London's Tube has been running so long it's literally raising the temperature of the earth around it

By Jonn Elledge
Londoners swelter on the Central line during the heat wave of 2003. Image: Getty.

“Why is the tube so hot?” is one of those questions Londoners find themselves asking a lot during the three or four days a year when the city’s weather isn’t completely bloody miserable. But it’s not something to which I’ve ever given much thought. Lot of people, enclosed space – the reasons are obvious, surely?

Except, not every underground railway in the world has this problem. And once upon a time, London didn’t either: when the Bakerloo line first opened, posters suggested it was a good place to keep cool on a hot day, an idea that’s clearly nonsensical in 2017.

And then, from the Twitter feed of occasional CityMetric contributor @LeftOutside earlier*, I learned something genuinely amazing:

My mind, as the kids say, is blown.

And it’s true. In 1900, according to this fascinating article in Rail magazine, the ambient heat of the earth surrounding the tunnels – clay, mostly – was around 14°C. In the height of summer, the tunnels were indeed colder than the air above, so it made sense to travel by tube to cool down.

The problem is – trains full of people tend to give off heat. According to this article from a 2007 edition of Plant Engineering magazine, the vast majority (89 per cent) of that heat comes from the train itself (the friction during braking is the big one), 7 per cent from passengers and 4 per cent from “Tunnel support systems”.

What happens to this heat? On the sub-surface lines – basically, those which share tracks with the Circle – it’s not too big a problem. The tunnels are close to the surface, so often emerge into the light for brief periods (Barbican, South Kensington and Edgware Road are all above ground). They also have plenty of ventilation shafts. The heat has somewhere to go.

The deep tubes, though – the ones which are literally tunnels bored through the ground – are more problematic. Most of them are old, so were built before anyone realised heat would be a problem, and don’t come with enough ventilation shafts to solve it. The air is trapped. And so, the heat is absorbed by the walls, and the earth behind them.

In 1900, as noted above, the average ambient temperature was 14°C. Some 117 years and millions of trains later, it can be anywhere between 20°C and 25°C.

 Let’s just say that again: London has been running tube trains so long that the ground beneath parts of the city is now as much as 10°C hotter than it was in 1900.

One result of this is that the earth has become much less effective at absorbing the excess heat. That means the tunnels themselves have heated up, too. A lot: air inside them can often reach as high as 30°C. You’ve probably noticed this is you’ve been on the tube recently.

For the last decade or so, Transport for London has been looking for solutions to this. Some of them involve increasing the capacity of existing ventilation systems (lack of space above ground means it’s extremely difficult to build new ones). Others involve adding systems which circulate water to cool the air. Yet other options involve things like more efficient braking systems, on the grounds that if you put less heat in, you have less to take out.

Experimental air coolers on the Victoria line. Image: Oxyman/Wikipedia Commons.

It’s clear that there’s no easy solution, however: in 2003, then London mayor Ken Livingstone offered a prize of £100,000 to anyone who could come up with fresh ideas. Nobody could think of anything TfL wasn’t already trying, and the prize went unclaimed.

The upside to this story is that other cities have learned from London’s mistakes, and ensured that ventilation systems are an integral part of new metro systems.

The downside is you’re likely to boil every time you get the Central line in summer for the foreseeable future.

*LeftOutside has since been in touch to tell me he was summarising another article, from the Ian Visits blog. I haven’t read that one – the above article is drawn from the two articles I reference, plus some bits from TfL. But in the name of politeness and an easy life I'm acknowledging its existence and adding a link. Read that too, if you like. 

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and also has a Facebook page now for some reason. 

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Here’s a review of Kanye West’s new housing project, written by a professor of urban design

By Nick Dunn
A giant inflatable Kanye West. Image: Getty.

There is a long history of patrons for architecture, who have ensured their legacy – and often enhanced their status – through the construction of lavish buildings. Of course, some of these have been philanthropic figures, such as Andrew Carnegie, who supported the construction of more than 2,500 libraries around the world, or Oprah Winfrey, whose many charitable causes include building schools for children in developing countries.

