Could Chiltern Electrify with third rail?

[Dr Hoo]

I can hardly believe that we are having this discussion again.

The Electricity at Work Regulations (1989) obviously predate privatisation and the existence of the ORR. Essentially (so far as this thread is concerned) live conductors at lethal voltages have to be either (a) completely insulated, or (b) inaccessible/out of reach. Third rail clearly fails on both these points.

All activities relating to 'work' are obviously covered by the general duties under Health & Safety at Work legislation including 'as low as reasonably practicable' obligations.

Even back in BR's day there was 'concern' that third rail networks were non-compliant with the then-impending E at W legislation as it had the potential to make third rail illegal overnight. So such lines were taken out of scope. This does not, of course, make the electricity any less lethal!

As part of various changes to railway safety legislation over the years - following on from Clapham, Ladbroke Grove, etc. ORR has found itself as the custodian of railway safety, responsible for both approving new works and also for prosecuting breaches of H&S legislation.

Given that quite a few relatively minor rural lines with infrequent services have been electrified at 25kV - Harwich, Kings Lynn, Braintree, Southminster, St Albans Abbey, Largs and Alloa spring to mind - it is a bit of a stretch to claim that this far safer technology is somehow not 'reasonably practicable' at Rye, Uckfield or Aylesbury. In any sensible national electrification strategy routes through Oxford to Birmingham and Kidderminster are going to be done at 25kV anyway so Chiltern or its successors will need capable trains.

As I have posted before, my early railway career happened to cover working in North London, on Merseyside and in Kent. I was entirely used to third rails and thought little of them as a significant safety risk 'if you knew what you were doing'. Then, when I was working on the South Western I suddenly had two experiences in quick succession. A nine-year old schoolboy got onto the line through a hole in the fence deliberately made by rail staff to facilitate a short cut to a depot and was instantly killed. I had to attend the harrowing inquest. Then, not long afterwards, I was at an incident site where the conductor rail was displaced and some very experienced 'ETM' staff were re-connecting a damaged 'floater'. Through a sorry catalogue of poor adherence to proper rules and processes by several personnel the section was 'bridged up' and an employee working right next to me was electrocuted.

My appreciation of (and attitude towards) the third rail was never the same again.

As we have seen recently at Lewisham, Peckham Rye and Shepherds Bush, situations can get rapidly out of hand with large numbers of passengers suddenly detraining on open and energised sections of line. This is not the sort of risk to be extended!

 

[HSTEd]

I can hardly believe that we are having this discussion again.

The Electricity at Work Regulations (1989) obviously predate privatisation and the existence of the ORR. Essentially (so far as this thread is concerned) live conductors at lethal voltages have to be either (a) completely insulated, or (b) inaccessible/out of reach. Third rail clearly fails on both these points.

All activities relating to 'work' are obviously covered by the general duties under Health & Safety at Work legislation including 'as low as reasonably practicable' obligations.

Even back in BR's day there was 'concern' that third rail networks were non-compliant with the then-impending E at W legislation as it had the potential to make third rail illegal overnight. So such lines were taken out of scope. This does not, of course, make the electricity any less lethal!

But third rail installations continued into the privatised rail era!
5-6 years after this regulation was promulgated.

That is a bit much to claim it was only "transitional arrangements".

Also the regulations even state that there are times when a) or b) are impractical and that other methods can be used to ensure ALARP.

As part of various changes to railway safety legislation over the years - following on from Clapham, Ladbroke Grove, etc. ORR has found itself as the custodian of railway safety, responsible for both approving new works and also for prosecuting breaches of H&S legislation.

Given that quite a few relatively minor rural lines with infrequent services have been electrified at 25kV - Harwich, Kings Lynn, Braintree, Southminster, St Albans Abbey, Largs and Alloa spring to mind - it is a bit of a stretch to claim that this far safer technology is somehow not 'reasonably practicable' at Rye, Uckfield or Aylesbury. In any sensible national electrification strategy routes through Oxford to Birmingham and Kidderminster are going to be done at 25kV anyway so Chiltern or its successors will need capable trains.

And where will the magical money tree come to pay for all this?
25kV is far too expensive, every line worth electrifying at 25kV has already been electrified or is already committed to be so.

Diesel will continue indefinitely, and we just have to hope magical super batteries appear.

