Comments so far are not discussing what makes this light rail “very” light, so here’s an excerpt. The project claims to cost half of “normal” light rail.
> The vehicle is battery-powered, eliminating the need for overhead wires. It features an innovative turning system, enabling it to handle 15m radius curves. This allows for installation in tight corners within the existing highway. The Council intends for it to operate at a high frequency, providing a turn-up-and-go service. The vehicle has a capacity of 56, is comfortable and has low floors to enable passengers to embark and disembark easily. The vehicle has been developed to allow autonomous operation in future.
> The new track is laid just 30cm within the road’s surface, minimising the need to relocate pipes and cables, which is time-consuming and expensive. It achieves this by leveraging cutting-edge materials science, while still utilising standard rail parts to ensure ease of manufacture.
A 15 meter turning radius is tight, but not revolutionary. San Francisco's MUNI system's tightest turns are 45 feet, or 13.7 meters. The newer vehicles are designed for that, and the old PCC cars had to be modified to allow the trucks some extra rotation. The turning loop on Embarcadero near Market is that tight. There is much wheel screeching when a PCC car goes through that loop, because wheels have to slip to turn that tight. But it works.[1]
Battery powered trams have real potential, now that batteries with 5 to 7 minute charging and large numbers of charging cycles are a thing. That's compatible with typical end of line holding times. Steel wheel on steel rail is low friction, and you get most of the energy used to go uphill back when you go downhill. This could work out.
Overhead power is more efficient and sustainable though. No batteries to chug along, no batteries to replace or manufacture. And I wonder if the cost over time really makes up for hanging a few overhead lines.
> Steel wheel on steel rail is low friction, and you get most of the energy used to go uphill back when you go downhill.
If you were going up and down hills, would you still use steel wheel in steel rail unless you had some sort of cable to work with? I always thought the Muni did relatively level routes for that reason? The Lausanne m2 for example uses rubber (well, ideally you’d be able to just balance the train going up with the train going down, but that only works for simple inclines with limited stops). Actually, a battery powered rubber wheeled tram service on some sort of steep incline like SF’s cable car routes could get some wicked regen going down.
Even if level, they could still get some regen from making stops.
> A 15 meter turning radius is tight, but not revolutionary. San Francisco's MUNI system's tightest turns are 45 feet, or 13.7 meters.
Revolutionary as the turning circle will be used at speed with passengers to traverse roundabouts in-lane. CVLR doesn't need turning loops, as the vehicles can be driven from either end.
It’s fairly obviously designed to avoid the issues which almost caused the cancellation of the new Edinburgh tram — spiralling costs caused by the need to move existing utilities under the deep track base. That crisis was probably as much to do with a badly formed set of contracts as with the technical issues themselves, but it’s still worth designing out.
Avoiding relocating utilities is only really a stopgap until the utilities reach end of life at which point you would be ripping up the newly installed trackbed during the middle of its life.
At least in the US utility relocation also generally involves moving what was underneath to the side, so it can be accessed without disrupting the new transit line.
If you want a real tram that is compatible with existing street geometries, the really nice Škoda ForCity Smart Artic tram was developed to meet the requirements in Helsinki, which wanted a smooth modern tram even though there are 15m radius curves and 8% inclines in the old parts of the network. https://en.wikipedia.org/wiki/%C5%A0koda_Artic
These things are tiny! I've traveled in larger airport shuttles.
It feels like that's putting this into a really awkward place in the tradeoff space. Trams work because they can scale higher than buses. That scale comes at the cost of more up-front infrastructure, much less flexibility, and needing dedicated lanes. So cities don't have trams everywhere, but they're only installed on routes that can support the scale.
For these you still have the up-front investment (just less of it) and inflexibility, but don't get the efficiencies of scale due to how small the capacity is.
Is this really just a bet that they can get autonomous tram-driving on city street approved a decade+ sooner than autonomous buses?
Trans don’t need dedicated lanes, not sure where you got that idea from. Trains do.
Buses however are slow (in London about the same as walking) and (outside London) prone to vanishing on timetable changes. Closing a rail link is tricky, you can be confident that if you live near a tram stop it will be there in 10 years. 60% of our local (say 10 mile radius) buses have been removed in the last decade, removing entire villages from service.
A rail solution allows you to read, a bus throws you around everywhere and makes you sick.
