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Haven’t been on the Central, but if it’s warmer than the Victoria Line…OMG. I was only on the Victoria line for two stops this evening, but that was more Than enough. Northern line felt like it had Aircon in comparison.
Central line is so much worse even from the perspective that unless you are going literally one stop you are likely to be spending more time on it than the victoria line
Love that place, have a whole stack. Always beautiful artwork :) me and my wife make the most unlikely of train spotters but the facts she spews amaze me. The Acton depot does an open day i think four times a year and it’s a great day out.
They also used to do one in the summers saying how much cooler it was below ground.
But over the years the tunnels have trapped so much heat mainly from the train motors and braking. That the surrounding clay can't absorb any more heat.
Edit:typos
Yeh it is warmer below. You’d of thought ventilation pipes would be easy enough to fit. Hindsight is a wonderful thing.
Or a giant ice cube on every train. And I’m not on about the rapper.
A lot of the routes follow that of main roads. IIRC because back in the 1800s and early 1900s. They couldn't knock down the buildings on either side of the road. But they could close the road for a few months in sections and have a diversion. As they dug down, installed the tunnel and then back filled the hole (cut and cover). Which worked on the shallow lines. Which usually have more ventilation shafts. On the deep lines, it was proper tunneling all of the way. And kind of hard to know exactly where you were in relation to the surface. Not to mention that when the Victorians were building them, that their fans weren't exactly brilliant and once they went to electric trains there was little need for them. The very first trains were steam powered and need far more ventilation.
>A lot of the routes follow that of main roads.
Yes, but not quite because of what you suggest.
> IIRC because back in the 1800s and early 1900s. They couldn't knock down the buildings on either side of the road. But they could close the road for a few months in sections and have a diversion. As they dug down, installed the tunnel and then back filled the hole (cut and cover). Which worked on the shallow lines. Which usually have more ventilation shafts.
The sub-surface lines are indeed like that because of the reason you say - the Metropolitan, District, and Hammersmith & City lines are all like this; they also have the air-conditioned S-stock trains because of this extra space. And, as you said, these lines were also steam loco operated when they opened, so more space and ventilation was required. (There's also the well-known Leinster Gardens, where a house was demolished to make way for the Underground, and then a false façade put up to hide the gap!)
> On the deep lines, it was proper tunnelling all of the way. And kind of hard to know exactly where you were in relation to the surface.
A lot of the early deep-level lines follow roads for much of their routes - look at the routes of the Northern and Central lines - despite not being cut-and-cover construction. These are so because of two things - firstly, it was unsure as to what effect the tunnels would have to the buildings above them, but also because the ownership of land extended beneath the buildings and so it was cheaper as the railways didn't have to pay as much for the land as they would have had (or, indeed, where) they built under buildings.
That ice cube idea reminds me of the time when I was freezing cold in my house as a child and I tried lighting candles to warm myself up. I lit up dozens of them.
Yep, I wrote my masters dissertation on the feasibility of using it as a heat source with heat pumps, cooling the tube and heating London (in the winter obviously).
That was one of my references/case studies!
They use the heat from the ventilation shaft to basically drive an air source heat pump with very high efficiency because it's warm air, mine was looking at using ground source bore holes drilled outwards from the tunnels themselves like a hedgehog to draw heat from the clay and lower it's temperature to allow it to become more of a heat sink again.
>Temperatures on the Underground have slowly increased as the clay around the tunnels has warmed up; in the early days of the Underground it was advertised as a place to keep cool on hot days. However, over time the temperature has slowly risen as the heat sink formed by the clay has reached its thermal capacity. When the tunnels were built the clay temperature was around 14 °C (57 °F); this has now risen to 19–26 °C (66–79 °F) and air temperatures in the tunnels now reach as high as 30 °C (86 °F).
https://en.wikipedia.org/wiki/London_Underground_cooling#%3A%7E%3Atext%3DTemperatures_on_the_Underground_have%2Chas_reached_its_thermal_capacity.?wprov=sfla1
What I don’t understand is why they don’t have aircon on the trains which work above ground but turns off when it gets into tunnelled sections.
