Tunnel vision

Midnight, early summer. Mid-1990s. Jiten Patel and three friends are testing a rumour. They’ve been told by a friend in the know that beneath the South Kensington campus lies a vast network of secret tunnels, enabling access to almost any part of the campus. And apparently there’s a way in – if you know where to look. “It seemed absurd that you could go through a hatch and walk under all the buildings, but we decided to investigate,” Patel (Physics 1999) recalls. 

The group met at their designated rendezvous and waited for the coast to clear. They located the access point and entered the tunnels – grimy, dark but surprisingly spacious; filled with control panels, junction boxes and hot pipes that carried steam and water to heat the campus. While Patel focused on not getting lost, one of the group tried to record the layout into a map – but soon ran out of space. “We must have been in there for four or five hours,” he says. “At one point we found a stepladder and poked our heads out of the middle of Exhibition Road with a car coming towards us.” 

Patel and his fellow explorers had discovered Imperial’s service tunnels, which although now inaccessible, date back to the 1851 Great Exhibition. Filled with wires, cables and pipes, the tunnels contain water, data, phone, security and power and extend under the entire campus and are believed to have once connected to the basements of the nearby museums. Extremely hot, the tunnels are nevertheless surprisingly well lit and tidy. 

Among students in the know, myriad rumours have arisen: they were used to store radioactive waste; they were the locations for love trysts (a makeshift bed and empty bottle of wine were once discovered in one tunnel) or drinking clubs; they were protected by armed guards. 

Actually, there’s the faintest ring of truth to that last claim. Alun Kimber (Chemical Engineering and Chemical Technology 1982) was a student at Imperial in 1980, when the nearby Iranian Embassy on Princes Gate was stormed by gunmen. Kimber was in his student accommodation watching the snooker in the TV lounge when it was interrupted by a live broadcast from the siege. He and friends decided to get a closer look via the tunnels, as the police had closed the conventional route onto the main road. 

“You just needed to know the right door and then you were in,” he says. “We followed this guy through these musty brick tunnels and popped up very close to the back of the embassy. It was on fire as the SAS had just gone in and a policeman saw us and came running towards us telling us to get inside.” Kimber and co rapidly retreated into the nearest safe building. “What I found strange at the time was that the policeman didn’t know what was going on – although I since realise that the SAS would have taken full control, including communication.” 

“We essentially operate our own power and heat network here. We generate the heat centrally and then distribute it around the campus from the Energy Centre. We have our large tunnel network to distribute heat and power through the buildings. If you visit a similar sort of campus like a large hospital, you will see all the pipes above ground – we are able to store it all under the streets. It is very discreet and out of sight.” 

The project makes significant carbon savings of around 2,400 tonnes a year. Caldwell is proud of the efficiency of the two gas-fired combined heat and power engines, from which waste heat generated by the exhaust is captured and fed into the boilers, where it is turned into water to heat the buildings. The three new boilers are replacing three steam boilers that, after 25 years’ service, had reached the end of their lifespan. At the same time, the water pipe network – which carries about 132,000 litres round the campus – is being increased in size to take the additional heat load. Heating units in the plant rooms beneath each individual building are also being upgraded. In the handful of places where steam is still needed – for autoclaves or steam sterilisers, for example – it is now generated locally. 

As the Energy Centre comes back online in December, the changes will make for far greater environmental and economic efficiencies. The financial savings that Imperial receives from generating its own electricity are already substantial, but Caldwell believes even more can be done in conjunction with net zero planning that is in development. “I am now looking at the next phase of the project, which is going back to grassroots and reducing demand,” he says. 

“I believe that rather than creating innovative new ways to generate heat, we should reduce the need in the first place. There are a lot of huge and complex research projects that go on in our buildings and these require a lot of heat and a lot of power – but there can be a lot of waste that goes along with that. We are seeking the most efficient and optimised solutions for these buildings.”