The London Underground hasn’t received any new vehicles with climate controls for more than nine years, and it could be decades until the system is ready for today’s summer temperatures.
Many trains operating on the Piccadilly line of the London Underground have now been in service since 1973. A time when, freak heatwave aside, the UK was blessed with more predictable and less extreme weather patterns.
This week it was announced that a new fleet would be introduced on the service with air conditioning, the first time this luxury has been included in carriages running on the deep-level lines that make up 60% of the subway network. The news comes after thermometers hit over 35C in the capital last month. Below-surface, the Central line claimed the unfortunate title of Hottest Tube Line, reaching 39.4C.
Until relatively recently, the Underground has struggled to incorporate air conditioning due to the compact size of infrastructure compared with other systems in comparable cities. Many of which were designed and built later, and often with a pre-existing need to function properly in high temperatures. The Elizabeth line bucks the trend as the only truly modern part of the Tube network, and unsurprisingly remained a relatively manageable 22C during June’s blistering heatwave.
Siemens has now developed a solution using significantly smaller air conditioning devices that fit beneath Tube carriages, although even this hit serious problems during testing meaning plans to introduce the first units in December 2025 were delayed until this winter. Other orders are set to be made for similar updates to vehicles on the Bakerloo line — with trains dating back to 1972 — and Central and Waterloo & City Lines, where current rolling stock was first introduced in 1992.
However, funding is another obstacle that looks more difficult to overcome than the challenge of actually fitting equipment onto vehicles. At the time of writing, no orders have been made for any lines other than Piccadilly services due to a shortfall in finance. This means analysts expect it to be decades before the entire system has air-conditioned trains, emphasising Britain’s lack of preparedness when it comes to the impact of rising temperatures on vital transport infrastructure.
Image: Pau Casals / Unsplash
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