable?	Some generators meet the conditions of a Statutory Instrument exempting them from the requirement to hold a Generation Licence. There are class exemptions which apply to all generators that meet the conditions and individual exemptions for other generators. More information can be found on the Department of Business, Energy and Industrial Strategy website. If you wish for your Primary BM Unit to be treated as exemptable under the BSC, you must apply for this status. You can do this with the initial Primary BM Unit Registration, or separately at a later date. Note that a Primary BM Unit associated with SVA registered Metering and Exempt Export status can only contain the Exemptable Generating Plant for which it is being registered, it cannot contain additional generation or demand. A Base Primary BM Unit can have an Exempt Export status, if it contains a single Exemptable Generating Plant. A Party that wishes to flag a Base Primary BM Unit as Exempt Export Status needs to ensure that they do not allocate any other Generation or Demand to that Primary BM Unit. Alternatively an Additional Supplier Primary BM Unit can be registered and flagged as Exempt Export Status to contain an Exemptable Generating Plant. Note that an Exemptable Generating Plant does not have to be included in an Exempt Export Primary BM Unit under the BSC; however exemptable benefits can only be applied to Exempt Export Primary BM Units.
What forms do I need to fill in (where the Elexon Kinnect Customer Solution is NOT used)?	For CVA Primary BM Units: You must submit BSCP15/4.5A to apply for the Exempt Export status for a CVA-registered Primary BM Unit and to choose the P/C Flag to Elexon at least 20 Working Days before the required date. Alternatively, this information can be completed via the Self-Service Gateway (Elexon Kinnect Customer Solution).	For SVA Primary BM Units: You must submit BSCP15/4.9A to apply for the Exempt Export status for an SVA-registered Primary BM Unit and to choose the P/C Flag to Elexon²⁸ at least 20 Working Days before the required date. Alternatively, this information can be completed via the Self-Service Gateway (Elexon Kinnect Customer Solution). If registering an Additional Primary BM Unit, you will also need to allocate the Metering System associated with the Exemptable Generating Plant to the Additional Primary BM Unit via BSCP503.
What other information is needed?	For CVA Primary BM Units: We need to check whether the Primary BM Unit is eligible to be Exemptable. Once Elexon has verified this, we will confirm or reject your application.	For SVA Primary BM Units: All you need to do is submit a BSCP15/4.9A form to us, and Elexon will confirm the status.
How do I change the P/C Flag?	Exempt Export Primary BM Units must elect their own P/C Flag when they are first registered as exemptable using the BSCP15/4.5A (CVA) or BSCP15/4.9A (SVA) form. If the Lead Party wishes to change the P/C Flag of an Exempt Export Primary BM Unit, the Lead Party must send the CRA and Elexon a BSCP15/4.8 form stating whether they will have a Production or Consumption Flag. Alternatively, this information can be completed via the Self-Service Gateway (Elexon Kinnect Customer Solution).

Other Considerations

Electricity Market Reform (EMR)

If you have a Contract for Difference or Capacity Market Contract, this may require you to set up your Primary BM Units in a particular configuration. The EMR Website lists all the latest news and industry information on EMR. You can also contact the team directly at contact@emrsettlement.co.uk.

Metered Volume Reallocation Notifications (MVRNs)

MVRNs are used to notify the BSC central systems that the energy flowing to or from a particular Primary BM Unit is to be allocated to one or more different Party’s Energy Accounts for the purposes of Energy Imbalance calculations.

There is more information on setting up Volume Notifications, including MVRNA Authorisations, in the Volume Notifications Guidance.

To set up a MVRNA Authorisation, you (the Lead Party), the relevant Notification Agent (MVRNA) and the Subsidiary Party each need to complete the relevant parts of a BSCP71/02 ²⁹ Form and send to neta@imserv.com, showing:

The relevant MVRNA i.e. the person responsible for submitting the MVRNs to central systems
The Lead Party for the Primary BM Unit i.e. the BSC Party FROM whom the metered volumes will be moved
The Subsidiary Party for the Primary BM Unit i.e. the BSC Party TO whom the metered volumes will be moved
The Lead Party Energy Account. This must be either Production or Consumption and must be the same as the Subsidiary Party Energy Account, and must match the Production/Consumption status of the Primary BM Unit
The Subsidiary Party Energy Account. This must be either Production or Consumption and must be the same as the Lead Party Energy Account, and must match the Production/Consumption status of the Primary BM Unit
The Primary BM Unit Identifier
The required Effective From Date

Note that you can only set up a MVRNA from a Production BM Unit to another BSC Party’s Production Account OR a Consumption BM Unit to another BSC Party’s Consumption Account. This should also be taken into consideration if you are also applying for Exempt Export status, as you can choose and fix the Production / Consumption Flag of the BM Unit.

