Large scale change to Market Domain Data

Find out the latest updates for 28 September 2020 regarding the submission of Market Domain Data (MDD) Plan for Ofgem’s Targeted Charging Review (TCR).

Testing is required to make sure all BSC Parties will be able to load significantly larger Market Domain Data (MDD) and Line Loss Factor (LLF) files after participants provided their views on the potential impacts of adding large numbers of new Line Loss Factor Class Identifiers (LLFCs) – approximately 19,000 – and valid set combinations – approximately 300,000.

The testing is to ensure that there is not a risk to Settlement.

In August, we issued a Request for Information (RFI) so that BSC Parties could provide views on the potential impacts of adding large numbers of LLFCs and valid set combinations to MDD.

The MDD published in October included ~2,122 Target Charging Review (TCR) LLFCs and ~24,000 valid set combinations, which were approved by the Panel in their September 2020 meeting, in addition to the business as usual CRs that were approved by SVG. The October MDD was published on 14 October 2020 and went live on 21 October 2020.  As of today, we have not been made aware of any negative impact on parties’ systems, however please contact us should you have an issue to report.

Latest update

Files undelivered due to upgrades

Seven files were not delivered to their intended recipients, following the recent D0269 Market Domain Data (MDD) release by Elexon. This was due to a minor configuration issue following the Energy Market Data Hub (EMDH) upgrades carried out by ElectraLink. 

Once this issue was identified, the configuration was adjusted to the correct level and the issue was resolved, allowing these files to be delivered and received by customers.

This did not affect the other D0269 flows, which were successfully delivered to their intended recipients.

Since this issue has been raised, ElectraLink has investigated all other gateways and can confirm that this issue has not impacted any other Data Transfer Service (DTS) users and it will not cause any issues for Elexon in future.

Progress made for Target Charging Review 

The BSC Panel was provided with an update on the progress Elexon has made on the Market Domain Data (MDD) and Line Loss Factor Classes (LLFC) plan for Ofgem’s Targeted Charging Review (TCR). This includes the risks, migrations and proposed next steps.

Next steps

Currently, we are in the process of assessing, as a minimum, providing test files for MDD(D0269/D0270) and LLFs(D0265). We will be distributing an indicative plan to Licensed Distribution System Operator (LDSO) and Independent Distribution Network Operators (IDNOs) once the expected testing timescales have been agreed and finalised.

On 11 November 2020, Elexon will publish an MDD/TCR Change Request (CR) containing ~1,638 LLFCs and ~37,000 new valid set combinations.

This change was approved at the Supplier Volume Allocation Group (SVG) meeting on 6 October 2020.

Should you experience any impact on your systems, please contact the MDD Coordinator or Line Loss Factors Coordinator.

We intend to take the remaining Host DNO TCR CRs for approval to the 1 December 2020 SVG meeting (for go live in January 2021), in parallel to running industry testing and based on the performance of both the October and November MDD publishes. This is a risk-based approach as the Host DNO submissions account for 10% of the total TCR volume and over 98% of the MPAS transfers.

We will make sure that the participants are kept informed with regards to testing and are provided with sufficient notice prior to TCR submission dates.

Previous progress on MDD Change requests

BSC Panel     

At the BSC Panel on 10 September 2020, the Panel considered Market Domain Data Change Requests for Version 302/303 – (306/05).

 The BSC Panel:

  • approved Change Requests M3629 and M3631 which include LLFCs to support both the TCR and other billing requirements.
  • deferred Change Requests M3630 and M3632, which only contain changes to support the TCR, until further information on the 1 April 2021 deadline and testing has been provided.

BSC Panel

Supplier Volume Allocation Group (SVG)

At the SVG Meeting (SVG235/01) on 1 September 2020, the first set of submissions to support the implementation of Ofgem’s TCR Significant Code Review (SCR) were presented to the SVG for approval.

They considered four TCR related Change Requests, for implementation in Version 303 of MDD with a go-live date of 21 October 2020.

The SVG could not reach a decision to approve the Change Requests, so they were referred to the BSC Panel at their meeting on 10 September 2020.

Ofgem’s Targeted Charging Review

On 18 December 2019, Ofgem concluded its TCR: SCR. As part of its final decision, Ofgem directed the LDSOs and National Electricity Transmission System Operators (NETSO) to make changes to how residual Distribution Use of System (DUOS) and Transmission Network Use of System (TNUoS) network charges are set and recovered in Great Britain.

In January 2020, LDSOs and NETSO raised Distribution Connection and Use of System Agreement (DCUSA) and CUSC Modifications to give effect to the TCR: SCR Decision.

More about MDD changes

Find out more about the large scale changes to MDD based on Ofgem’s TCR.


Click on the X next to any of the icons to replace them with a short-cut link to the page you are currently on or search for a specific page.