RIIO-2 Network Asset Risk Metric methodologies audit

Publication type:
Consultation
Publication date:
Last updated:
Closed date:
Status:
Closed (with decision)
Topic:
Electricity transmission,
Gas transmission,
Gas distribution
Show all updates
This consultation has concluded

Our assessment of proposed modifications to the Network Asset Risk Metric methodologies used in the energy transmission and gas distributions sectors.

Details of outcome

We have approved amendments to the RIIO-2 Network Asset Risk Metric (NARM) methodologies for electricity transmission, gas transmission and gas distribution, following the consultation published on 20 February 2026. The main changes are:

  • making sure the way energy companies assess and report network risk is consistent
  • improving the ability to trace model inputs and assumptions
  • supporting the operation of the NARM mechanism within the RIIO-2 network price controls

Read the full outcome

Modifications to RIIO-2 Networks Asset Risk Metric (NARM) consultation decision [PDF, 138.31KB]
Direction to modify the Special Conditions of the Electricity Transmission Licences [PDF, 101.88KB]
Direction to modify the Special Conditions of the Gas Transporter Licence [PDF, 107.43KB]
Northern Gas Networks (NGN) response to Modifications to RIIO-2 Networks Asset Risk Metric (NARM) consultation [PDF, 401.62KB]
National Grid Electricity Transmission (NGET) response to Modifications to RIIO-2 Networks Asset Risk Metric (NARM) consultation [PDF, 174.54KB]
SGN response to Modifications to RIIO-2 Networks Asset Risk Metric (NARM) consultation [PDF, 187.32KB]

Consultation description

During RIIO-2, audits were completed across the electricity transmission, gas transmission and gas distribution sectors. These outlined 3 different categories of changes needed.

This consultation sets out the changes proposed by gas distribution networks, electricity transmission owners and National Gas Transmission and our assessments of these.

Who should respond

We would like views from licensees and other gas and electricity network companies, particularly those with an interest in Network Asset Risk Metrics.

All updates

8 June 2026 details of outcome, direction to modify special conditions and non-confidential responses added.