Honestly a reasonable compromise is probably to adopt an isolated 4th rail system.
That way there is no shock risk from contacting the rails, and a contactor on the train would allow trains equipped for the system to operate from conventional third rail as required.

 

[DarloRich]

@Dr Hoo - thanks for sharing your experience. I will be honest 3rd rail scares me. I have never felt comfortable, in my admittedly limited experience, of being on the track in such areas. I have never felt uneasy under OHLE.

However it is clear from the follow up post by @HSTEd that such real world safety experience is wasted here.

 

[HSTEd]

However it is clear from the follow up post by @HSTEd that such real world safety experience is wasted here.

Personal experiences can be extremely traumatic, especially in the cases of children or work colleagues on close proximity.

However we are in a situation where 25kV is far too expensive for electrification to progress.
If the goal is an electric railway, alternative technologies are required.

And right now there is precisely one alternate technology that is anywhere close to available, and that is third rail.
I would not chose third rail if I was developing it from scratch, but if we want electrification anywhere in the next decade then that is what we've got.

 

[Dr Hoo]

(Snip)

But third rail installations continued into the privatised rail era!
5-6 years after this regulation was promulgated.

That is a bit much to claim it was only "transitional arrangements".

(Snip)

I would struggle to recognise the period when the HSE had taken over HMRI but apparently failed to really understand railways as a golden era that we should return to.

This was the phase that saw Clapham, the King's Cross fire, Southall, Ladbroke Grove, Hatfield and Potters Bar.

 

[HSTEd]

I would struggle to recognise the period when the HSE had taken over HMRI but apparently failed to really understand railways as a golden era that we should return to.

This was the phase that saw Clapham, the King's Cross fire, Southall, Ladbroke Grove, Hatfield and Potters Bar.

Clapham and the King's Cross fire both predate HSE taking on HMRI don't they?

I thought that only occured in 1990.

 

[TheGrew]

Is OHEL with a lower voltage (eg the German 15Kv) any cheaper to deploy than 25Kv?

 

[HSTEd]

Is OHEL with a lower voltage (eg the German 15Kv) any cheaper to deploy than 25Kv?

It seems doubtful, unless the clearance standards for 15kV are any less conservative than 25kV.

 

[DarloRich]

Personal experiences can be extremely traumatic, especially in the cases of children or work colleagues on close proximity.

However we are in a situation where 25kV is far too expensive for electrification to progress.
If the goal is an electric railway, alternative technologies are required.

And right now there is precisely one alternate technology that is anywhere close to available, and that is third rail.
I would not chose third rail if I was developing it from scratch, but if we want electrification anywhere in the next decade then that is what we've got.

Goodness me. This is silly.

The cold hard facts are these: The ORR they say no.

I do not have the luxury of dealing with what we wish the world looked like. I have to deal with what the world is like. That will colour my responses to threads like this, especially in the face of views which are not based on that reality.

I am out.

 

[Bletchleyite]

Personal experiences can be extremely traumatic, especially in the cases of children or work colleagues on close proximity.

Very true. That's the reason I tend to take the line that victims are not the best people to be deeply involved in the decision of what to do in light of a serious incident - they will be disproportionately biased due to their emotional experience. You could have the same discussion with someone who had witnessed or been involved in a serious road accident where someone was killed, and if you asked them "should we electrify the railways using a cheaper method so we can spend more on road safety" they would I'm certain answer unequivocally "yes".

(I should note that I have not witnessed a serious road accident nor been involved in one, so my holding of this view is not based on that sort of experience).

 

[Bletchleyite]

Goodness me. This is silly.

The cold hard facts are these: The ORR they say no.

And yet how many things have been stated as impossible that have actually happened?

Proper gangways on new rolling stock?
Large overhead racks?
More table seats?
Seats aligned to windows?
Brand new LHCS?
Fitting engines under Tube trains (OK, OK, it hasn't gone well, but it has *happened*).

There must be more.

 

[Dstock7080]

The point you raise about the Met is very interesting though; I recall that there was a plan to upgrade the subsurface lines to 750V on the 3rd rail, and 0V on the 4th (return) rail. Did that ever materialise?

