Any Londoner will tell you that the Underground can be hellishly hot. Now, a joint project between Islington Council, Transport for London (TfL) and engineering firm Ramboll, aims to put that heat to good use by heating homes in the London borough of Islington.
The initiative will see warm air from the Northern Line, the oldest deep-level metro line in the world, heat 1,350 homes, offices and leisure centres in the borough.
A heat pump will capture “waste heat” from a ventilation shaft in a long-abandoned tube station on City Road, which currently pumps out air at 18C to 28C (64F to 82F).
Ramboll says that their feasibility study confirmed that this source of waste heat could be exploited by heat pumps, which would capture the waste heat and upgrade it to approximately 80 degrees Celsius.
TfL said it could be a “significant low-carbon energy source”.
The project is the second phase of Islington’s new Bunhill Energy Centre which already keeps about 700 new homes warm.
The Greater London Authority (GLA) estimates that there is enough heat wasted in London to meet 38% of the city’s heating demand. With the expansion of district heating networks, this could rise to 63% of demand by 2050.
“We believe that the use of large-scale heat in this way connected to urban district heating systems will play a major part in decarbonising the UK’s heating energy demand”, says Lucy Padfield, Director District Heating at Ramboll.
“The use of heat pumps utilising industrial waste heat sources is more carbon efficient than gas-fired CHP, the usual source of heat for district energy schemes. I am convinced that with the increasing use of renewable power sources, large-scale heat pumps connected to district heating systems will play a major role in the future heating of cities in the UK.”
Islington council is hoping that as well as reducing carbon emissions, the initiative will also reduce heating costs for residents living in the borough.
Another advantage is that the stifling heat on certain underground lines should be reduced, leaving the environment cooler for travellers.