Please note that until Elexon has issued the Approval to Energise email, your Primary BM Unit and the MVRNA Authorisation will not be registered in the BSC central systems. Your MVRNA will not be issued with the MVRNA Authorisation Identifier and unique MVRNA Key until after Elexon has issued the Approval to Energise email.

Please note that if the Approval to Energise Email is issued at least 2 WD before the Primary BM Unit EFD, then the MVRNA Authorisation Identifier and unique MVRNA Key can be issued to the MVRNA at latest 1 WD before the Primary BM Unit EFD, allowing the MVRNA to submit MVRNs from Settlement Period (SP) 1 of the Primary BM Unit EFD.

Example:

Primary BM Unit T_ELEX-1 has an EFD of 01/12/16 (a Thursday)
Elexon issue Approval to Energise Email before 14:00 29/11/16 (a Tuesday)
On 29/11/16, Primary BM Unit T_ELEX-1 entered into the central systems with an EFD of 01/12/16
On 29/11/16, Primary BM Unit T_ELEX-1 now entered into the central systems, allowing a MVRNA Authorisation for it to be created with an EFD of the next day, i.e. 30/11/16 (a Wednesday). MVRNA Authorisation Identifier and unique MVRNA Key then issued to MVRNA with an EFD of 30/11/16. (MVRNA Authorisation not valid before 30/11/16 so central System would reject any MVRN submission prior to that date)
On 30/11/16, MVRNA can submit MVRNs for Primary BM Unit T_ELEX-1 from at earliest SP1 of the Primary BM Unit EFD i.e. 01/12/16 (Primary BM Unit not valid before 01/12/16 so central System would reject any MVRN submission prior to that date)

Please note that if the Approval to Energise Email is not issued until 1 WD before the Primary BM Unit EFD, then the MVRNA Authorisation Identifier and unique MVRNA Key can be issued to the MVRNA, but the MVRNA Authorisation will not be valid until the same EFD as the Primary BM Unit, meaning that the MVRNA will not be able to submit MVRNs until at earliest midnight of the Primary BM Unit EFD, and that there will be a one Settlement Period (SP) gap in the MVRN (for SP 1), as Gate Closure will have passed for SP 1. You as the Lead Party may need to address this issue.

Example:

Primary BM Unit T_ELEX-1 has an EFD of 01/12/16 (a Thursday)
Elexon issue Approval to Energise Email before 14:00 30/11/16 (a Wednesday)
On 30/11/16, Primary BM Unit T_ELEX-1 entered into the central systems with an EFD of 01/12/16
On 30/11/16, Primary BM Unit T_ELEX-1 now entered into the central systems , allowing a MVRNA Authorisation for it to be created with an EFD of the next day, i.e. 01/12/16 (a Thursday). MVRNA Authorisation Identifier and unique MVRNA Key issued to MVRNA with an EFD of 01/12/16. (MVRNA Authorisation not valid before 01/12/16 so central System would reject any MVRN submission prior to that date)
On 01/12/16, MVRNA can, from at earliest midnight, submit MVRNs for Primary BM Unit T_ELEX-1, however the earliest SP will be SP2 on 01/12/16 (Primary BM Unit not valid before 01/12/16, and Gate Closure has passed for SP 1, so central System would reject any MVRN submission prior to that SP)

Trading Units

By default, all directly connected and embedded Primary BM Units are sole Trading Units. If your site consists of more than one Primary BM Unit then you may wish to set up a Trading Unit for the overall site. Being a Trading Unit allows all the Primary BM Units to be treated the same for:

Transmission Loss Multipliers (TLMs);
Production/Consumption flag; and
Certain BSC costs.

There are 14 Base Trading Units, one for each GSP Group. By default, all Supplier and SVA Exempt Export Primary BM Units will be added to the Base Trading Unit. If you do not want your SVA Exempt Export Primary BM Unit to be part of the relevant Base Trading Unit you need to apply for it to be part of a different Trading Unit.

