National Grid Electricity Transmission: audit of substations
- Publication type:
- Transparency document
- Publication date:
- Topic:
- Electricity transmission
Findings and recommendations from the independent audit of National Grid Electricity Transmission’s (NGET) substations.
In March 2025, a fire at the North Hyde substation impacted Heathrow Airport. Following this, we have asked National Grid Electricity Transmission (NGET) to arrange a technical audit of some of their substations.
Det Norske Veritas (DNV) carried out the independent audit of equipment at 20 substations. This included a review of NGET's policies and processes for carrying out maintenance on the equipment.
DNV’s overall conclusion is that NGET adheres to good asset condition, health data management and general asset management practices.
Based on the report findings, we have asked NGET to review 5 broad areas for review and improvement.