Ofgem secures £20 million redress payments from National Grid Electricity Transmission after licence failures at Harker 132kV substation

National Grid Electricity Transmission plc (NGET) has today (Wednesday 11^th March 2026) agreed to pay £20 million into Ofgem’s Energy Industry Voluntary Redress Scheme after accepting historic failures to properly monitor, maintain and repair some civil assets and to plan and resource remediation works on those civil assets at the Harker 132kV substation near Carlisle, Cumbria (“Harker”) in the period November 2016 to November 2021. 

Harker serves customers in the Northwest, and there is embedded generation (including renewable generation) seeking to connect to the distribution network in the locality. The substation also connects to the 132kV transmission network in Scotland, making it part of the overall network capability across the Anglo-Scottish border.  

Ofgem’s investigation, launched in March 2022, concluded that NGET failed to take appropriate steps in relation to the condition of some civil assets at Harker and delayed the connection of some embedded generation in the locality. Specifically, NGET has accepted historic failures to: 

• adequately monitor, maintain and repair some civil (non-electrical) assets at Harker, allowing deterioration, including spalling concrete exposing steel reinforcement, to continue;
• operate a more formal and thorough inspection and risk assessment regime for those structures; and
• adequately plan repairs and source sufficient spare parts to carry out repairs on those civil assets, contributing to the cessation of upgrading works being undertaken at the same time that were necessary to fulfil a connection agreement

as required by Section 9(2) of the Electricity Act 1989 and Standard Licence Condition B7, which require transmission licence holders to: 

• Develop and maintain an efficient, co-ordinated and economical transmission system.
• Facilitate competition in electricity generation and supply.
• Ensure adequate resources to properly and efficiently operate the transmission business. 

NGET has already undertaken repairs to those civil assets at Harker in 2022 and acknowledged the failures set out above.  

Cathryn Scott, Regulatory Director of Market Oversight & Enforcement said:

“Delays and asset failures risk reliability issues, which ultimately impact consumers. This has been a complex and detailed investigation and it was concerning that NGET failed to adequately monitor, maintain and repair some civil assets at Harker 132kV substation during the period being investigated (November 2016 to November 2021). It is right that NGET has accepted its failings at this substation.”  

The Harker 132kV substation is being rebuilt and extended as part of the Harker Energy Enablement project to increase capacity between Scotland and England and prepare the network for future demand, including renewable and storage connections.  

Local investment programmes by National Grid and other networks (including 400kV and 132kV substation rebuilds) highlight Harker’s role in enabling cross-border power flows and clean energy integration.” 

Background

• The Energy Industry Voluntary Redress Scheme is operated independently by the Energy Saving Trust on behalf of Ofgem. It distributes voluntary payments from companies to energy-related projects that support vulnerable consumers, drive innovation, and reduce carbon emissions across Great Britain. As of July 2025, the scheme has allocated £181 million to 721 projects, supporting over 800,000 households. Redress funds are used when direct compensation cannot be appropriately targeted, ensuring money benefits consumers via charities and community organisations.
• Section 9(2) Electricity Act 1989 imposes a duty on transmission licensees to develop and maintain an efficient, co-ordinated and economical transmission system and to facilitate competition in the supply and generation of electricity.
• SLC B7 (Transmission Licence) contains an obligation that licensees have resources available at all times to properly and efficiently run its transmission business and to comply with its licence and statutory obligations.