You can apply for a Trading Unit via the Elexon Kinnect Customer Solution. Further information on Trading Units can be found on the Trading Units Section of the BSC Website and in BSCP31 ³⁰.

Trading Units

A Trading Unit is a Primary BM Unit or a combination of Primary BM Units. A ‘Sole’ Trading Unit is a Trading Unit containing one Primary BM Unit. There are 14 Base Trading Units, one for each GSP Group.

Being in a Trading Unit allows all the Primary BM Units to be treated the same for:
Transmission Loss Multipliers (TLMs);
Production/Consumption flag;

Certain BSC costs; and

Balancing Services Use of System (BSUoS) charges.

By default, all directly connected (T_) and embedded (E_) Primary BM Units are sole Trading Units. If your site consists of more than one Primary BM Unit then you may wish to set up a Trading Unit for the overall site.

There are 14 Base Trading Units, one for each GSP Group.By default, all Supplier and SVA Exempt Export Primary BM Units will be added to the Base Trading Unit. If you do not want your SVA Exempt Export Primary BM Unit to be part of the relevant Base Trading Unit you need to apply for it to be part of a different Trading Unit.

Further information on Trading Units can be found on the Trading Units section of the BSC Website, in BSCP31: Registration of Trading Units or by contacting trading.unit@elexon.co.uk.

BM Unit Charges

There is a monthly charge for some BM Units. These charges are set out in Section D of the BSC and further information can be found in the Schedule of Main and SVA Specified Charges.

Switching Groups

Some Offshore and onshore Power Park Modules (PPM) can be moved between Primary BM Units. You can set the relevant Primary BM Units up in a Switching Group, and opt to run the relevant PPM in any of the Primary BM Units within that Switching Group. To set this up, you must enter the relevant details in the table at the end of the BSCP15/4.1 form as well as submitting the applicable Aggregation Rules (BSCP75) for all the possible running configurations when you are registering the Aggregation Rules.

Guidance on Ccompleting form BSCP15/4.1 Registration of Primary BM Unit for a CVA Metering System (where the Elexon Kinnect Customer Solution is NOT used)

Please ensure that you are completing the most up to date version of the BSCP form by obtaining a new form from the BSC website for each new registration. The forms can be found under the BSCP section of the website. Please note that forms are directly below a given BSCP (as per the following example):

Participant Details

Please ensure that all of the Participant Details sections are completed, including the Party Id.

Authorised Signature

If the form is emailed, it must be emailed from the Authorised Signatories’ email address. The Authorised Signature can be left blank but the password must be completed. If the form is faxed or posted, the Authorised Signature and Password must be completed.

Primary BM Unit Registration Details

Primary BM Unit Registration Details

Primary BM Unit Id

Primary BM Unit Name (Max 30 Characters)

NG BM Unit ID

Primary BM Unit Type

Primary BM Unit Configuration

GSP Group Id

GC (MW)

DC (MW)

Inter-connector Primary BM Unit P/ C Flag

FPN Flag (Y/N)

Exempt Export (optional)

Inter-connector Id

Baselined BM Unit (Y/N)

EFD

Primary BM Unit Id – For directly connected, embedded and Interconnector Primary BM Units, if you have a NGC BM Unit Id this is either T_ (directly connected), E_ (embedded) or I_(Interconnector) followed by your NCG BM Unit Id. E.g. if you have a directly connected Unit with the NETSO where NGC BM Unit Id is ABCD-1, your BSC Primary BM Unit Id will be T_ABCD-1.

For directly connected or embedded Primary BM Units without a NGC BM Unit Id, your Primary BM Unit Id needs to start with either “T’ or ‘E_’ respectively. You can choose the rest of the Id up to a limit of 11 characters in total (i.e. including “T or ‘E_’).

For Supplier Primary BM Units, the Base Primary BM Unit ID is 2__XPPPP000, where _X is the relevant GSP Group letter, PPPP is your four-letter Supplier Market Participant Identifier (MPID), and 000 represents your Base Primary BM Unit. Additional Primary BM Units are normally numbered sequentially, i.e. 001, 002 etc., within each GSP Group.

Primary BM Unit Name – this is a free text field to identify the name of your Primary BM Unit, up to a limit of 30 characters.

