Nuclear powered trains

[dcsprior]

Listen - why don't we just skip a generation and wait until they perfect propulsion powered by Dilithium crystals?

Because then we'll just use the transporters

 

[najaB]

It's not fail-safe if it's lying upside down leaking radioactive material after the locomotive has hit an HGV on a crossing though.

I'm not proposing nuclear-powered trains, just pointing out that it's not all doom and gloom and that we shouldn't reject an idea out of hand and before we've considered both the pros and cons.

Speaking of cons, containment is an issue. It does mean that any nuclear fission powered locomotive is best suited to low-speed haulage of heavy loads, rather than high-speed expresses.

 

[HMS Ark Royal]

The smallest nuclear reactors available at present are those that power nuclear submarines, they are too large to fit within any likely loading gauge.

Well if it was possible to make it a wee bit smaller, what about fitting a train with an Argonaut class reactor? I mean the Royal Navy had one in London for decades before they told anyone!

 

[fowler9]

I would suggest that the reason we don't have nuclear powered trains is because it it has been globally proven that it seems to make more sense to generate power at a fixed point and transmit that power than it does for each vehicle to carry its own power station. I am guessing it is the economies of scale. I could be massively wrong here and am open to suggestion.

 

[najaB]

I could be massively wrong here and am open to suggestion.

Nope, you are not wrong. I think (hope) this question was asked merely as a thought exercise.

 

[fowler9]

Nope, you are not wrong. I think (hope) this question was asked merely as a thought exercise.

I thought I was right but based on being an angry head at times in my past I thought it better to leave what I said open to question rather than say "Yes I am right". Being right isn't that important to me any more. Helps me in my job as a complaints manager. Ha ha.

 

[HSTEd]

The cost of one of these micro reactor locomotives would pay for the electrification of its entire diagram.

 

[6Gman]

Provided the type of reactor does not have a characteristic termed a positive void coeffecient (like the old RBMK type designs), and has appropriate safety systems in place, (together with safe operating procedures) I can't really see a problem with it.

Ah yes, I remember the Restaurant Brake Motor Corridor coaches.

 

[edwin_m]

Ah yes, I remember the Restaurant Brake Motor Corridor coaches.

You'd be wise not to go within 5 miles of the griddle car...

 

[AngusH]

I suppose it's marginally possible that something could be done with radioisotope thermoelectric generators. These essentially work by generating electricity from the heat of radioactive decay, rather than fission.

https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator

A smaller unit might fit into a locomotive I guess and might be safer than an actual fission reactor?


I suspect that it may be what the Russians are considering for their nuclear train, although I have no information as such to support this thought.

Definitely not to be used in the train, I read the article more carefully.

 

[themiller]

I think that the NII (Nuclear Installations Inspectorate) would require a safety case so onerous that no-one could afford to operate such a beast! The safety case alone would require (human) resources that even Sellafield could only dream of. Given that any such loco would be a steam engine with a nuclear kettle, would it have any advantages over an electrified railway? I would suggest that complying with the regulator's requirements would rule this out as a viable form of traction. In my opinion, it's an academic exercise only.

 

[47802]

Not withstanding Darandio's points about the mechanism of converting the heat output of the nuclear reactor into something which might actually power the train, how about the use of thorium pebble bed type reactors, which as these can't produce material for use in nuclear weapons, presumably this gets around HSTED's treaty restriction argument?

I think that the NII (Nuclear Installations Inspectorate) would require a safety case so onerous that no-one could afford to operate such a beast! The safety case alone would require (human) resources that even Sellafield could only dream of. Given that any such loco would be a steam engine with a nuclear kettle, would it have any advantages over an electrified railway? I would suggest that complying with the regulator's requirements would rule this out as a viable form of traction. In my opinion, it's an academic exercise only.

Indeed and the unlikely event you did come with a viable train how much would the Security cost to protect it from potential Terrorists, I'm sure they would queueing up to try and blow one of those up.

 

[cin88]

Listen - why don't we just skip a generation and wait until they perfect propulsion powered by Dilithium crystals?

They never go wrong

Apart from all the times that they do...

A train travelling at warp five would be a sight to see though

 

[JN114]

Apart from all the times that they do...

A train travelling at warp five would be a sight to see though

If it were travelling FTL, you wouldn't see it...

 

[theageofthetra]

I seem to remember on a previous post on this subject that the lack of cooling water made it a non starter even with the huge Russian loading gauge and the try anything attitudes during the height of the cold war. One area where nuclear seems to be a natural solution is on the largest container ships and tankers. I still find it amazing that in 2015 these huge ships are being powered by a recprocating diesel engine that has barely changed in principle since they were first fitted in ships a century ago.

 

[miami]

A party people mover uses 64kw, so let's say that it's in use for 30 minutes per hour, 16 hours a day, so 512KWh, or a requirement of 21kW

70 RTGs should generate that, weighing about 4 tonnes and using 20 cubic metres. So not really practical.
However it would be a nuclear papered train without the need for wires or steam.

