Balancing and Settlement Code

The Balancing and Settlement Code (BSC) is the rulebook for how electricity is traded and settled in Great Britain. When a generator produces power or a supplier buys it, the BSC governs how imbalances between what was contracted and what actually happened get priced and charged. Elexon administers the code on behalf of the industry.

Four types of change

Modifications (P-numbers) change the BSC itself. They go through: Raised → Initial Written Assessment → Assessment Procedure (a Workgroup of 5+ industry experts develops the solution and consults industry) → Report Phase (the BSC Panel recommends, industry consulted again) → Decision → Implementation. Typically 6–8 months to decision. Ofgem makes the final call unless the change qualifies as Self-Governance, in which case the Panel decides and parties can appeal.

Change Proposals (CP-numbers) change subsidiary documents and systems, not the BSC itself. Simpler process, about 3 months. Decided by Panel Committees.

Issues are investigations where the problem is known but the solution isn't. An Issue Group explores options. No set timeline. If a solution emerges, a Modification or CP follows.

Standard Changes (SC-numbers) are pre-authorised routine changes. Low risk, repeatable, minimal process.

Key concepts

• Self-Governance applies when a Modification won't materially affect consumers, competition, or system operation, the BSC Panel can decide it without Ofgem. Parties get 15 working days to appeal.
• EBGL (European Balancing Guideline). Modifications affecting EBGL Article 18 provisions cannot be Self-Governance and require Ofgem's decision.
• Urgent modifications can skip the Assessment Procedure and go straight to Report Phase on a compressed timeline. Ofgem decides urgency.