Innovative fan chiller technology helps Tube passengers keep cool
Passengers using St Paul's Tube station are being kept cool this summer by an innovative fan chiller system, which pumps cold air onto the eastbound Central line platform.
At the heart of the new system - a first for the Tube network and designed and built by LU's cooling team - is a ventilation fan which pulls fresh air in from the street.
The air is then cooled by a water chiller system which circulates 16 litres of cold water every second around the pipes in the ventilation shaft, cooling the air by up to seven degrees before it is blown onto the platform.
The huge fan is capable of moving the equivalent of 15 double-decker buses full of air every minute.
New Tube for London
In the past it has been challenging to lower the temperature on the Central line as traditional cooling systems have proved prohibitively expensive and difficult to install within the 115 year old tunnels and stations. The New Tube for London will bring the first walk-through air-cooled trains on to the deep-level Tube network - which includes the Central line - with the first trains due to be introduced in the 2020s.
Until then, LU continues to seek innovative solutions to reducing temperatures during the summer months on the deep-level lines. Other measures currently aimed at cooling the Tube include:
- New air conditioned trains on the Metropolitan, Circle and Hammersmith & City lines, with 40% of the network covered by 2016
- The capacity of the station ventilation fan network has been doubled and 83 fans restored
- Portable fans installed within ticket and concourse areas, to increase air circulation at a number of stations
- The creation of a Cooling Innovation Centre to explore new efficient and environmentally friendly methods to cool the Tube
Big engineering challenge
David Waboso, LU's Capital Programmes Director, said: 'We know travelling around London during the summer months can be uncomfortable which is why we are always looking for innovative ways to tackle the temperature.
'Cooling the Tube is a big engineering challenge, but we're making significant steps forward and, by the end of 2016, 40% of the Underground network will be served by air conditioned trains.
'Projects like the installation of a fan chiller system at St Paul's Tube station demonstrate how LU has some of the most skilled, creative people in the business when it comes to developing entirely new ways to cool London's Tube.'
In addition, a larger fan chiller system is being installed this summer at a mid-tunnel ventilation shaft on the Victoria line between Walthamstow Central and Blackhorse Road Tube stations.
The work is being done to coincide with the period of major improvement works on the Victoria line this month which will enable the operation of 36 trains per hour next year.
The new fan chiller system will be ready for next summer and mean more comfortable temperatures for passengers at the northern end of the Victoria line.
LU's cooling team is developing proposals to continue the expansion of this innovative technology in the coming years.
Notes to Editors:
- New air conditioned trains have been introduced on the Metropolitan, Circle and Hammersmith & City lines and are currently being introduced on the District line. The 191 new trains will cover 40% of the Tube network by 2016
- In 2008 portable fans were installed within ticket and concourse areas, to increase air circulation at a number of stations. A further six fans have been installed this year to expand this successful scheme
- LU is establishing a Cooling Innovation Centre to explore new efficient and environmentally friendly methods to Cool the Tube. The ground-breaking research undertaken at this centre, which will be supported by world leading academics from London South Bank University (LSBU), will assist LU in delivering its £300 million programme of investment in cooling infrastructure over the next 10 years
- LU is working to upgrade the existing station ventilation fan network. 83 ventilation fans have now been restored, more than doubling the capacity of the fan network. It is also in the process of introducing a network-wide cooling control system to remotely monitor the performance of cooling assets. This system will drive increasing availability of its cooling systems, in turn reducing temperatures on the network
- Mechanical chiller units, which provide cooling to customers and staff in the ticket hall area, have now been installed at Oxford Circus and Euston Tube stations
- Two of London's busiest Tube stations, Green Park and Oxford Circus, were upgraded in 2012 with the installation of air cooling units that reduce temperatures at platform level. At Green Park, the air cooling units use cool water extracted via boreholes from the aquifer deep below Green Park
- At Oxford Circus station the successful air cooling scheme was expanded to include all platforms (Bakerloo, Central and Victoria lines). The new platform cooling units use cool water provided by chiller units that have been installed adjacent to the station
- LU has installed high speed ceiling mounted impulse fans on Bakerloo line platforms at Marylebone and Lambeth North Tube stations