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Beneath our feet: London’s energy tunnels

We've all been looking up to the North for infrastructure innovation. Next, we might be looking down

By Prospect Team  

This article was produced in association with National Grid

One of the biggest projects in London is going on beneath the city’s streets. National Grid is investing £1bn on its London Power Tunnels project, to put 32kms of electricity cables under the city. Emma FitzGerald, Director of National Grid’s UK gas distribution network, explains the scale of the work. “The geographic scope of that is to the west, Willesden, to the east, Hackney. Up to Kensal Green in the north and down to Wimbledon. That’s the area that is covered by London Tunnels. In a sort of a T-shape.”

“That is high voltage cable. And that’s geared towards forecasts we’ve made about energy requirements for the city. We expect that energy demand is going to go up by 4 per cent a year to 2020 and therefore that upgrade is needed.”

The company is also planning a large-scale gas upgrade for the capital—it has plans to spend a further £1bn on replacing 1,800 miles of pipe, a huge challenge. Much of London’s gas pipework was put in during Victorian times.

“In some instances, they haven’t been touched since,” says FitzGerald.

“If you put those two things together then we have a key role in supporting the infrastructure bill for Boris, to help him meet some of his ambitions. The numbers he talks about in his London infrastructure board activity, which I am part of, is that the population of London right now is 8.7m, and that’s expected to grow to 10m by 2030. Population growth combined with the increase in electric vehicles, infrastructure developments such as Crossrail and the electrification of domestic heating, are some of the factors driving this demand.”

The investment being made by National Grid is part of a larger programme of investment in rail and water infrastructure, which is being coordinated by the Mayor’s office.

“A big part of our job, with the other infrastructure builders, is to do our infrastructure development efficiently in reaction to changing energy needs. This includes things like ensuring that we are working together to minimise disruption to the public by sharing holes in the road” she says. “We have to replace 1,800 miles of pipe—we are using robotic technology to try and do that in a way that we don’t have to dig a hole and disrupt a street.” The use of such new methods has meant that so far National Grid has been able to save close to 3,000 working days meaning less disruption and less of a need to pass costs onto customers.

The London Power Tunnels idea was generated by National Grid, and approved by Ofgem, the energy regulator. National Grid made it clear to Ofgem that substantial work was required in London. Tunnelling is due to finish in March and the cables will be energised in 2018.

The improvements to London’s gas infrastructure will be more noticeable than the electricity upgrade, but FitzGerald says that National Grid is used to dealing with the sorts of problems that might arise. Though much of the work will be subterranean, the look of London will also be changed. The old gas-storage towers, familiar landmarks across much of the city, will go.

“They are already out of the system,” she says. “All of the gas holders built to store town gas are no longer needed, so we’ve gone through a demolition process.” National Grid will use some of the sites for property development and expects that as many as 10,000 new homes will be built on the reclaimed land.

“Doing this kind of work in London puts you under huge scrutiny in terms of planning requirements, local authority legislation, liaison with Transport for London and the Mayor’s office. It’s a very complex environment,” says FitzGerald, who adds that other cities will require similarly extensive work, albeit on a smaller scale.

“Looking at the way that George Osborne is talking about Manchester,” she says, “I would imagine that that might be the place that you might look next.”

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