TfL Ref: FOI-0876-1718
Thank you for your email received by us on 12 July 2017 asking for information about the temperature monitoring on the tube. Please accept my apologies for the delay in responding to you.
Your request has been considered in accordance with the requirements of the Environmental Information Regulations and our information access policy. I can confirm that we hold some of the information you require. You asked:
I should like to know what data has been obtained, and the method by which it has been obtained, and whether monitoring is continuing for:
Trains stabled at depots; Train during their passage during the day both underground and above ground (Both internal and external temperatures)
Underground Platform temperature's, running tunnel temperature's
Please provide the data outputs.
London Underground records temperatures across the Underground in order to inform our cooling initiatives.
Temperature monitoring within trains was undertaken on the Central and Victoria Lines in November 2008 and February/March 2009 as part of our Cooling the Tube programme. Central line monitoring was also undertaken in July 2015. The Victoria line rolling stock was replaced between July 2009 and June 2011 with the new 09 trains. These measurements are attached for your information.
The Cooling the Tube programme also undertook some thermal imaging of train surface temperatures. These images are attached for your information.
Platform temperatures on the deep Tube are routinely monitored using data loggers. Average monthly evening peak temperatures are provided in the attachment.
We are investing millions as part of a long-term programme to ensure we can deliver more services, and continue to introduce new trains to meet growing customer numbers whilst providing more comfortable journeys. We have implemented energy efficient solutions on new trains which saves energy and reduces the heat generated. We have also removed heat from our station and tunnel environment by installing new ventilation or cooling solutions.
On the Central line we have installed solar reflective material on the external surface of train roofs and solar reducing films on windows to minimise solar gains into the carriages.
On the Victoria line we have doubled the capacity of thirteen ventilation shafts which provide more air flow, as well as introduced regenerative braking (which returns power to the rails while the train is braking) on the new trains. We have also installed air cooling units and mechanical chillers at some key busy stations, such as Oxford Circus, and have been using groundwater underneath Victoria Tube station to provide cooling to the platforms. We are similarly using water from the aquifer underneath Green Park to provide cooling for that Tube station. In addition, we have upgraded existing ventilation fans and installed new fans at a number of stations across the network.
As part of this work to make customer journeys more comfortable, we are also working to reduce temperatures inside carriages. 192 new air-conditioned trains are now in operation on the Circle, District, Hammersmith & City and Metropolitan lines. We will be introducing 250 new Tube trains with air-cooled carriages on the Piccadilly, Bakerloo, Central and Waterloo & City lines, with the first new trains serving the Piccadilly line from 2023.
If this is not the information you are looking for, or if you are unable to access it for any reason, please do not hesitate to contact me.
Please see the attached information sheet for details of your right to appeal as well as information on copyright and what to do if you would like to re-use any of the information we have disclosed.
FOI Case Officer
FOI Case Management Team
Transport for London