NGC BM Unit Id – BSC Primary BM Units need to be registered with the NETSO and have a corresponding NGC BM Unit Id if their Generation or Demand Capacity is at or above 50MW in England and Wales, 30MW in South Scotland or 10MW in North Scotland. Below these limits you can choose whether or not you register a NCG BM Unit, although you will need to if you have a Bilateral Embedded Generation Agreement (BEGA) with the NETSO. Interconnector Primary BM Units always need to be registered with the NETSO. If you need to or choose to register your BM Unit with the NETSO, Youryour NGC BM Unit Id will be provided by them NETSO when you register your BM Unit with them. Please contact bmu.registration@nationalgrideso.com and transmissionconnections@nationalgrideso.com for information on registering your BM Unit with the NETSO and how to obtain a NGC BM Unit Id.

Primary BM Unit Type – please enter one of the following prefix letters depending on your Primary BM Unit type:

T – Directly Connected Primary BM Unit, connected to the Transmission System;
E – Embedded Primary BM Unit, connected to a Distribution System;
I – Interconnector Primary BM Unit;
G – Base Supplier Primary BM Unit; or
S – Additional Supplier Primary BM Unit.

Primary BM Unit configuration - please enter one of the following letters depending on your Primary BM Unit configuration:

CCGT – Combined Cycle Gas Turbine registered in Central Meter Registration Service (CMRS);
PPM – a single Power Park Module registered in CMRS;
COBMU – a Combined Offshore BM Unit comprising 2 or more Offshore Power Park Modules registered in CMRS. This configuration must be agreed by the NETSO;
DC – Directly Connected Circuit at Customer (Supplied by BSC Party) Premises (there must be one Primary BM Unit for each circuit connected to the Transmission System);
DC+ – Directly Connected Circuit at Customer (Supplied by BSC Party) Premises through more than one Boundary Point. Total demand must be less than 50MW in England and Wales, 30 MW in South Scotland and 10 MW in North Scotland;
IC – Interconnector Primary BM Unit;
BB – Supplier Base Primary BM Unit. There will be 14 of these on the form, one for each GSP Group;
AB – Additional Primary BM Unit;
OPPM+ - Offshore PPM plus related Imports at separate Boundary Points;
COBMU+ - COBMU plus related Imports at separate Boundary Points;
MC – Meets criteria in BSC K3.1.2. If meets criteria is selected, you need to complete the table in the form to confirm you meet the five criteria for a Primary BM Unit detailed in Section K 3.1.2 of the BSC; or
NS – Non-Sstandard Primary BM Unit. If Nnon-Sstandard Primary BM Unit is selected, you also need to submit a BSCP15/4.13 form.

GSP Group Id – This only needs to be completed for embedded and Supplier Primary BM Units, the GSP Group that the Primary BM Unit contributes to. For all other Primary BM Units leave this blank.

GC – Generation Capacity which is the maximum expected net Generation for the Primary BM Unit in its first BSC Season.

DC – Demand Capacity which is the maximum expected net Demand for the Primary BM Unit in its first BSC Season.

Interconnector Primary BM Unit P/C Flag – This only needs to be completed for Interconnector Primary BM Units. For the Primary BM Unit with a positive GC and a zero DC, enter a ‘P’ for P/C Flag. For the Primary BM Unit with a zero GC and a negative DC enter a ‘C’ for the Flag. For all other Primary BM Units leave this blank.

FPN Flag – This needs to be ‘Y’ for any Primary BM Unit with a NGC BM Unit Id and ‘N’ for any Primary BM Units without a NGC BM Unit Id.

Exempt Export – If your Plant and Apparatus is exempt from the requirement to hold a Generation Licence, you may wish to flag your Primary BM Unit as Exempt Export under the BSC, enter ‘Y’ and submit either a BSCP15/4.5A (for directly connected or embedded Primary BM Units) or BSCP15/4.9A (For Base and Additional Primary Supplier BM Units) form along with your BSCP15/4.1 form.

Interconnector Id - This only needs to be completed for Interconnector Primary BM Units and should be one of the following:

FRANCE;
MOYLE;
BRITNED;
EWIC;
NEMOLINK;
ELECLINK; or
IFA2;
NSL;
VIKINGLINK; or
GREENLINK.

Baselined BM Unit – This only needs to be completed for Additional BM Units. For information about baselined BM Units, please refer to Wider Access Guidance For Virtual Lead Parties (VLPs), Asset Metering VLPs and Suppliers.

