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Governance scenario

Nuclear Safety Event

The Office for Nuclear Regulation receives a safety concern report at a fictional AGR station. NESO must balance safety scrutiny, public communication, and maintaining generation adequacy.

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This is a fictionalised teaching scenario grounded in real institutional roles, published reforms, and current public-source context.

Scenario player

Work through the decision path below. Each choice changes the route, the institutional trade-offs, and the metrics the scenario tracks.

Nuclear Safety Event

Step 1 of 2

ONR

Safety concern reported

The Office for Nuclear Regulation receives a report that a control system at Hartwell AGR station has not been fully tested against a specific fault scenario. The station is currently operating at full capacity and provides 7% of GB generation. ONR must decide whether to order immediate shutdown pending investigation or allow continued operation with increased monitoring.

What is at stake

  • -If you shut down without full investigation, you lose 7% of generation during cold winter and risk blackouts.
  • -If you allow operation without fully investigating, you risk a safety incident.
  • -Public reaction to either decision will be intense.

What is your immediate safety decision?

Current Metrics

System Security72
Customer Protection75
Net Zero Progress65
Affordability62
Operational Efficiency60
Stakeholder Trust68

Actors Involved

ONRNESOOfgemCitizensHSE

Regulatory Context

Nuclear Installations Act and Safety and Security Policy Framework

Governance relationship map

View mode

Operating loop breadcrumb

Governance→Planning→Operations→Outcomes→Evidence

Current focus: Rules and accountability

Legend

Governance and policy

Rules, remits, and accountability

Planning and investment

Connections, queue progression, and delivery planning

System operations

Real-time balancing and network operation

Market and consumer outcomes

Prices, settlement, reliability, affordability

Evidence and learning

Telemetry, assurance, and continuous improvement

Glossary

  • Dispatch

    Real-time instructions to increase or reduce generation or demand so supply stays in balance.

  • Balancing

    The continuous process of matching electricity supply to demand while maintaining system frequency.

  • Constraint

    A technical limit in the network that restricts how power can flow under current conditions.

  • Industry code

    A formal rulebook that defines obligations and processes for specific market and network activities.

  • Connection agreement

    The formal agreement setting technical and milestone conditions for connecting a project to the network.

  • Settlement

    The process that turns metered and contractual positions into final market cashflow outcomes.

  • Conformance gate

    A quality checkpoint that verifies whether data or implementation meets agreed standards.

  • LTDS

    Long Term Development Statement publication requirements for distribution network data.

Guided tour

Step 1 of 8

Who sets the rules?

Start with governance: policy direction, regulatory oversight, licences, and code obligations.

Why it matters: Newcomers should first understand where authority sits before interpreting operational decisions.

Open Ofgem licence and code guidance

Preparing system graph…

Use this map to keep scenario decisions anchored to policy, coordination, operational delivery, and evidence feedback relationships.

Sources and methodology

How this page was assembled

Scenarios are designed as regulator-safe teaching runs. Institutional roles, programme context, and cited reform pathways stay grounded in current public sources, while event details and numbers inside the run remain fictionalised unless explicitly evidenced elsewhere. This scenario is framed against Nuclear Installations Act and Safety and Security Policy Framework.

Last reviewed 18 March 2026

Primary sources

Ransford's Notes