Tiny might make sense if they are running every 2 minutes and thus getting their capacity via frequency. However there is no reason to think they will do that. (if they were running anywhere near that frequent overhead wire would be a lot cheaper than a battery on every tram)
I'd assumed the point of them was that you can take the several cars of a tram and split them up to have more frequent services. Though I suppose this would compound with the cost of having a driver on each car, potentially cancelling some of the gains from cheap installation. As for the point of automation, I think the tram can probably be a lot easier than the bus because of the human factor. It seems safer, so legislators will be more willing to legalise it and residents less likely to complain. Also, you've got rails in the road that clearly mark the route of the tram which make it more visible than an automated bus. Most of these automated taxi companies still have a human supervising the process, and I imagine that could be employed here to good effect and with fewer or faster manual interventions than would otherwise be needed.
Even if all that falls through, I'm not gonna complain about it. We sorely need more public infrastructure in the UK. Even if an experiment like this fails, at least you actually get a tram line and experience out of it. Much better than a project which sucks up million then gets cancelled. (Cough cough HS2.)
Buses on dedicated lanes are OK indeed. However, buses are simply not as comfortable as trams: roads unless in tiptop shape are not as smooth as rail, and bus drivers always take corners too fast.
Having to hold on to something discards it from my preferred list of solutions.
Trams can share lanes with normal car traffic. There's still a massive cost in terms of infrastructure (especially the overhead lines, utilities that need to get out of the way for the rail base, that sort of thing), but this project has a detailed description of why those aren't a problem for this project.
The tram they show in the animation also very much has a driver in the front.
If they can deliver on what they show in their demos, I don't see why the size of the trams or the infrastructure should be a problem. All the expensive stuff has been thought about, the system barely takes up any extra space, and the system is capable of scaling up by just sending more vehicles into service.
Trams don't actually scale higher than busses; the highest ridership BRTs have far more ridership than the highest ridership light rail. The key thing that makes it work is having a dedicated right of way. I expect busses get a bad rap as a scaled transit solution mostly because they have to share the roads so often. But it's indeed an advantage of light rail that it's a lot harder to make that mistake with it.
Buses have slightly lower capex but much higher opex from the perspective of the community. City street gets ripped up by buses, cyclists get caught under the bus and dragged for miles, children get asthma from the tire dust. It being easier to give trams priority at traffic lights and easier to make the tram autonomous are just added bonuses.
Lower flexibility is actually a feature when it comes to mass transit: People will build density along rail lines because they assume the town won't rip them up, making the rail line more valuable over time. A bus route can be cancelled the day after a disruptive mayor is voted into office.
I also don't see why you can't scale up the tram with additional cars, as long as you keep the lbs/sqft the same. 3 car trams are fine, 3 car busses are... not
Have recently read Gareth Dennis’ How Railways will fix the Future…
It’s a worthwhile read BTW
I suspect these are too small to carry a significant number of passengers per hour
They’ll also probably never be autonomous as the challenge with autonomous is less the driving and more with passengers getting on and off, getting trapped etc
This is such a typical American sneer at public transport.
It's tiny, how it possibly carry all those 2x4s, powertools and sheets of plywood when I'm out doing manly things. I'd better go buy that monster truck so I can look like a real man.
Trams are one example of Light Rail, but so is the Docklands Light Railway in London (an exception to "on sight" - it's automatic), as opposed the the Tube (underground) which is Heavy. But the Welsh "metro" project's "tram-trains" (Stadler Citylink) are also Light, even though their tracks into the valleys are very much not urban in the usual sense - the full valleys journeys are over one hour with the current trains and go through mostly rural areas with small towns.
Eliminating "the need" for overhead wires seems like a terrible trade off when you're adding "the need" for expensive batteries and charging infrastructure.
Besançon in France is one of the cheapest conventional tram schemes in Europe at €17.5m per km and €1.81 per tram (132 passengers). It’s a conventional tram track with overhead catenary wires: as standard as one can get with those things. Presumably in the UK the costs would be somewhat higher: France is a modern tram capital, with a lot of relevant talent and expertise available locally.
I haven’t found the projected figures for Coventry but it would be very, very awkward if they can’t beat the numbers above with a supposedly much cheaper track.
CVLR is projected to cost £10 MM per km, but we all know what projections are worth.
Still, there's no point comparing build costs between France and the UK as they're completely different cultures and jurisdictions. Instead, a more reasonable approach is to compare to recent similar project in the UK.
