CMP475 Balancing Services Use of System (BSUoS) urgency decision
- Publication type:
- Code modification
- Publication date:
- Topic:
- Energy codes,
- Electricity transmission
- Subtopic:
- Connection and use of system code (CUSC)
Outcome of request for an urgent review of proposed changes to Connection and Use of System Code CMP475, Amendment to the BSUoS tariff reset process.
Details of outcome
On 15 April 2026, the National Energy System Operator (NESO) raised the Connection and Use of System Code CUSC Modification Proposal CMP475: ‘Amendment to the BSUoS tariff reset process’.
On 21 April 2026, the CUSC Panel wrote to inform us of its unanimous view that CMP475 should proceed as an Urgent CUSC Modification Proposal.
We have decided to accept the request for urgency for CMP475. This letter sets out our reasoning.
Code modification description
This proposal concerns change to the Balancing Services Use of System (BSUoS) tariff reset process within the Connection and Use of System Code. BSUoS charges are used to recover the costs incurred by the National Energy System Operator in balancing the electricity system and are currently set as fixed tariffs over defined periods.
CMP475 to enable the reopening of fixed BSUoS tariff periods where NESO forecasts that the WCF will be exceeded, and to introduce a mechanism to allow recovery of the WCF position toward a neutral level within a tariff period.