EFD – This is the best estimate of the earliest Effective From Date for the Primary BM Unit. If the date moves back from the one submitted on the BSCP15/4.1 form, there is no need to submit another form. However, if the date moves forward, you will need to submit another form.

Electrical Single Line Diagram

For all registrations of directly connected and embedded Primary BM Units, please ensure that you submit electrical single line diagram(s) showing:

the location of the Metering Equipment, in particular the Settlement current and voltage transformers (CTs/VTs) and CT/VT ratios; and
any existing Boundary Points and/ or System Connection Points at or near the proposed Boundary Point(s); and
any back up SVA connection and interlocking arrangements.

Please tick the box on the form to show that the diagram has been submitted.

Primary BM Unit meeting criteria

If your Primary BM Unit meets the criteria set out in section K3.1.2 of the BSC, you need to confirm that it meets each criteria using the table in the BSCP15/4.1 form. If any of the criteria are not met, you will also need to complete a BSCP15/4.13 form to apply for a Non-Standard BM Unit.

Fuel Type (Directly Connected or Embedded Primary BM Units) – for use in calculation of CALF values

Please indicate the fuel type for the Primary BM Unit from the list contained in the table.

Primary BM Unit and Associated CVA Metering Systems

If this is a registration of an embedded or directly connected Primary BM Unit and you already have a CVA Metering System Identifier (MSID)³¹ , please enter it here. If you do not have a MSID, please leave this section blank. For all other registrations, leave this section blank.

MPAN Mapping details

If this is a Registration Transfer from SVA to CVA in accordance with BSCP68, please enter the MPANs related to the SVA registration here with the Effective To Date. For all other registrations, leave this section blank.

Primary BM Unit Group Details

This section in BSCP15 is no longer needed as the corresponding section of the BSC was removed by Approved Modification P394. Leave this section blank.

Switching Groups

If a Power Park Module could be part of more than one Primary BM Unit, then each of the Primary BM Units that it could be part of needs to be included here as a Switching Group, even if you have no intension of switching that Power Park Module between Primary BM Units. You form may have more than one Switching Group if there are multiple Power Park Modules that could belong to more than one Primary BM Unit.

Need more information?

For more information please contact the please raise a case through Elexon Support: https://support.elexon.co.uk/csm.BSC Service Desk at bscservicedesk@cgi.com or call 0370 010 6950.

You can find out more here:

Intellectual Property Rights, Copyright and Disclaimer

The copyright and other intellectual property rights in this document are vested in Elexon or appear with the consent of the copyright owner. These materials are made available for you for the purposes of your participation in the electricity industry. If you have an interest in the electricity industry, you may view, download, copy, distribute, modify, transmit, publish, sell or create derivative works (in whatever format) from this document or in other cases use for personal academic or other non-commercial purposes. All copyright and other proprietary notices contained in the document must be retained on any copy you make.

All other rights of the copyright owner not expressly dealt with above are reserved.

No representation, warranty or guarantee is made that the information in this document is accurate or complete. While care is taken in the collection and provision of this information, Elexon Limited shall not be liable for any errors, omissions, misstatements or mistakes in any information or damages resulting from the use of this information or action taken in reliance on it.

1 Bmu.registration@nationalgrideso.com and transmissionconnections@nationalgrideso.com

2 Bmu.registration@nationalgrideso.com and transmissionconnections@nationalgrideso.com

3 neta@imserv.com

4 A Metering System ID (MSID) for your BM Unit can be reserved by contacting the CRA.

5 The Aggregation Rules guidance explains how to write your Aggregation Rules.

6 Bmu.registration@nationalgrideso.com and transmissionconnections@nationalgrideso.com

7 neta@imserv.com

8 A Metering System ID (MSID) for your BM Unit can be reserved by contacting the CRA. If you are registering both Export and Import relating to the site, then you will need to check with the LDSO if they intend to apply a separate CVA Line Loss Factors (LLFs) to the Export and to the Import – if so, then you will need two MSIDs (one for Export, one for Import).

9 The Aggregation Rules guidance explains how to write your Aggregation Rules.

10 Further information can be found in the Embedded Generation and Embedded Benefits guidance.

11 Small Power Station is defined in the Grid Code as a Power Station with a Registered Capacity of less than 50MW in England and Wales, less than 30MW in South Scotland and less than 10MW in North Scotland and Offshore.