Edinburgh's tram covers 18.5 km and cost at least (they're still uncovering overruns years later) £1 BN. That's ~£50 MM or ~€60 MM per km. That's what CVLR should and will be benchmarked against.
Very good point. There’s also a potential for future upgrades. They may invest into catenary lines at some point, get rid of batteries and increase capacity inside vehicles. Or, switch to hot-swap batteries and increase vehicle turnaround and frequency. Or, they can switch to traditional concrete reinforcement for rails for future lines if they decide that the rails-on-slabs approach doesn’t work out as well as they hoped for. Their vehicles while custom-built are running on top of standard tram lanes, so they will be able to use traditional tram tracks, too.
VLRT seems gimmicky at first but the more I look at it the more sense it makes.
Manchester's Metrolink should also be used as a benchmark.
The Airport line extension cost £368m with 15 stops over 14.5km of track (which shakes out at roughly £25m/km), and was completed more than a year ahead of schedule and under budget.
> they're completely different cultures and jurisdictions
Separated by huge distance of 20 miles, both have thousands of same EU laws )still on the books,
share thousands of years of history and at one point ruled by the same aristocracy.
Everything old is new again: The Light Railways Act of 1896 also propsed rail lines built to less then mainline standards (often narrow gauge) to get transport links to otherwise unconnected locations. https://en.wikipedia.org/wiki/Light_Railways_Act_1896 comment edited because I fat finger editing the submit button
They're using "Standard rail components, innovative construction" - standard gauge rail, but laid over a foundation of slab ultra-high performance concrete (UHPC), which allows for the shallower foundation / avoidance of utilities relocation.
Using UHPC to rethink infrastructure is the big story here, I think.
It's not smaller than most of the buses that run in the existing Stagecoach and National Express fleets that go around and to and from Coventry, which seat approximately 30 people on a single-decker with standing room for about 10 more (in the best case, with no push-chairs, trolleys, or wheelchairs).
Important background:
Building the same tram in Britain costs at least 2X more than in France, often 3x more.
UK tram track construction typically involves deeper track beds compared to France/EU, using concrete slabs of 500-1000mm deep, is intended to protect utilities. In contrast, many European projects utilize shallower trackbeds, even with grassed areas, which are 300-400mm deep
Gadgetbahn - a derisive term transit advocates use for something that claims to be innovative but in fact doesn't do anything not thought of before and doesn't solve any problems.
They make all kinds of claims that don't stand up to over 100 years of history running trains. The claim they are innovative, but there is nothing new here, and no evidence they have looked at the real problems of transit systems. Someone is going to make a lot of money on this at the expense of the community that loses.
Trains have been around for a long time. You can buy all the parts you need for a good system off the shelf. You won't be saving money by designing something new, you just waste money on engineers to design something and then lose the scale factors you could get from buying the same thing as everyone else. If you buy the same thing as everyone else that means there will be a market for spare parts and thus in 20 years when (not if!) something breaks you can keep the system running.
Yes overhead wires are expensive - but they are a rounding error compared to track. Batteries are expensive too, and you have to buy a lot of them. Batteries need to be recharged which means these trams will be out of service often so they have to buy a lot more so that when one is out of service for charging the others can work. (you still need a few extra for maintenance, but battery charging is more common so you need a lot more)
If you want to build a train the best way to save money is to build exactly the same as everyone else does: standard off the shelf trains, running on standard off the shelf rails, and standard off the shelf overhead rail. If you want to innovate make sure that everyone is fluent in Spanish, Turkish, Korean, or Italian - because places where those languages are spoke build and run trains much cheaper than other places you can think of so you want to learn from them. (note that French or Japanese are not on the above list - while those areas do cheaper than English speakers, they are still expensive)
I'm not sure about the UK, but in the US most of the cost blowout for trains seems to be in stations, so focus all your innovation there: don't make them monuments to how much money you can spend. (The UK has cost problems almost as bad as the US, but I'm not aware of any study on where the issues come from, while at least in the US there are studies).
Well the standard response to this kind of "do it the way everyone does it" is "... change has to start somewhere". It's hard to tell, without hearing a report from a council of open-minded-rigorous-experts, whether some claimed innovation on a particular is actually worth doing or not---but certainly neither of "innovation is always good" and "innovation never works" is true.