As it stands, the reason given for not using aircon is due to the heat it generates in tunnels, which can’t dissipate, and I understand that. But more of the Underground is above ground than under and the trains are still sweatboxes in the above ground sections.
The Picadilly line also has a few sections around Earls Court where it comes into daylight and then back into a tunnel. Jubilee line around Canary Wharf comes up and down a few times.
It would cool down the interior, cool down the body temperatures of those who stay on throughout, which will have an impact beyond the underground sections.
I hadn't thought about the power draw.
I used to live in Dublin, come from Belfast, and would travel between the two cities by rail regularly. The carriages drew power from the engine which provided motor power. What would inevitably happen would be that the train would be parked in Belfast on Dublin on a hot day, or a dark night, and the lights would be blaring and air con chilling, which led to the engine frequently idling at quite a high rev while stationary. This led to the engines being overworked and quite a high incidence of breakdowns. Ultimately they ended up buying separate generator engine vans to provide electric to the carriages.
Fair, here it’s mostly so the 4th rail supply won’t get overexerted, as it could cause a massive power outage for the network, especially with older and clunkier AC units. They couldn’t fit it to even the 1995 Stock, which was built at a fairly high spec to last a long time, because AC wasn’t feasible in the 1990s to fit to a London Underground unit.
Even mainline 3rd rail railways couldn’t use it until power supply was upgraded (a major change that was made to allow the Electrostars and Desiros to operate in the 2000s), hence why air con remained mostly on diesel stock like class 158s, and on OHLE powered stock like class 91 hauled mk4 carriages, as the OHLE could already supply enough power usually.
They did consider it in the original plan for the Victoria Line 2009 Stock, as well as walk through carriages, and LED displays with disruption information, effectively giving you the same experience as the Elizabeth Line class 345s, but in a smaller train, as by then the technology had made it much more plausible. This was scaled back significantly however, largely due to the Financial Crisis, and the final product basically gives the same experience to a passenger as the 1995 or 1996 Stock.
The S Stock did get the AC and walk through carriages, as the effects of the crisis had subsided a bit, and it was much easier on larger units. We’re expected to basically get the package originally promised for the 2009 Stock in the 2024 Stock on the Piccadilly Line too, as it has become even easier, because the equipment is a lot more efficient
As with every investment, when others have a greater incidence of extreme stimuli, it becomes easier to justify the investment. Like why Heathrow shuts down for weather that JFK doesn't.
> What I don’t understand is why they don’t have aircon on the trains which work above ground but turns off when it gets into tunnelled sections.
>
>
>
> As it stands, the reason given for not using aircon is due to the heat it generates in tunnels, which can’t dissipate, and I understand that. But more of the Underground is above ground than under and the trains are still sweatboxes in the above ground sections.
Yeah you're not wrong really. The new Pic Line trains starting at the end of next year will all have air conditioning though, not sure if it's gonna run continuously through the tunnels too though. The new trains generate less heat so maybe they decided they can run the AC the entire time without causing the tunnels and platforms to get warmer than now.
But yeah either way like you said even if the AC only ran on the above ground sections it should still make the trains much cooler in the tunnels if it's turned off during those parts, at least for the lines not underground long in 1 stretch like Central and Jubilee which are only 30ish mins. Pic Line is more like 40 mins though so it would get warm. Northern is probably longer. Victorias permenently underground. DLR is getting air con this year with new trains but that's almost fully above ground.
Yup. The Islington Bunhill Heat and Power project uses that heat to power/heat around 1000 homes. If it was replicated heat in the system would be removed and a better temperature could be maintained.
To be fair, TFL has done a pretty damn good job already, yeah prices are high for the tube but it’s a good service, at least compared to national trains.
There was a design which I think was trialled briefly.
At the line terminuses which are well outside central London and above ground, large blocks of ice were made and loaded on the trains. These provided Aircon by blowing air over them, but also generated no extra heat in the underground which is a requirement for all the older areas which don't have good ventilation built in and all deep tube lines. The ice blocks were swapped for new ones at the terminus when they'd mostly melted.