12 The NETSO must agree that two or more Power Park Modules can be combined into a Combined Offshore BM Unit.

13 BSCP20 ‘Registration of Metering Systems for Central Volume Allocation’

14 This form appoints the MOA, however the MOA may object to the appointment if they don’t believe that they are the MOA for the Metering System.

15 BSCP75 ‘Registration of Meter Aggregation Rules for Volume Allocation Units’

16 BSCP32 ‘Metering Dispensations’

17 Code of Practice 4 ‘The Calibration, Testing and Commissioning Requirements of Metering Equipment for Settlement Purposes’

18 BSCP02 ‘Proving Test Requirements for Central Volume Allocation Metering Systems’

19 BSCP 25: Registration of Transmission System Boundary Points, Grid Supply Points, GSP Groups and Distribution Systems Connection Points

20 BSCP128: Production, Submission, Audit and Approval of Line Loss Factors.

21 Bmu.registration@nationalgrideso.com and transmissionconnections@nationalgrideso.com

22 Note that if you have a contact with the NETSO to participate in the Balancing Market with these BM Unit, it may require you to register Additional BM Units as opposed to an additional MPID.

23 Based on the 2024/25 monthly change of £60 per BM Unit per month.

24 Bmu.registration@nationalgrideso.com and transmissionconnections@nationalgrideso.com

25 mddc@elexon.co.uk

26 Note that if you have a contact with the NETSO to participate in the Balancing Market with these BM Unit, it may require you to register Additional BM Units as opposed to an additional MPID.

27 Bmu.registration@nationalgrideso.com and transmissionconnections@nationalgrideso.com

28 Bm.unit@elexon.co.uk

29 BSCP71 ‘Submission of ECVNs and MVRNs’

30 BSCP31 ‘Registration of Trading Units’

31 A Metering System ID (MSID) for your BM Unit can be reserved by contacting the CRA (neta@imserv.com).

Guidance Notes

CONTENTS

BM Units – Registration of Balancing Mechanism (BM) Units

What is a BM Unit?

Accessing the Elexon Kinnect Customer Solution

What do I need to do before I can register BM Units?

NETSO Requirements

Types of BM Units

Exempt Export Primary BM Units

Standard and Non-Standard Primary BM Unit Configuration

0.0.1 1 the Registered Capacity of the Boundary Point measured by the Metering System(s) registered in SMRS is equal to or less than the limit determined by the Panel, currently 415V;

2. the Plant and Apparatus cannot Export through the Metering System registered in SMRS; and

3. there are measures in place to prevent instantaneous flow through of electricity:

Permissible Configurations of Plant and Apparatus

Configurations of Plant and Apparatus not Permissible (unless agreed by the ISG)

What is a Directly Connected Primary BM Unit?

What is an Embedded Primary BM Unit?

How long does it take to register a Directly Connected or Embedded BM Unit?

How do I register a Directly Connected or Embedded BM Unit?

What else is needed before the BM Unit can go live?

Switching Groups

Approval to Energise

Registration of Interconnector Primary BM Units

What is an Interconnector Primary BM Unit?

How do I register an Interconnector BM Unit?

Registration of Supplier Primary BM Units (2_Primary BM Units)

What is a Supplier Primary BM Unit?

How do I register Base Supplier BM Units?

How do I register an Additional Supplier BM Unit?

Is there anything else I need to do?

Are there any other options?

Supplier Primary BM Units (C_Primary BM Units) for EMR

Registration of Secondary BM Units (V_BM Units)

Secondary BM Units (V_Secondary BM Units)

What is a Secondary BM Unit?

How do I register a Secondary BM Unit?

Is there anything else I need to do?

MSID Registration

AMSID Registration

Other Considerations

Electricity Market Reform (EMR)

Metered Volume Reallocation Notifications (MVRNs)

Trading Units

Trading Units

BM Unit Charges

Switching Groups

Guidance on Ccompleting form BSCP15/4.1 Registration of Primary BM Unit for a CVA Metering System (where the Elexon Kinnect Customer Solution is NOT used)

Participant Details

Authorised Signature

Primary BM Unit Registration Details

Electrical Single Line Diagram

Primary BM Unit meeting criteria

Fuel Type (Directly Connected or Embedded Primary BM Units) – for use in calculation of CALF values

Primary BM Unit and Associated CVA Metering Systems

MPAN Mapping details

Primary BM Unit Group Details

Switching Groups

Need more information?