Anyway everyone is pretty sure that that something is wrong with the standard train economics as you describe them, because if there wasn't something wrong with it there'd be a lot more trains. I can't tell from the site, or from your comment, if this is the solution, or even worth doing as an experiment... but "don't change anything ever" doesn't strike me as productive either.
The problems with trains are well known and they are not addressing them. There might be unknown problems an well, but the things they are talking about have already been tried and failed for reasons they don't seem to be aware of.
Innovation should require some knowlegde of what is already done - otherwise you invent square wheels.
You’re talking about trains, but this is about trams. The design constraints of building into an existing and very dense road network are complex.
I agree with much of your sentiment, and hope that the Coventry council is being challenged in these sorts of ways, but at the same time I recognise that each city is going to have quite different requirements for trams driving down the roads in its centre.
Perhaps a better push back is: why isn’t this just a better bus network?
You’re grossly oversimplifying and ignoring knock on effects.
Eliminating overhead wires isn’t about cost. It’s about being able to build in existing urban areas that don’t want high voltage live wires everywhere, and likely already have above ground infrastructure they would interfere with.
Unfortunately the Coventry VLRT is all about aesthetics over actually transit benefits. If the they were concerned about being useful transit the vehicle would have capacity higher than an articulated bus. Instead the main benefit of Trams/LRT over buses, capacity, is sacrificed leaving no real benefits. You can see the same thing with the Obama ere streetcars in the USA where most of them proved no real benefits over the buses the run alongside them but at least they retained the capacity even if it was never needed.
London’s DLR is a gadgetbahn. For all its obvious limitations it’s been quite successful. Lots of new stations, lots of expansions, decent integration with traditional rail. VLR would work similarly.
Finding the right balance of capacity is a tough problem because cities generally intend to grow, and it's expensive to to have unused capacity. As well if you actually build for that, people will say the project is a failure since ridership will seem low.
> If you want to build a train the best way to save money is to build exactly the same as everyone else does: standard off the shelf trains, running on standard off the shelf rails, and standard off the shelf overhead rail.
You are speaking like a naive person that thinks that most the challenge is the physical world
But in UK most of the challenge is archaic and idiosyncratic laws, disproportionately powerful NIMBY’s and the treasury brain.
The treasury brain will approve a project with 1X capex and 10x opex instead of one that has 2X capex and 1X opex
The NYMBY is wild and unpredictable, they just killed project for a data centre placed on top of a literal dump because it would ruin the view of that dump from a motorway (nobody lives there)
A project to re-open 3 miles of railway that already exists took 5 years to approve and 80,000 pages of environmental accessment
But if it’s innovate and designed in UK it might just slip through
In Australia, highest cost is buying up required land and construction of buildings. We spent ~100mil USD on a single, open air platform for a line extension of exactly that one station. It was about 5 km of extra track. It is amazing we have any trains at all.
Never heard of him until now. Looks interesting but I don't have tine for anouther hour long podcast in my life... I suspect he is drawing on similer sources as me - there are many other transit advocates saying what I am in greater detail.
If overhead wires were the only advantage of light rail, why is anyone using light rail instead of trolleybuses?
The answer is of course that rails provide major advantages on their own, primarily by allowing vehicles to travel much more efficiently thanks to the low friction of running steel wheels on steel tracks
“Thanks to the very low friction between the steel wheel and steel rail, railways can move a load using as little as 15% of the energy that road haulage needs.”
Everyone proposing trams says this. None of them provide any numbers. How much more efficient does it have to be to offset the much greater cost of the roadway?
It does make the name kinda ironic, since the batteries will make the tram heavier then a normal one that's powered by overhead wires, so its not 'very light'
There's various possible reasons. Less pollution from tire wear and the possibility to lay tracks across grass to create relatively ecological dedicated lines so the carriages don't get stuck in traffic are two options that spring to mind immediately.
For me, trams have a much more comfortable ride. The lack of pitch and roll reduces a lot of motion sickness and the rails are obviously a lot smoother than paved surfaces.
There’s nothing stopping a road from being smooth but, logistically, there’s clearly no reason to rush to repair roads when they deteriorate. That means potholes get tolerated, potholes means suspension, and both of those mean bus-like rides instead of suburban light rail rides.
Railway track has to be flat. Anything less than perfect is intolerable so it tends to hold its maintainers to a higher bar.
As I understand it tracks do a much better job of spreading the load than asphalt which makes it much more durable.
