Four changes to BSC Audit for 2018/2019

Over recent months we have been reviewing the BSC Audit process to ensure that it works well for those involved. We have looked as the Audit Intensity, site visits, DTN testing and data requests.

Here is a summary of the review and changes for the 2018/19 audit cycle. We would value your feedback.

Audit Intensity and PAP Selection

For the 2018/19 Audit Year and for all future audit cycles, ELEXON will be responsible for determining the audit intensity of each audited Supplier and Supplier Volume Allocation agent.

The methodology by which Audit intensities are set has been designed to be risk-focused, targeting PAPs which represent the greatest risk to Settlement based on a broad variety of factors.

Below is a list of high level principles that can contribute to a PAP being selected for the BSC Audit and by which the intensity of the Audit would then be set:

  • Significant changes in Metering System ID (MSID) counts in the current or preceding Audit period (considering both percentage and count)
  • Number and rating of open Material Issues from prior Audit periods
  • Specific PAB or Industry concerns (e.g. the recent increase in ‘Off the Shelf’ Suppliers and Supplier Agents)
  • Audit rotation (every PAP will be subjected to a Full Intensity Audit at least once every four years)
  • Evidence from other Performance Assurance Techniques including BUSRRs, Qualification, TAPAP, TAA and Trading Disputes
  • MSID counts above the predetermined thresholds for each Audited role (used as a guide rather than a strict criteria)
  • Discussions with OSMs and other ELEXON SMEs

Data Transfer Network Testing

ELEXON and the BSC Auditor have been working to improve the DTN testing to reduce the level of market false positives from previous audit cycles.

We have focussed on the most frequently performed tests, with the reduction in market false positives ranging from 40% to 94% depending on the test.

For the tests that have not yet been through this process of review, improvement and testing have been removed and manual testing will be undertaken instead.

As part of this improvement process, ELEXON has sought approval from the Performance Assurance Board to add 12 new Data flows to the monthly set currently being used, with the aim to use these flows to further reduce false positives.

Once we have been able to ensure the effectiveness of the current suite of DTN tests we hope to eventually use these additional flows to develop additional DTN tests.

Data Request Reduction

ELEXON and the BSC Auditor are working together to utilize DTN Data and wider industry data to reduce the overall number of data requests made as part of the Audit.

Below is a graph that gives clear visibility of the individual impact to the audit by role:

Graph showing 2018/2019 BSC Audit Effort: Reduction in Data Requests
Graph showing 2018/2019 BSC Audit Effort: Reduction in Data Requests

As can be seen from the chart above we have made significant reductions in the number of data requests which will be required during the 2018/19 audit cycle.

Medium/Targeted and Limited scope may have ad-hoc papers (based on issues) scoped in therefore those numbers might differ slightly.

Therefore, below is a view of how this affects the overall number of Data Requests, with an approximate reduction of 25%.

We will continue this work and hope to achieve further reductions in future audit cycles.

Graph showing BSC Audit Year Data Request Reductions 2018/2019
Graph showing BSC Audit Year Data Request Reductions 2018/2019

Site Visit Notice

Work is currently under way to ensure that the 2019/20 audit selection and audit intensity processes are completed earlier than in previous years, allowing for an initial draft of the Audit Schedule to be developed and for initial notifications to be issued as early as summer 2019.

The intention behind this is to give PAPs more notice ahead of site visits. We hope that this will be an improvement over current and past audit cycles.

In addition to this, from the 2018/19 Audit cycle onwards, provision has been made to allow for Audits on specific Parties to be repeated within the same Audit period where necessary.


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