London Power Tunnels 2 (LPT2), lined throughout with Shay Murtagh's precast tunnel segments, is National Grid's £1bn scheme to rewire South London's electricity network. The project replaces ageing high voltage cable routes with 32.5km of new tunnel running between Wimbledon and Hurst across seven London boroughs. Delivered by the Hochtief Murphy Joint Venture (HMJV) and designed by Aecom, it buries the new cables in tunnels 3m in diameter, sited between 30m and 50m underground with a 120 year design life, giving National Grid a resilient network built to meet the capital's growing electricity demand for generations to come.
Shay Murtagh was appointed to supply the precast tunnel segments for the entirety of the 32.5km route, produced using equipment supplied by Herrenknecht Formwork Technology. Every ring was manufactured to the tight tolerances demanded by the project's four tunnel boring machines, quality controlled through our Integrated Management System and delivered to site by our own logistics and transport teams, keeping pace with a programme that bored 20km of tunnel in a single year.
Tunnelling on LPT2 ran from 2020 to October 2023, when the final TBM, Grace, broke through at Eltham having driven over 11km from New Cross. The works moved 900,000 tonnes of excavated material, with 99.98% diverted from landfill, and needed eight vertical shafts up to 55m deep for construction access and, later, maintenance. Operating under the ICE's Project 13 Enterprise model, HMJV and its supply chain had to hit a tight schedule while meeting National Grid's sustainability targets on one of the UK's biggest utilities infrastructure programmes, a balance recognised when LPT2 was named Utility Project of the Year at the 2024 British Construction Industry Awards.
With tunnelling and lining complete, work has moved on to installing 200km of high voltage cable and building the headhouses that will give safe access to the tunnels once they are live. A third transmission circuit between New Cross and Hurst was energised in December 2025, with the full scheme due to be operational in 2026, bringing the new routes into service and strengthening electricity supply for homes and businesses across South London.
As the sole supplier of tunnel segments across all 32.5km of LPT2, Shay Murtagh's role sits at the heart of one of the UK's most significant energy infrastructure projects of the past decade. It builds on our track record on major tunnelling schemes featured across our projects, and reflects the scale of work our production and logistics teams are set up to deliver. Contact us to talk through the tunnel segments needed for your next project.
