NGN ISG Blog
Independent Stakeholder Group Update – December 2025
The Northern Gas Networks Independent Stakeholder Group (ISG) met in person in December 2025 to review Ofgem’s Final Determination for RIIO-GD3, reflect on priorities for the year ahead, and agree how the ISG will operate as NGN moves into the new price control period.
GD3 Final Determination and Business Update
The ISG received an update on NGN’s Final Determination outcome and the wider regulatory and policy context.
Discussion focused on the challenges created by ongoing policy uncertainty (like Hydrogen for heating), the balance between productivity expectations and service delivery, and the importance of maintaining safety, resilience, and customer outcomes in the early years of GD3. Members also discussed the limited clarity on Ofgem’s ongoing monitoring approach and the role the ISG could play in providing proportionate, independent assurance (the NGN ISG is working with OFGEM on this).
The ISG’s Role in GD3
The ISG reviewed how its role should evolve in GD3.
Members agreed there should be greater focus on early challenge of strategies and decisions, clearer visibility of how ISG input influences outcomes, and continued emphasis on representing future customers through the Junior ISG and Young Innovators Council. The importance of maintaining independence from both NGN and Ofgem was also reinforced.
Environment, Shrinkage and Leakage
NGN presented an update on shrinkage and leakage performance, including GD2 delivery and GD3 targets.
The ISG welcomed strong historic performance but discussed the limitations of existing shrinkage models and the reputational risks if future data diverges from long-held assumptions. Members encouraged transparency, robust scenario planning, and clear communication on environmental impacts.
An update on NGN’s electric vehicle trial was also received, with positive early findings and no impact on emergency response performance. This is something the IGS has been pushing for throughout GD2 and was encouraged to see this progress.
Biomethane and Energy Futures
The ISG discussed NGN’s biomethane strategy and wider industry developments.
Members noted that policy uncertainty and grid access remain the main barriers to growth, rather than feedstock availability. While welcoming NGN’s ambition in GD3, the ISG challenged whether targets are achievable without clearer long-term government policy and successor support mechanisms.
Operational issues such as summer constraints, capacity utilisation, and variability of gas quality were also discussed. There will be incentives in GD3 to support biomethane.
Vulnerability, VCMA and Governance
The ISG considered VCMA governance in GD3 and NGN’s ongoing engagement with Ofgem and other stakeholders (this was discussed in the Oct ISG).
Members emphasised the importance of ensuring VCMA funding is spent as effectively as possible to support vulnerable customers, particularly those in fuel poverty or debt, while maintaining strong carbon monoxide awareness and safety outcomes. The ISG also discussed opportunities to strengthen assurance, transparency, and learning across the sector.
2026 Work Plan and Next Steps
The ISG reviewed the draft 2026 work plan and supported a greater focus on early GD3 delivery risks, vulnerability and affordability, and more operationally focused deep dives.