Cooler underground, warmer homes

Anyone who has visited our London office recently will have been struck by the huge amounts of construction being carried out in our neighbourhood. Much of this comprises new social housing on the old primary school site and over-looked by the dominant 150m residential tower of City Forum by Foster & Partners. Moreland Street, on which our office is located, is mid-way into a traffic calming scheme that will result a more pedestrian-friendly environment and at the junction of Moreland and City Road, an extraordinary steel frame structure containing orange and brown containers is taking shape. Of all the works in our neighbourhood, this in my view is the most interesting. The structure is an important new component of the local district heating and cooling scheme and is known as the Bunhill 2 Energy Centre. Its purpose is simple; to draw the waste heat from the Northern Line underground tunnels and to use this the heat water that will circulate through the district heating scheme. The project has been developed by Islington Council with Transport for London and relies on what remains of an abandoned Underground station, namely City Road Station. Anyone who ever sat on a bus, crawling through the traffic of City Road, will have noticed this landmark.

This air shaft was all that remained of the City Road Station, after it’s brief life as a passenger stop on the Northern Line. The station was opened in 1901 but suffered from low passenger numbers and when modernisation of the network, driven by the need to run larger trains, began it was not considered viable to invest in City Road. The station closed in 1922, being re-purposed as an air raid shelter during the second world war. The station hall actually survived until the 1960s (see picture below) when it was substantially demolished, leaving the lift and stair shaft as City Road’s prime site for fly posting.

The Bunhill 2 Energy Centre now occupies this same site and uses the original turn-of-the-century shaft as the air shaft through which the waste heat is drawn. It’s a fascinating joining together of 21st century technology and early 20th century infrastructure. This huge heat pump will also feed cool air into the Northern Line which hopefully will help alleviate the over-heating and discomfort for which this line is well-known.

Sadly for those of us who have become rather fond of the bold orange ‘oil-rig’ aesthetic, this magnificent piece of technology will be covered by a semi-transparent metal screen on completion.