210 x 297mm

September 2014

TRANSMISSION

CAPITALDELIVERYLondonPower Tunnels

In February 2011, National Grid

embarked upon a seven-year, £1 billion

project to rewire the capital. The

project uses deep underground tunnels

in order to minimise disruption while

facilitating on-going maintenance and

providing long-term flexibility.

Procurement efficiencies and strong

project management have encouraged

innovation and should bring the project

in ahead of schedule and 5–10%

under budget.

RE REORGANISING NEGOTIATING

REENGINEERING

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Complex engineering challenge in a densely

populated area

Innovative solutions providing environmental

benefits

Strong performance management of multiple

contractual arrangements

Proactive stakeholder and community

outreach

210 x 297mm

London Power Tunnels

Project map

Awards

Complex tunnelling operations

Innovative solutions

Transformers

Ventilation

New, smaller transformers with water cooling reduce

substation footprint

Land developed into social and privately owned housing

Waste energy used to heat local school

Dynamic system modelling takes into account cooling effect

of the tunnel linings

Power supply size reduced and control system reduces

occasions when fans are run

Waste and spoil removal

Mining technology used to remove spoil from tunnels

Spoil used to fill legacy gas holder sites, reducing both

disposal and site remediation costs

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International Tunnelling Awards 2012:

International Tunnelling Awards 2013:

Brownfield Briefing Award 2012:

Safety Initiatives Award

Sustainability Award

Best Re-use of Materials

Existing Substation

Phase 1 cable route

Existing cable route

Other existing routes

New Substation