Laing O’Rourke and Murphy Selected for Major National Grid Upgrade
Laing O’Rourke and the Hochtief-Murphy joint venture have been awarded significant contracts for the National Grid's North West London Upgrade, aimed at enhancing electricity transmission capacity for new data centres.
Major Contracts Awarded for National Grid Upgrade
Laing O’Rourke and the Hochtief-Murphy joint venture (HMJV) have secured key contracts for the National Grid's North West London Upgrade project. This significant initiative, valued at £1 billion, aims to bolster the electricity transmission network across Bedfordshire, Hertfordshire, and North West London.
Project Overview
The North West London Upgrade will span from the Sundon substation in Bedfordshire to St John’s Wood in London. It is designed to accommodate the electricity demands of five new data centres, collectively requiring a total of 1 gigawatt (GW) of power. As part of this effort, Laing O’Rourke will focus on upgrading substations at three critical locations:
- Letchmore Heath
- Elstree
- St John’s Wood
Meanwhile, HMJV will be responsible for installing new 400kV cables and enhancing the existing transmission tunnel between Elstree and St John’s Wood.
Key Suppliers and Technologies
The project will also see collaboration with several notable suppliers. Hyundai Electric has been contracted to supply and install essential electrical equipment, including transformers. Siemens Energy will provide shunt reactors specifically for the Elstree substation, which is a crucial component in managing the electrical load and ensuring stability in the network.
Additionally, the construction of a 132kV gas insulated switchgear substation at Letchmore Heath is planned, further enhancing the infrastructure's capacity and reliability.
Broader Implications for the UK Electricity Network
This upgrade forms part of a larger £59 billion programme initiated by the National Grid to modernise the UK’s electricity transmission network. In August 2025, contracts worth £12 billion were finalised for civil works related to high voltage direct current (HVDC) projects, indicating a significant investment in the future of the UK’s energy infrastructure.
The National Grid has also established the Great Grid Partnership, appointing seven companies—including Laing O’Rourke and Murphy—to support various electricity infrastructure projects, including those connecting the grid to new offshore wind farms. This partnership reflects a comprehensive approach to enhancing the UK's energy capabilities and sustainability.
Conclusion
The collaboration between Laing O’Rourke and the Hochtief-Murphy joint venture is a crucial step towards meeting the increasing energy demands of modern data centres while simultaneously upgrading the existing infrastructure. As the UK moves towards a greener future, such projects will play a pivotal role in ensuring a reliable and efficient electricity supply.