In February 2011, National Grid embarked upon a seven-year, £1bn project, to rewire the capital via deep underground tunnels, in order to meet increasing electricity demand and help London access the renewable energy of the future.
In total 32km of tunnels have been constructed deep below the road network, which carry high voltage electricity cables.
LPT infographic
Most of the electricity supply in London is transmitted through underground cables, traditionally found just below the road surface. Work to maintain them is carried out at street level and can be disruptive.
By housing new electricity cables in deep underground tunnels, there are a number of benefits:
  • Less disruption during construction
  • Less disruption for maintenance and repairs
  • Future repairs and maintenance work can be carried out without disrupting traffic, residents and businesses
  • Additional cables can be installed in tunnels to meet future demand
In March 2015, tunnelling was finally completed on the project with the final breakthrough occurring at Kensal Green in North West London.
This landmark event marked the conclusion of four years of digging beneath the capital on a project which will help to secure London’s energy supply for the twenty-first century.
Following this, our efforts focussed on installing over 200km of high voltage cables in the tunnels, which provide the power needed to meet London’s growing electricity demand.
In February 2016 the project reached a major milestone, when the first section of this new high voltage cable was energised. Stretching from our brand new substation at Kensal Green to our existing substations at Willesden and St John’s Wood, the cables provide the power supply for the new Crossrail project.
The official opening of the London Power Tunnels project is taking place in February 2018.