 

[HSTEd]

A party people mover uses 64kw, so let's say that it's in use for 30 minutes per hour, 16 hours a day, so 512KWh, or a requirement of 21kW

70 RTGs should generate that, weighing about 4 tonnes and using 20 cubic metres. So not really practical.
However it would be a nuclear papered train without the need for wires or steam.

You would use a Sterling Radioisotope Generator, not an RTG. There are space rated units available and its a tad easier to repair a unit in a siding than half way to Jupiter or the heliopause .

Space rated units for such things are not really that good a comparison. A 20kW Stirling engine could easily be made to fit in a few hundred kilos. And a ~100kW thermal source would be a few hundred more kilos.

So far lighter than the space rated units would have you suggest.

Still a stupid idea but there we go.

 

[Big Mac]

The cost of one of these micro reactor locomotives would pay for the electrification of its entire diagram.

Now that' a good point given how expensive it can be to electrify some routes.
--- old post above --- --- new post below ---

Ah yes, I remember the Restaurant Brake Motor Corridor coaches.

Very good - that made me laugh!

RBMK, in Russian: Реактор Большой Мощности Канальный Reaktor Bolshoy Moshchnosti Kanalnyy, which can be translated as High Power Channel-type Reactor.

 

[Philip Phlopp]

Not a signalling engineer, certainly not a nuclear physicist, so forgive what could be a silly question, but as nuclear reactors produce a variety of Alpha, Beta and particularly the high energy Gamma radiation, what impact will these have on traditional copper based signalling systems.

We have a big enough problem not causing endless amounts of interference with OLE and well ordered 25kV, 50Hz supplies, won't Gamma radiation risk significant interference effects on our copper based signalling systems, on GSM-R and so on ?

Also, and I don't know much about this, but could they even upset fibre optic signalling, can the high energy radiation particles disrupt photons travelling down the fibre optic cables or the fibre optic detectors at the end of each cable ? I watched a program on BBC4 a few weeks ago where radiation from a nuclear reactor caused interference on a camera, so is that something that is a problem, can it be controlled within our loading gauge if it is, or is it another reason why nuclear powered trains are a folly ?

 

[Clip]

It's a damned stupid idea, the only flexibility you get is choosing which isotope kills people when it goes horribly wrong.

Its not all that stupid when you find out they have already done it in a bus

 

[najaB]

Its not all that stupid when you find out they have already done it in a bus

That movie was *amazingly* bad!

 

[Clip]

Steady on

 

[lyndhurst25]

I'm sure that the boffins at Derby RTC at least thought about the possibility of nuclear powered trains, when you consider that they were coming up with ideas like this-

https://en.m.wikipedia.org/wiki/British_Rail_flying_saucer

 

[LexyBoy]

So in summary:
Could it be done (technically) - Yes
Could it be done (politically, economically, safely) - No

Come to think of it, all our trains are nuclear powered at the moment... from fusion no less. It's just not generated at the point of use.

We have a big enough problem not causing endless amounts of interference with OLE and well ordered 25kV, 50Hz supplies, won't Gamma radiation risk significant interference effects on our copper based signalling systems, on GSM-R and so on ?

Also, and I don't know much about this, but could they even upset fibre optic signalling, can the high energy radiation particles disrupt photons travelling down the fibre optic cables or the fibre optic detectors at the end of each cable ? I watched a program on BBC4 a few weeks ago where radiation from a nuclear reactor caused interference on a camera, so is that something that is a problem, can it be controlled within our loading gauge if it is, or is it another reason why nuclear powered trains are a folly ?

Probably not - the interference caused on cameras is due to the gamma setting off the CCD - gamma radiation is in effect extremely high energy light and as such the detector registers it as such (a small proportion anyway, mostly it's too high energy and passes through).

If our train were emitting similar levels of radiation then it could cause disappointment among spotters filming, who would not only have poor quality footage but also be dead within minutes.

 

[najaB]

Come to think of it, all our trains are nuclear powered at the moment... from fusion no less. It's just not generated at the point of use.

Except the ones that are fission powered (see the point about LU up-thread).

 

[Domh245]

Except the ones that are fission powered (see the point about LU up-thread).

And where exactly did the Uranium used in those reactors originate?
(It was formed as a byproduct of something fusion powered, a long time ago)

 

[HSTEd]

And where exactly did the Uranium used in those reactors originate?
(It was formed as a byproduct of something fusion powered, a long time ago)

That is debatable, since it is certainly not formed as a byproduct of processes conventionally referred to when discussing fusion power.

 

[najaB]

And where exactly did the Uranium used in those reactors originate?
(It was formed as a byproduct of something fusion powered, a long time ago)

I suppose if you want to be totally pedantic (and I appreciate good pedanticism): where stuff comes from.

 

[LexyBoy]

And where exactly did the Uranium used in those reactors originate?

OK, I meant to put a "mostly" in front of "from fusion".

Not sure if you could call uranium a result of fusion power as IIRC the processes to form elements beyond iron are endothermic; as a byproduct it would count I suppose. Certainly it's formed by fusing things. And to be pedantic, uranium is not capitalised

 

[Oswyntail]

Presumably any nuclear train would have to be topped and tailed with Cl37s.