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Section S, Annex S-1 – Performance Levels and Supplier Charges

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Section S Annex S-1: Performance Levels and Supplier Charges

Simple Guide


Annex S-1 defines Performance Levels and Serials required of Suppliers and their Supplier Agents. In addition, it also defines the Menu of Supplier Charges that specifies the value of each charge, should each Supplier or its Supplier Agents deviate from these Performance Levels. The arrangements for the payment of such charges are also defined.

Performance Levels

Non Half Hourly (NHH) performance is measured by the total energy settled on Annualised Advances, as a percentage of a Supplier’s NHH total energy, with these performance levels being measurable in each Grid Supply Point (GSP) Group. A Supplier is responsible for achieving NHH Performance Levels in each GSP Group ranging from 30% to 97%. These performance levels apply to the relevant Supplier Volume Allocation runs (i.e. First Reconciliation Volume Allocation through to Final Reconciliation Volume Allocation).

The Half Hourly (HH) performance level (99%) is defined as the proportion of energy a Supplier settles based on actual, rather than estimated, data for its 100kW Metering Systems, at each Supplier Volume Allocation run. The remaining 1% may be settled using estimated data. For Half Hourly Non-100kW Metering Systems, 90% of energy must be settled on actual data by the First Reconciliation Volume Allocation Run. A performance level of 99% applies to all subsequent Supplier Volume Allocation Runs.

Charges are also levied for each 100kW premise that has not had Half Hourly Metering installed (after the "SP04 Completion Date" as defined in Annex S-1) under the SP04 Serial. The Supplier must submit the number of days when HH metering should have been installed (i.e. the days after the BSC deadline) and the number of days when HH metering failed to be installed for each relevant MSID in the GSP Group.


A menu of charges, payable by Suppliers, is set out in the event that Suppliers or their Supplier Agents fail to meet the defined Performance Levels. The charges to each Supplier in respect of a given GSP Group in a given month are capped. A GSP Group cap is calculated by the Performance Assurance Board (PAB) annually. Each month the Supplier’s cap is calculated for each GSP Group based on its proportion of energy attributable to that GSP Group.

Collection and Payment of Supplier Charges

The PAB decides whether a Supplier has failed to comply with the relevant Performance Levels. The PAB will make its determination for SP08 Serials on the basis of information supplied to the SVAA for each Settlement Date, for each Settlement Run type and for each GSP Group against the performance standards detailed in Annex S-1 of the BSC. Following implementation of P393 ‘Disapplication of Supplier Charge SP01’ Modification in 27 February 2020, charges for SP01 Serial noncompliance is set to a value of zero. In addition to this, historic missing data for which an SP01 Charge is applicable would also revert to zero.

If the PAB determines that Performance Levels have not been complied with and charges are payable, each relevant Supplier is notified of the amount of charges and required to pay them within 15 days after the date of the invoice.

Need more information?

For more information please contact the BSC Service Desk at or call 0370 010 6950.

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