Ofgem announced its final determinations of our Electricity Transmission business plan for the RIIO-2 regulatory period covering 2021 to 2026. Ofgem’s regulatory framework is known as RIIO (Revenue = Incentives + Innovation + Outputs). The RIIO model offers network companies incentives for innovation and securing investment, so they can develop sustainable energy networks at the lowest cost for current and future customers.
RIIO-T3 business plan (2026-2031)
Final determinations
Our RIIO-2 business plan (2021-2026)
Our Performance Summary
We publish a summary of our performance so that we can explain how we have performed to our customers, stakeholders and end-consumers. We hope that you find it useful and we welcome your feedback on how we can improve our report in the future.
Download Our Performance Summary
Regulatory Financial Performance Reporting (RFPR)
This is our Regulatory Financial Performance Reporting (RFPR) submission to Ofgem. RFPR contains our financial performance for 21/22 under the RIIO framework. RFPR enables Ofgem to administer the licence conditions that relate to the price control. This includes monitoring the performance of licensees against Final Determinations, monitoring compliance with price control obligations and reviewing performance between price controls.
View our Value for Money section for Regulatory Financial Performance Reporting
Penrhos - MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener approval to support investment at Penrhos to construct a new 132kV substation to connect two customers in Angelsey.
Necton - MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener approval to support investment to extend the Necton 400kV substation to connect three offshore windfarms in East Anglia.
Norwich - MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener approval to support investment to extend the Norwich Main 400kV substation to connect two offshore windfarms and one additional customer in East Anglia.
Marston Vale - MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener approval to support investment to build a new substation near Millbrook, Bedfordshire to connect the Millbrook power generation plant.
Pitsmoor - MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener approval to carry out essential works at the Pitsmoor substation to facilitate the integration of Northern Powergrid’s (NPG) asset replacement programme.
South Wales Pathfinders - MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener approval to support three NESO Pathfinder driven investments across South Wales.
Central Pathfinders - MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener approval to faciliate the connection of synchronous condensers at Walpole and Yaxley substations following a NESO pathfinder programme to enhance grid stability in the East of England.
Central Reactive Voltage Compliance - MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener approval to support the delivery of two new 200MWAr 400kV shunt reactors - one at the Ironbridge 400kV substation and one at the Willington East 400kV substation.
Operational Tripping Systems - MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener approval to support five Operational Tripping System investments across the network.
Pathfinder Sellindge - MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener approval to support investment in the South East to extend the Sellindge 400kV substation to enable a NESO driven Pathfinder investment .
Minety - MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener approval to support investment at Minety substation to improve network resilience in order to enable additional generation to the network in the South West.
Heysham OPS - MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener approval to upgrade and extend the existing protection and control systems at Heysham 132kV GSP in order to facilitate 130.5MW of embedded generation.
Wallend - MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener approval to support investment at Wallend to construct a new 400kV substation to connect new generation and interconnector customers in the South East.
Hylton Castle MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener funding to support investment to connection a private electrical network for the International Advanced Manufacturing Park (IAMP) in Sunderland.
Elland MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener funding to support investment at Elland 132kV Substation in West Yorkshire to provide a connection to existing busbars via a spare bay, enabling Northern Powergrid (NPg) to construct their generation bay equipment.
Willesden & Kensall Green Microsoft Data Centre MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener funding to support investment at Willesden 400kV & 66kV and Kensal Green 400kV substations (in the north of London to provide connection for Microsoft Cloud Infrastructure and Operations (MCIO) Limited
WISD6 Extension - SEPD MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener funding to support investment in the North of London to provide two additional 66kV connections for Southern Electric Power Distribution (SEPD)
Electricity System Operator: Pennine Pathfinders MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener funding to support investment to provide new shunt reactors connected to the 3 NGET sites in the North of England
- Stocksbridge 400kV
- Bradford West 275kV
- Stalybridge 400kV
Leiston MSIP
This submission seeks Medium Sized Investment Project (MSIP) reopener funding to support investment at Leiston 132kV substation in Suffolk for a new demand connection for the Sizewell C project.
Non-Operational IT Capex reopener – Data
This submission requests additional funding for an investment in the underlying digital technology which will provide NGETs stakeholders with simple, direct, and easy access to NGET data and insights. The objective of this submission will provide a way of making the best use of data and be more transparent through greater data access and improved platforms.
Pathfinders
This submission requests the approval by Ofgem of the Need Case for the additional allowances to provide new shunt reactors connected to the following National Grid Electricity Transmission’s (NGET) sites because of NGET being awarded the development, design and delivery works as an output from NGESO’s Network Options Assessment (NOA) High Voltage Pathfinder.