I've found the new battery buses to be far more comfortable to ride in than older diesel buses since they remove the vibration when idling. The extra weight might mean more potholes to repair though.
One advantage is that light rail encourages transit oriented development.
The fact that buses are so flexible and easily (and cheaply) rerouted makes developers less likely to build developments that rely on access to transit, but once a community spends a hundreds of millions of dollars on a light rail line, they know it's there for the long term.
There's been a ton of research on this and the conclusion has been that light rail does indeed attract more development than bus rapid transit, but that there is no net gain in development across an urban area. It just shifts development to the corridor in question. There's a reason the overwhelming majority of transportation engineers favor bus rapid transit. On the other hand, I personally prefer to ride in light rail and I think many people would agree. So there's a reason that many urban planners prefer light rail.
That's sort of the popular wisdom, but rails don't guarantee it will be there for the long run. DC recently announced that they're replacing their light rail with buses:
I agree with him that in order to endure and justify a permanent operating subsidy a transit service needs to be useful and used by many people. Most American light rail doesn't meet that bar.
I've seen that claim, but places that run good bus service for decades see plenty of transit oriented development. (most of those places also have subways though. The other options seems to bad bus service which won't get transit oriented development but bad service is enough to explain why)
That's sad but I can see that. Maybe more with train and metro stations though than light rail that often makes little difference to commute times vs a bus.
Readit News
> The vehicle is battery-powered, eliminating the need for overhead wires. It features an innovative turning system, enabling it to handle 15m radius curves. This allows for installation in tight corners within the existing highway. The Council intends for it to operate at a high frequency, providing a turn-up-and-go service. The vehicle has a capacity of 56, is comfortable and has low floors to enable passengers to embark and disembark easily. The vehicle has been developed to allow autonomous operation in future.
> The new track is laid just 30cm within the road’s surface, minimising the need to relocate pipes and cables, which is time-consuming and expensive. It achieves this by leveraging cutting-edge materials science, while still utilising standard rail parts to ensure ease of manufacture.
Battery powered trams have real potential, now that batteries with 5 to 7 minute charging and large numbers of charging cycles are a thing. That's compatible with typical end of line holding times. Steel wheel on steel rail is low friction, and you get most of the energy used to go uphill back when you go downhill. This could work out.
[1] https://youtu.be/XKN0MTCUSV0?t=265
If you were going up and down hills, would you still use steel wheel in steel rail unless you had some sort of cable to work with? I always thought the Muni did relatively level routes for that reason? The Lausanne m2 for example uses rubber (well, ideally you’d be able to just balance the train going up with the train going down, but that only works for simple inclines with limited stops). Actually, a battery powered rubber wheeled tram service on some sort of steep incline like SF’s cable car routes could get some wicked regen going down.
Even if level, they could still get some regen from making stops.
Revolutionary as the turning circle will be used at speed with passengers to traverse roundabouts in-lane. CVLR doesn't need turning loops, as the vehicles can be driven from either end.
LRT systems on which the existing minimum curve radius falls below 15 meters include:
• Boston—10 m (33 ft) and 13 m (43 ft) for the Green and Mattapan lines, respectively;
• Newark—10 m (33 ft);
• San Francisco—13 m (43 ft); and
• Toronto—11 m (36 ft).
https://onlinepubs.trb.org/Onlinepubs/tcrp/tcrp_rpt_02.pdf (1995)
At least in the US utility relocation also generally involves moving what was underneath to the side, so it can be accessed without disrupting the new transit line.
At last they were not trying to use agile!
It feels like that's putting this into a really awkward place in the tradeoff space. Trams work because they can scale higher than buses. That scale comes at the cost of more up-front infrastructure, much less flexibility, and needing dedicated lanes. So cities don't have trams everywhere, but they're only installed on routes that can support the scale.
For these you still have the up-front investment (just less of it) and inflexibility, but don't get the efficiencies of scale due to how small the capacity is.
Is this really just a bet that they can get autonomous tram-driving on city street approved a decade+ sooner than autonomous buses?
Buses however are slow (in London about the same as walking) and (outside London) prone to vanishing on timetable changes. Closing a rail link is tricky, you can be confident that if you live near a tram stop it will be there in 10 years. 60% of our local (say 10 mile radius) buses have been removed in the last decade, removing entire villages from service.
A rail solution allows you to read, a bus throws you around everywhere and makes you sick.
