Ice blocks to cool the Tube

The plan is to pass the train’s air supply over blocks of ice located beneath the train’s seats to cool the carriages. The solution is being considered for the Piccadilly Line.

The scheme has been proposed because conventional air conditioning cannot be used in Tube tunnels because it would further increase temperatures.

Under the system being developed for the Piccadilly Line, the ice store will be charged when the train is on the surface. Once inside the tunnels, the refrigeration plant will be switched off, enabling ice alone to cool the carriage air supply. When the train re-surfaces, the refrigeration units will switch on to re-freeze the store.

Trials of the system will take place next year as one of a series of initiatives to make Tube travel more comfortable.