- Stocksbridge 400kV substation – 200 MVar Unit
- Bradford West 275kV substation – 100 MVar Unit
- Stalybridge 400kV substation – 200 MVar Unit
Leiston substation Customer Connection
This submission requests the approval by Ofgem of the Need Case for the additional allowances required to provide 2 x 132kV GIS Bays at Leiston 132kV Substation in Suffolk. The 0MW connection is to accommodate 2 x feeder circuits supplied to a new privately owned 132/11kV Substation to be called Old Abbey.
Bespoke: Tower Steelwork and Foundations (NGET) – ET Special Condition 3.33
The assets covered in this re-opener report are overhead line tower steelwork and foundations and are bespoke to ET Special Condition 3.33. This report develops the estimates provided in our RIIO-2 submission into a detailed investment request for:
- The volume of replacement steelwork which was originally based on high-level helicopter assessments.
- The volume of foundation remedial work which was originally based on assumed levels of intervention ahead of the outcomes of intrusive investigations (planned for RIIO-2).
SO:TO Optimisation Output Delivery Incentive
This report summarises the enhanced services delivered by National Grid Electricity Transmission (NGET) and the forecast constraint saving achieved in 2022/2023 financial year (FY23), which was the second year of the trial ODI.
Substation Civils Infrastructure Reopener
This submission outlines required RIIO-T2 expenditure of £58.07m in addition to initial funding of £25.45m previously granted. This funding will enable us to maintain the reliability of civil infrastructure at 186 sites across the Main Interconnected Transmission System.
Non-Operational IT Capex reopener
NGET’s redacted submission to the April 2021 Non-Operational IT Capex re-opener. This includes the main submission documents and supporting Annexes.
Lister Drive Customer Connection
This submission requests additional funding to provide a connection for Statkraft UK connecting to NGET’s Lister Drive 275kV substation following the output from National Grid Electricity System Operator Stability Pathfinder process that will allow Stakkraft to provide ancillary services to reduce constraint cost.
Frodsham 400kV Customer Connection
This submission requests additional funding to provide a connection for Mersey Reactive Power connecting to NGET’s Frodsham 400kV substation following the output from National Grid Electricity System Operator High Voltage Pathfinder process that will allow Mersey Reactive Power to provide ancillary services.
Cellarhead Customer Connection
This submission requests additional allowance to provide a 132kV connection at Cellarhead Grid Supply Point (GSP) in Staffordshire. The connection is to accommodate a feeder circuit connection between Whitfield Bulk Supply Point (BSP) and Cellarhead GSP being installed by Western Power Distribution (WPD), this will allow WPD to continue to operate a compliant network.
Melksham Operational Tripping Scheme (OTS) Phase 2
This submission requests additional allowance to extend the existing the Melksham Operational Tripping Scheme, this is driven by a range of future Generation Customers connecting into the South West region of England, These additional connections to the Transmission System would result in thermal, voltage and stability issues when particular double circuit unplanned outages occur during certain planned outages.
National electricity infrastructure protection from extreme weather
National Grid is seeking funding to deliver 33 additional weather protection projects in years 2 and 3 of RIIO-T2. This investment will protect assets and sites most at risk from surface water flooding, which has increased due to climate change. An additional reopener is also expected in 2023 to cover the remaining sites which require protection during RIIO-T2.
SF6 Asset Investment to prevent carbon emissions
National Grid requires funding within this regulatory period (T2), to deliver interventions at electricity infrastructure sites that already have or are predicted to have significant SF6 leakage. SF6 gas is used as an insulating medium used in electricity network assets and is 23,500 times more potent than Carbon Dioxide as a greenhouse gas. This investment is forecast to prevent 500,000 tonnes of carbon emissions until 2030, which is the equivalent of planting more than 8 million trees.
RIIO-2 Statutory Licence Consultation
We responded to Ofgem’s RIIO-2 Statutory Licence Consultation. This response was on behalf of National Grid Electricity Transmission plc (NGET) and National Grid Gas plc (NGGT). You can read the following response documentation:
Download the following Annexes
- Annex Chapter 1-9 of the Special Conditions
- Annex Special Conditions being removed
- Annex Standard and Special Conditions being modified
- Annex PCFH
- Annex PCFM.
National Grid Electricity Transmission Independent User Group
We are the Independent User Group responsible for scrutinising National Grid’s RIIO 2 business plan and challenging how they engage with stakeholders. As the Independent User Group, we represent a cross-section of the energy industry and beyond, bringing our individual expertise and experience across a broad range of energy issues.
National Grid Electricity Transmission Independent User Group
RIIO-2 Stakeholder Engagement
We are working to improve our stakeholder engagement – and that is why we place community relations at the heart of our infrastructure projects.
Read stakeholder engagement case studies
Redaction Explanatory Statement
Document published in accordance with the RIIO-2 Re-Opener Guidance and Application Requirements Document.
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