IN Brief:
- Ofgem has published its ED3 Sector Specific Methodology Decision for electricity distribution networks.
- The 2028–2033 price control will shape investment across Britain’s five DNOs and 14 licence areas.
- Resilience funding, flexibility, and delivery incentives remain central issues as demand growth and climate risk increase.
Ofgem has published the Sector Specific Methodology Decision for RIIO-ED3, setting out how Britain’s electricity distribution networks will be assessed as they prepare investment plans for the 2028–2033 price control period.
The decision sets the rules for how distribution network operators should keep pace with projected electricity demand while controlling costs. The five DNOs — UK Power Networks, National Grid Electricity Distribution, Scottish and Southern Electricity Networks, SP Energy Networks, and Northern Powergrid — must submit business plans in December, with draft determinations expected next summer and final decisions by the end of 2027.
ED3 will cover 14 regional licence areas and will shape investment across more than 800,000km of distribution networks, hundreds of thousands of substations, and millions of assets. The period begins on 1 April 2028 and runs to 31 March 2033.
Ofgem has described its approach as a more disciplined price control. DNOs will need to justify proposed expenditure through engineering evidence and benchmarking before funding is approved. Baseline allowances will be set conservatively, while in-period uncertainty mechanisms, volume drivers, reopeners, and pass-through costs will allow additional funding to be released as demand becomes clearer.
The regulator has also emphasised a “build and flex” model. New investment should be approved where strategic need is clear and where networks have maximised existing grid capacity using smart and flexible technologies. That approach is intended to reduce speculative reinforcement while still allowing networks to invest where electrification is likely to create bottlenecks.
Resilience sits inside that framework, but the treatment remains contested. Industry concern remains that ED3 still lacks a direct financial incentive specifically designed to reward resilience investment. Ofgem’s methodology includes stronger business plan requirements, climate resilience stress testing, metrics, deliverables, and accountability measures, although direct incentive strength will influence how resilience competes with other funded outputs.
Distribution resilience covers several overlapping risks. Networks must manage rising electrical demand, ageing assets, storm exposure, flooding, heat stress, wildfire risk, cyber threats, and changing load profiles caused by EVs, heat pumps, solar PV, batteries, and industrial electrification. Investment may include overhead line hardening, substation flood protection, automation, remote switching, vegetation management, undergrounding, mobile generation arrangements, control systems, and improved asset monitoring.
The transmission side of the investment cycle is already moving through large reinforcement proposals, including National Grid’s £4.5bn reinforcement funding request. ED3 is the distribution counterpart, focused on how local and regional networks fund capacity, reliability, and resilience without approving unnecessary expenditure ahead of proven need.
The planning challenge is a question of pace as much as scale. Distribution networks have to prepare ahead of demand, but the location and speed of electrification remain uncertain. Heat pump adoption, EV charging clusters, industrial connection requests, local generation, and data centre loads can emerge unevenly. If networks wait for constraints to become fully visible, connections and reliability can suffer. If they build too early, consumers may pay for assets before they are needed.
Flexibility can help manage that uncertainty, although it has limits. Demand response, storage, smart charging, and local flexibility procurement can release capacity or defer reinforcement, yet they cannot remove the need for physical assets where demand growth is sustained or resilience risk is structural. The ED3 settlement will need to distinguish between short-term flexibility value and long-term reinforcement need.
Financial incentives shape that balance. Direct incentives can encourage companies to prioritise resilience, but they must be designed carefully to avoid rewarding spending that would have happened anyway or encouraging excessive investment. Reputational incentives and deliverables can improve transparency, but may have less force where resilience competes with other funded outputs.
The next stage will be set through DNO business plans, which will need to combine engineering evidence, regional energy forecasts, flexibility assumptions, asset condition data, climate risk analysis, and deliverable investment programmes. ED3 will test whether Britain can expand local power networks at the pace electrification requires while maintaining reliability through more volatile operating conditions.
Ofgem’s ED3 consultation and decision documents are available from the RIIO-ED3 Sector Specific Methodology page.