More recently, Brad Pitt has taken an interest in architecture. His support for the construction of new homes in New Orleans – via his Make It Right foundation – following Hurricane Katrina has continued to keep social and environmental concerns in the public eye. Clearly, this is a worthwhile endeavour, and hard to fault.

Now entering the arena is Kanye West, who recently announced on Twitter that his company Yeezy would be branching out into architecture. Early visualisations of West’s collaboration with architects Jalil Peraza and Petra Kustrin and 3D artist Nejc Škufca suggest the first project will be a prefabricated concrete “low income” housing scheme, arguably designed in a Brutalist style.

Questions arise, perhaps not least regarding whether the self-proclaimed polymath genius is the right person to create social housing for the masses. As a professor of urban design, it’s not immediately clear to me how the competing forces of real estate, fame and social concerns can be remixed to blend harmoniously in the modern urban landscape.

Form over content?

By putting his weight behind this project, West has drawn much-needed attention to a critical issue in a society that, for many years, allowed housing to divide communities and determine social status. In the US, public housing projects are much maligned – sometimes referred to as “the housing of last resort”. If West wants to enhance the reputation of public or affordable housing as something residents can take pride in, then his intentions are admirable.

But with Kanye West, the message can always overtake the medium. With typical bombast he has said:

I’m going to be one of the biggest real-estate developers of all time – what Howard Hughes was to air crafts and what Henry Ford was to cars … We gonna develop cities.

Having purchased 300 acres of land to develop five properties, it certainly seems he is committed to the idea at some level.

It may be unhelpful, at some level, to criticise West’s motives – but we can and should question the potential outcome. As West told a group of Harvard students: “I really do believe that the world can be saved through design, and everything needs to actually be ‘architected’.”

On the plus side, this kind of vision along with West’s high level connections, considerable resources and sheer force of personality could enable this development to actually happen – which, since the demolition of the dilapidated and crime ridden Pruitt-Igoe project of St Louis, Missouri in 1973 further plunged the public view of mass housing into disrepute, is no small achievement.

Yet West is seemingly impervious to constructive criticism or capable of being managed – as he has even said himself. We can reasonably assume community engagement and participatory processes will go out of the window. These are essential for public housing, especially in the US where their omission has contributed to terrible living conditions.

In their place, his love for the people is expected to be met by the appreciation and gratitude of the masses. His embrace of disruption does not acknowledge the consequences – in a lot of cases, innovation fails to favour with people living on low incomes. In the context of urban design, putting in place infrastructure such as train tracks and highways has typically served to provide sharp boundaries between different communities.

Hashtag ignorance

Recent outbursts – such as his statement regarding slavery being a choice – have done little to display his ability to understand the very people the Yeezy Home is being designed for. Further, his unwillingness to grapple with the complexity of politics and racism endemic in US urban development only highlight how removed from history and society he actually is.

Megalomaniacs have produced many visions for cities over the years, with mixed results: consider the contrasting schemes of Swiss Modernist architect Le Corbusier or Hitler’s personal architect Albert Speer, in their respective quests for a new urbanism. The neo-Brutalist aesthetic of the Yeezy homes is a sideshow in this arena, an Instagram-ready shorthand for contemporary cool. The real story is the grand vision into which the housing sits.

With West’s drive to build his utopia on behalf of others, while skirting around inconvenient issues such as social equity, spatial justice (determined by access and proximity to essential services, public funds and other features) and urban history, his success will be immense – just not in the way he imagines it.

By designing for – rather than with – people, ignoring important social and urban developments and assuming the role of great benefactor, West would enter the history books – but not as a pioneer for social good or innovative design. Instead, he would join an already crowded history of urban developers who designed black people out of the landscape.

For this particular entanglement of social housing and celebrity endorsement, the future of the Yeezy Home project looks likely to aid and abet gentrification processes, not resolve them. Another brand for him, in the guise of a concern for the many –– and that’s the brutal truth.

Nick Dunn, Professor of Urban Design, Lancaster University.

This article was originally published on The Conversation. Read the original article.

 

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