The ability for the tracks to be laid so shallow is in my view, the entire innovation and cost is the reason for this approach.
Even if all that falls through, I'm not gonna complain about it. We sorely need more public infrastructure in the UK. Even if an experiment like this fails, at least you actually get a tram line and experience out of it. Much better than a project which sucks up million then gets cancelled. (Cough cough HS2.)
Having to hold on to something discards it from my preferred list of solutions.
The tram they show in the animation also very much has a driver in the front.
If they can deliver on what they show in their demos, I don't see why the size of the trams or the infrastructure should be a problem. All the expensive stuff has been thought about, the system barely takes up any extra space, and the system is capable of scaling up by just sending more vehicles into service.
Deleted Comment
Lower flexibility is actually a feature when it comes to mass transit: People will build density along rail lines because they assume the town won't rip them up, making the rail line more valuable over time. A bus route can be cancelled the day after a disruptive mayor is voted into office.
I also don't see why you can't scale up the tram with additional cars, as long as you keep the lbs/sqft the same. 3 car trams are fine, 3 car busses are... not
It’s a worthwhile read BTW
I suspect these are too small to carry a significant number of passengers per hour
They’ll also probably never be autonomous as the challenge with autonomous is less the driving and more with passengers getting on and off, getting trapped etc
Deleted Comment
It's tiny, how it possibly carry all those 2x4s, powertools and sheets of plywood when I'm out doing manly things. I'd better go buy that monster truck so I can look like a real man.
Trams are one example of Light Rail, but so is the Docklands Light Railway in London (an exception to "on sight" - it's automatic), as opposed the the Tube (underground) which is Heavy. But the Welsh "metro" project's "tram-trains" (Stadler Citylink) are also Light, even though their tracks into the valleys are very much not urban in the usual sense - the full valleys journeys are over one hour with the current trains and go through mostly rural areas with small towns.
I haven’t found the projected figures for Coventry but it would be very, very awkward if they can’t beat the numbers above with a supposedly much cheaper track.
https://en.wikipedia.org/wiki/Trams_in_Besan%C3%A7on?wprov=s...
Still, there's no point comparing build costs between France and the UK as they're completely different cultures and jurisdictions. Instead, a more reasonable approach is to compare to recent similar project in the UK.
Edinburgh's tram covers 18.5 km and cost at least (they're still uncovering overruns years later) £1 BN. That's ~£50 MM or ~€60 MM per km. That's what CVLR should and will be benchmarked against.
VLRT seems gimmicky at first but the more I look at it the more sense it makes.
The Airport line extension cost £368m with 15 stops over 14.5km of track (which shakes out at roughly £25m/km), and was completed more than a year ahead of schedule and under budget.
Separated by huge distance of 20 miles, both have thousands of same EU laws )still on the books, share thousands of years of history and at one point ruled by the same aristocracy.
TLDR: Because they always try to do innovative things rather than just copy tried-and-tested methods from other countries.
They're using "Standard rail components, innovative construction" - standard gauge rail, but laid over a foundation of slab ultra-high performance concrete (UHPC), which allows for the shallower foundation / avoidance of utilities relocation.
Using UHPC to rethink infrastructure is the big story here, I think.
That's a _very_ small tram, smaller than most buses.
UK tram track construction typically involves deeper track beds compared to France/EU, using concrete slabs of 500-1000mm deep, is intended to protect utilities. In contrast, many European projects utilize shallower trackbeds, even with grassed areas, which are 300-400mm deep
They make all kinds of claims that don't stand up to over 100 years of history running trains. The claim they are innovative, but there is nothing new here, and no evidence they have looked at the real problems of transit systems. Someone is going to make a lot of money on this at the expense of the community that loses.
Trains have been around for a long time. You can buy all the parts you need for a good system off the shelf. You won't be saving money by designing something new, you just waste money on engineers to design something and then lose the scale factors you could get from buying the same thing as everyone else. If you buy the same thing as everyone else that means there will be a market for spare parts and thus in 20 years when (not if!) something breaks you can keep the system running.