The heat in the tube lines (deep tunnels) is above the surrounding rock temperatures because it builds up heat given off by the trains, and it won't dissipate through the rock fast enough, so it is slowly climbing in temperature.
I think the Victoria line was the first line where they actually included significant design specific to improving the underground ventilation for cooling. One of the London Underground Museum tours takes you through one of the new Victoria line tunnels which was built just for ventilation.
Avoid if you can; packed in like sardines. CO2 emissions pouring out into the upper streets and traffic forced to travel on A routes blamed for pollution. Guess you younger people are going be forced onto a bicycle. Glad I no longer have to travel underground.
From Glasgow, and was bigging up London to Mrs. Finally went and experienced underground, never seen such a grey soulless place, people literally looked like their souls had been lost. London life is hard for most.
# Upvote/Downvote reminder Like this image or appreciate it being posted? Upvote it and show it some love! Don't like it? Just downvote and move on. *Upvoting or downvoting images it the best way to control what you see on your feed and what gets to the top of the subreddit* *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/london) if you have any questions or concerns.*
Can confirm. The central line is fucking hell on earth.
Haven’t been on the Central, but if it’s warmer than the Victoria Line…OMG. I was only on the Victoria line for two stops this evening, but that was more Than enough. Northern line felt like it had Aircon in comparison.
You’ve never been on the central line?
I don’t live here regularly so I can’t remember the last time I was on the central line when it is hot
You probably passed out, possibly had a heatstroke and don’t remember a thing
Free sauna with every ride on the central line
awww that's cute... is it warmer than the Victoria line? bless your heart
The Piccadilly line is no joke at this time of year!
Central line is so much worse even from the perspective that unless you are going literally one stop you are likely to be spending more time on it than the victoria line
>The central line is fucking hell on earth. 😂😂😂
That is so cool. I’d love a print of this
London Transport Museum sells them, as well as the "It's cooler below" variant for summer.
How the tables have turned
I have this and a whole bunch of the vintage posters as fridge magnets, I love them.
Love that place, have a whole stack. Always beautiful artwork :) me and my wife make the most unlikely of train spotters but the facts she spews amaze me. The Acton depot does an open day i think four times a year and it’s a great day out.
The Underground is a beacon in good visual design from beginning to end.
I love the current "hold the handrail" posters.
They also used to do one in the summers saying how much cooler it was below ground. But over the years the tunnels have trapped so much heat mainly from the train motors and braking. That the surrounding clay can't absorb any more heat. Edit:typos
Yeh it is warmer below. You’d of thought ventilation pipes would be easy enough to fit. Hindsight is a wonderful thing. Or a giant ice cube on every train. And I’m not on about the rapper.
A lot of the routes follow that of main roads. IIRC because back in the 1800s and early 1900s. They couldn't knock down the buildings on either side of the road. But they could close the road for a few months in sections and have a diversion. As they dug down, installed the tunnel and then back filled the hole (cut and cover). Which worked on the shallow lines. Which usually have more ventilation shafts. On the deep lines, it was proper tunneling all of the way. And kind of hard to know exactly where you were in relation to the surface. Not to mention that when the Victorians were building them, that their fans weren't exactly brilliant and once they went to electric trains there was little need for them. The very first trains were steam powered and need far more ventilation.
>A lot of the routes follow that of main roads. Yes, but not quite because of what you suggest. > IIRC because back in the 1800s and early 1900s. They couldn't knock down the buildings on either side of the road. But they could close the road for a few months in sections and have a diversion. As they dug down, installed the tunnel and then back filled the hole (cut and cover). Which worked on the shallow lines. Which usually have more ventilation shafts. The sub-surface lines are indeed like that because of the reason you say - the Metropolitan, District, and Hammersmith & City lines are all like this; they also have the air-conditioned S-stock trains because of this extra space. And, as you said, these lines were also steam loco operated when they opened, so more space and ventilation was required. (There's also the well-known Leinster Gardens, where a house was demolished to make way for the Underground, and then a false façade put up to hide the gap!) > On the deep lines, it was proper tunnelling all of the way. And kind of hard to know exactly where you were in relation to the surface. A lot of the early deep-level lines follow roads for much of their routes - look at the routes of the Northern and Central lines - despite not being cut-and-cover construction. These are so because of two things - firstly, it was unsure as to what effect the tunnels would have to the buildings above them, but also because the ownership of land extended beneath the buildings and so it was cheaper as the railways didn't have to pay as much for the land as they would have had (or, indeed, where) they built under buildings.
