Distribution Network Options Assessment (DNOA)
The Distribution Network Options Assessment (DNOA) Methodology is a framework designed to explore all options, including flexibility, to meet capacity needs and to deliver a reduction of up to £410 million in load-related expenditure during RIIO-ED2 in a transparent manner. The DNOA suite of documents is published annually and provides transparency to the industry on the decisions we are making across our South East, London and East of England regions
In our DNOA process, we identify future capacity needs based on the latest predictions from our Distribution Future Energy Scenarios (DFES). We then source all the viable options to resolve our system needs, compare them and make a recommendation for the optimal solution. This work combines information from multiple publicly shared databases and is explained in the methodology document.
The information provided will inform our stakeholders, such as Flexibility Providers (FPs), Local Authorities, Ofgem, the Department for Energy Security and Net Zero and other interested parties about developments on our network, presenting upcoming opportunities to participate in the flexibility market, providing transparency to policy makers about our internal governance and facilitating other stakeholders’ development plans towards Net Zero.
The Distribution Network Options Assessment (DNOA) Methodology is a framework designed to explore all options, including flexibility, to meet capacity needs and to deliver a reduction of up to £410 million in load-related expenditure during RIIO-ED2 in a transparent manner. The DNOA suite of documents is published annually and provides transparency to the industry on the decisions we are making across our South East, London and East of England regions
In our DNOA process, we identify future capacity needs based on the latest predictions from our Distribution Future Energy Scenarios (DFES). We then source all the viable options to resolve our system needs, compare them and make a recommendation for the optimal solution. This work combines information from multiple publicly shared databases and is explained in the methodology document.
The information provided will inform our stakeholders, such as Flexibility Providers (FPs), Local Authorities, Ofgem, the Department for Energy Security and Net Zero and other interested parties about developments on our network, presenting upcoming opportunities to participate in the flexibility market, providing transparency to policy makers about our internal governance and facilitating other stakeholders’ development plans towards Net Zero.
DNOA March 2026
We began developing the 2026 DNOA recommendations in October 2025 after we produced updated load growth forecasts. We identified system constraints and therefore flexibility requirements for flexibility tender round 13 (TR13), which took place between December 2025 and January 2026. Notably, this tender round featured several changes compared to previous years: most notably we shortened the tender period to cover only the remaining two years of the current regulatory cycle, RIIO-ED2, instead of the customary three years. We will continue to adapt our processes as use cases for flexibility evolve and widen for ED3.
Another key change in TR13 involves discontinuing tenders for substations equipped with single transformers. These substations typically experience 24-hour constraint windows, which the flexibility market cannot address effectively for technical and commercial reasons. Consequently, we no longer tender for these sites.
In December 2025, we produced updated forecasts that reflected UKPN’s inputs as part of the National Energy System Operator’s transitional Regional Energy Strategic Plan (tRESP) process and used them to award flexibility contracts and finalise the DNOA recommendations. The tRESP process and new consistent planning assumptions notably influenced our load growth forecasts. We also once again integrated high-confidence local insights into our best-view forecast.
DNOA March 2026
We began developing the 2026 DNOA recommendations in October 2025 after we produced updated load growth forecasts. We identified system constraints and therefore flexibility requirements for flexibility tender round 13 (TR13), which took place between December 2025 and January 2026. Notably, this tender round featured several changes compared to previous years: most notably we shortened the tender period to cover only the remaining two years of the current regulatory cycle, RIIO-ED2, instead of the customary three years. We will continue to adapt our processes as use cases for flexibility evolve and widen for ED3.
Another key change in TR13 involves discontinuing tenders for substations equipped with single transformers. These substations typically experience 24-hour constraint windows, which the flexibility market cannot address effectively for technical and commercial reasons. Consequently, we no longer tender for these sites.
In December 2025, we produced updated forecasts that reflected UKPN’s inputs as part of the National Energy System Operator’s transitional Regional Energy Strategic Plan (tRESP) process and used them to award flexibility contracts and finalise the DNOA recommendations. The tRESP process and new consistent planning assumptions notably influenced our load growth forecasts. We also once again integrated high-confidence local insights into our best-view forecast.
Long term system needs
We are publishing alongside the DNOA reports, full lists of sites where we will consider investment decisions out to 2050 to give greater transparency of our system needs. This list will be regularly updated going forwards.
Below you will find links to download the latest DNOA publication documents.
Long term system needs
We are publishing alongside the DNOA reports, full lists of sites where we will consider investment decisions out to 2050 to give greater transparency of our system needs. This list will be regularly updated going forwards.
Below you will find links to download the latest DNOA publication documents.