Yes overhead wires are expensive - but they are a rounding error compared to track. Batteries are expensive too, and you have to buy a lot of them. Batteries need to be recharged which means these trams will be out of service often so they have to buy a lot more so that when one is out of service for charging the others can work. (you still need a few extra for maintenance, but battery charging is more common so you need a lot more)
If you want to build a train the best way to save money is to build exactly the same as everyone else does: standard off the shelf trains, running on standard off the shelf rails, and standard off the shelf overhead rail. If you want to innovate make sure that everyone is fluent in Spanish, Turkish, Korean, or Italian - because places where those languages are spoke build and run trains much cheaper than other places you can think of so you want to learn from them. (note that French or Japanese are not on the above list - while those areas do cheaper than English speakers, they are still expensive)
I'm not sure about the UK, but in the US most of the cost blowout for trains seems to be in stations, so focus all your innovation there: don't make them monuments to how much money you can spend. (The UK has cost problems almost as bad as the US, but I'm not aware of any study on where the issues come from, while at least in the US there are studies).
Anyway everyone is pretty sure that that something is wrong with the standard train economics as you describe them, because if there wasn't something wrong with it there'd be a lot more trains. I can't tell from the site, or from your comment, if this is the solution, or even worth doing as an experiment... but "don't change anything ever" doesn't strike me as productive either.
Innovation should require some knowlegde of what is already done - otherwise you invent square wheels.
I agree with much of your sentiment, and hope that the Coventry council is being challenged in these sorts of ways, but at the same time I recognise that each city is going to have quite different requirements for trams driving down the roads in its centre.
Perhaps a better push back is: why isn’t this just a better bus network?
There are different modes of operation that differentiate them but fundamentaly they are all trains and face the same issues
Eliminating overhead wires isn’t about cost. It’s about being able to build in existing urban areas that don’t want high voltage live wires everywhere, and likely already have above ground infrastructure they would interfere with.
You are speaking like a naive person that thinks that most the challenge is the physical world
But in UK most of the challenge is archaic and idiosyncratic laws, disproportionately powerful NIMBY’s and the treasury brain.
The treasury brain will approve a project with 1X capex and 10x opex instead of one that has 2X capex and 1X opex
The NYMBY is wild and unpredictable, they just killed project for a data centre placed on top of a literal dump because it would ruin the view of that dump from a motorway (nobody lives there)
A project to re-open 3 miles of railway that already exists took 5 years to approve and 80,000 pages of environmental accessment
But if it’s innovate and designed in UK it might just slip through
In Australia, highest cost is buying up required land and construction of buildings. We spent ~100mil USD on a single, open air platform for a line extension of exactly that one station. It was about 5 km of extra track. It is amazing we have any trains at all.
The answer is of course that rails provide major advantages on their own, primarily by allowing vehicles to travel much more efficiently thanks to the low friction of running steel wheels on steel tracks
“Thanks to the very low friction between the steel wheel and steel rail, railways can move a load using as little as 15% of the energy that road haulage needs.”
Gareth Dennis, How Railways will Fix the Future (https://www.penguinrandomhouse.com/books/761930/how-the-rail...)
There’s nothing stopping a road from being smooth but, logistically, there’s clearly no reason to rush to repair roads when they deteriorate. That means potholes get tolerated, potholes means suspension, and both of those mean bus-like rides instead of suburban light rail rides.
Railway track has to be flat. Anything less than perfect is intolerable so it tends to hold its maintainers to a higher bar.
I've found the new battery buses to be far more comfortable to ride in than older diesel buses since they remove the vibration when idling. The extra weight might mean more potholes to repair though.
And lastly badly maintained railway lines are just as prone to causing motion sickness as badly maintained roads.
The fact that buses are so flexible and easily (and cheaply) rerouted makes developers less likely to build developments that rely on access to transit, but once a community spends a hundreds of millions of dollars on a light rail line, they know it's there for the long term.
https://www.washingtonpost.com/dc-md-va/2025/05/27/steetcar-...
Jarrett Walker has a good piece about it: https://humantransit.org/2025/05/what-was-wrong-with-the-was...
I agree with him that in order to endure and justify a permanent operating subsidy a transit service needs to be useful and used by many people. Most American light rail doesn't meet that bar.
a longtail ebike, a pushchair with/for 2 kids (horizontal arrangement), a dining table for 6 people and 30 kg of cement
I tried it, and with most of em they don’t let you on a bus or you can’t fit but tram is fine
Modern urban light rail is also typically electric, using overhead power. Although buses can also use this.
This is one of the main reasons the super dense Japanese cities aren't as air poluted as other urban centers.
Bus rapid transit, when done right (basically, almost like a tram) can be quite successful: https://www.youtube.com/watch?v=fh1IaVmu3Y8
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