How would you even start to wrap an ice cube?
What do I look like, an ice cube engineer? I’d probably just leave it, the heat the underground puts out by the time it melts it will just evaporate
That ice cube idea reminds me of the time when I was freezing cold in my house as a child and I tried lighting candles to warm myself up. I lit up dozens of them.
Did it work?
Is there any truth to this? The clay bit?
Yep, I wrote my masters dissertation on the feasibility of using it as a heat source with heat pumps, cooling the tube and heating London (in the winter obviously).
Don't leave us hanging, how's the feasibility?
Technically yes, practically not so much!
Love your username lol
Look up Bunhill 2, it's been put into practice once... https://www.islington.media/news/bunhill-2-launch-pr
That was one of my references/case studies! They use the heat from the ventilation shaft to basically drive an air source heat pump with very high efficiency because it's warm air, mine was looking at using ground source bore holes drilled outwards from the tunnels themselves like a hedgehog to draw heat from the clay and lower it's temperature to allow it to become more of a heat sink again.
Sounds like a fascinating idea
>Temperatures on the Underground have slowly increased as the clay around the tunnels has warmed up; in the early days of the Underground it was advertised as a place to keep cool on hot days. However, over time the temperature has slowly risen as the heat sink formed by the clay has reached its thermal capacity. When the tunnels were built the clay temperature was around 14 °C (57 °F); this has now risen to 19–26 °C (66–79 °F) and air temperatures in the tunnels now reach as high as 30 °C (86 °F). https://en.wikipedia.org/wiki/London_Underground_cooling#%3A%7E%3Atext%3DTemperatures_on_the_Underground_have%2Chas_reached_its_thermal_capacity.?wprov=sfla1
Wow, that’s so interesting! Thanks for the information, I’ll add that to my fun facts.
What I don’t understand is why they don’t have aircon on the trains which work above ground but turns off when it gets into tunnelled sections. As it stands, the reason given for not using aircon is due to the heat it generates in tunnels, which can’t dissipate, and I understand that. But more of the Underground is above ground than under and the trains are still sweatboxes in the above ground sections. The Picadilly line also has a few sections around Earls Court where it comes into daylight and then back into a tunnel. Jubilee line around Canary Wharf comes up and down a few times. It would cool down the interior, cool down the body temperatures of those who stay on throughout, which will have an impact beyond the underground sections.
Part of it is just that a lot of the stock was made before that was feasible, and the power draw was still a big issue
I hadn't thought about the power draw. I used to live in Dublin, come from Belfast, and would travel between the two cities by rail regularly. The carriages drew power from the engine which provided motor power. What would inevitably happen would be that the train would be parked in Belfast on Dublin on a hot day, or a dark night, and the lights would be blaring and air con chilling, which led to the engine frequently idling at quite a high rev while stationary. This led to the engines being overworked and quite a high incidence of breakdowns. Ultimately they ended up buying separate generator engine vans to provide electric to the carriages.
Fair, here it’s mostly so the 4th rail supply won’t get overexerted, as it could cause a massive power outage for the network, especially with older and clunkier AC units. They couldn’t fit it to even the 1995 Stock, which was built at a fairly high spec to last a long time, because AC wasn’t feasible in the 1990s to fit to a London Underground unit. Even mainline 3rd rail railways couldn’t use it until power supply was upgraded (a major change that was made to allow the Electrostars and Desiros to operate in the 2000s), hence why air con remained mostly on diesel stock like class 158s, and on OHLE powered stock like class 91 hauled mk4 carriages, as the OHLE could already supply enough power usually. They did consider it in the original plan for the Victoria Line 2009 Stock, as well as walk through carriages, and LED displays with disruption information, effectively giving you the same experience as the Elizabeth Line class 345s, but in a smaller train, as by then the technology had made it much more plausible. This was scaled back significantly however, largely due to the Financial Crisis, and the final product basically gives the same experience to a passenger as the 1995 or 1996 Stock. The S Stock did get the AC and walk through carriages, as the effects of the crisis had subsided a bit, and it was much easier on larger units. We’re expected to basically get the package originally promised for the 2009 Stock in the 2024 Stock on the Piccadilly Line too, as it has become even easier, because the equipment is a lot more efficient
Also underground train systems in other countries can have aircon in tunneled sessions, but TFL isn't going to invest in actually making any upgrades
As with every investment, when others have a greater incidence of extreme stimuli, it becomes easier to justify the investment. Like why Heathrow shuts down for weather that JFK doesn't.
> What I don’t understand is why they don’t have aircon on the trains which work above ground but turns off when it gets into tunnelled sections. > > > > As it stands, the reason given for not using aircon is due to the heat it generates in tunnels, which can’t dissipate, and I understand that. But more of the Underground is above ground than under and the trains are still sweatboxes in the above ground sections. Yeah you're not wrong really. The new Pic Line trains starting at the end of next year will all have air conditioning though, not sure if it's gonna run continuously through the tunnels too though. The new trains generate less heat so maybe they decided they can run the AC the entire time without causing the tunnels and platforms to get warmer than now. But yeah either way like you said even if the AC only ran on the above ground sections it should still make the trains much cooler in the tunnels if it's turned off during those parts, at least for the lines not underground long in 1 stretch like Central and Jubilee which are only 30ish mins. Pic Line is more like 40 mins though so it would get warm. Northern is probably longer. Victorias permenently underground. DLR is getting air con this year with new trains but that's almost fully above ground.
The earths core is about 5,200° Celsius. Seems accurate.
I love the insinuation that the tube is warmer because it's closer to the Earth's core.
Yup. The Islington Bunhill Heat and Power project uses that heat to power/heat around 1000 homes. If it was replicated heat in the system would be removed and a better temperature could be maintained.
Very interesting project. Thanks for citing it. Looks like TFL don’t have the budget for more sites anymore but they are tendering it out.
To be fair, TFL has done a pretty damn good job already, yeah prices are high for the tube but it’s a good service, at least compared to national trains.
They didn't specify that the "below" is where the Central Line runs
Some times it's a bit too warm though
That's fantastic, I love it.
I have this on my wall, right next to the "it's cooler below" poster
Yup... this was accurate today
Definetly aged well
Very fitting that they used the Spanish flag to illustrate it, the Central line is hotter than Almería in the mid of August.
Central line is cheap sauna session
There was a design which I think was trialled briefly. At the line terminuses which are well outside central London and above ground, large blocks of ice were made and loaded on the trains. These provided Aircon by blowing air over them, but also generated no extra heat in the underground which is a requirement for all the older areas which don't have good ventilation built in and all deep tube lines. The ice blocks were swapped for new ones at the terminus when they'd mostly melted. The heat in the tube lines (deep tunnels) is above the surrounding rock temperatures because it builds up heat given off by the trains, and it won't dissipate through the rock fast enough, so it is slowly climbing in temperature. I think the Victoria line was the first line where they actually included significant design specific to improving the underground ventilation for cooling. One of the London Underground Museum tours takes you through one of the new Victoria line tunnels which was built just for ventilation.
Cold 🥶 and rain ☔️ and fog 🌫️, oh my!!! Roll on autumn 🍂.
Bioshock vibes
Avoid if you can; packed in like sardines. CO2 emissions pouring out into the upper streets and traffic forced to travel on A routes blamed for pollution. Guess you younger people are going be forced onto a bicycle. Glad I no longer have to travel underground.
From Glasgow, and was bigging up London to Mrs. Finally went and experienced underground, never seen such a grey soulless place, people literally looked like their souls had been lost. London life is hard for most.