3rd rail adjacent to LU so effectively Marylebone - Neasden and Nesaden - Harrow-on-the-Hill, LU 750+0V 3/4th rail north of Harrow-on-the-Hill

SSL 750v plan was completed in October 2017.
Most of MET/District/Circle/H&C at 500+ 250- for 750v supply. Harrow - Finchley Road (remains at 630v but regen available at 790v)

 

[hwl]

Is OHEL with a lower voltage (eg the German 15Kv) any cheaper to deploy than 25Kv?

No the clearances are actually defined by the clearance needed if lightening strikes the conductor/catenary cables /other live parts and the clearances are hence an order of magnitude bigger than that for rail voltages.

Fitting surge arrestors close to low bridges/tunnel entrances is a new /experimental way to reduce required clearances.

 

[ag51ruk]

Third rail at 750V has continued to be added on extensions to the DLR - is that allowed because it is a different system (bottom contact), the rail is protected or that the system doesn't have foot/road crossings so is considered segregated enough that there is minimal risk? There must still be a risk for staff on the track, or to trespassers

 

[Bletchleyite]

I believe bottom contact is considered differently, yes, as you are very unlikely to accidentally come into contact with the conductor e.g. when stepping over.

 

[option]

There are places other than London!

Oxford will be OHLE, & that will likely be extended to Banbury, so those GWR services are completely electric.
The Snow Hill lines will be OHLE, so thats Leamington-Stourbridge (possibly further). The gap between Leamington & Banbury will be filled.
East-West Rail will be OHLE (& I see the Bicester-Bletchley-Aylesbury section being built first)

The High Wycombe route is then infill, which gets OHLE to Marylebone.

Why would any operator, or ROSCO, then want the complication of stock with 3 systems?

 

[NickBucks]

The solution must surely be hybrid rolling stock utilising the third rail system in situ with battery or hydrogen power for the non-electrified sections

 

[HSTEd]

There are places other than London!

Oxford will be OHLE, & that will likely be extended to Banbury, so those GWR services are completely electric.
The Snow Hill lines will be OHLE, so thats Leamington-Stourbridge (possibly further). The gap between Leamington & Banbury will be filled.
East-West Rail will be OHLE (& I see the Bicester-Bletchley-Aylesbury section being built first)

The High Wycombe route is then infill, which gets OHLE to Marylebone.

Why would any operator, or ROSCO, then want the complication of stock with 3 systems?

And who is paying for these unfunded 25kV projects?

None of these things are likely to happen, except perhaps E-W rail electrification, and last I heard even that had been deferred.

 

[option]

Hi
As The CMLs bridge are too low for 25Kv AC OHLE, would the DfT allow Network Rail to electrify with Third Rail, even though its outdated, but it's better than a carbon-dioxide Mainline. Also the HOH-AMR section is Tube third rail, so it makes sense, surely?

Anyway I just wanted your thoughts

Thanks

I don't see any way that that is of any help, as the LU power infrastructure is not going to be able to support the massive additional loads of mainline trains, & there's no way that LU/TfL would fund the upgrades required.

 

[59CosG95]

And who is paying for these unfunded 25kV projects?

None of these things are likely to happen, except perhaps E-W rail electrification, and last I heard even that had been deferred.

I think @option was referring to if/when electrification was announced, that the projects in question would be 25kV AC, rather than 750V DC.
Besides, OLE to Oxford is (as I understand it) still likely to happen now that the area's been remodelled & resignalled, although everything else seems to be hypothetical extensions thus far.

 

[dm1]

I don't see any way that that is of any help, as the LU power infrastructure is not going to be able to support the massive additional loads of mainline trains, & there's no way that LU/TfL would fund the upgrades required.

It's almost definitely cheaper to upgrade a few substations to supply more power than installing catenary and masts on an already electrified line.

In any case the power has to come from somewhere (whether 25kV or 750V) and thus those substations (albeit slightly different ones) will be needed in any case.

In short: if upgrades are required, I'm sure Network Rail would pay for those rather than for installing new infrastructure themselves. It's not like National Rail sharing power supplies with LU is anything new ( see LO on the DC lines)

 

[apk55]

The power supply on most of LU is quite limited to about 2MW per train which probably means that the trains would not be any quicker than the existing diesels.
I think on the power supply on this section to Chesham they have probably stretched sub station spacing to the maximum so that the only way that the power supply could be upgraded is by doubling the number of substations.
Dual electrification should not be a problem on the section as the DC return current path is isolated from the running rails by the fourth rail, it is the DC return voltage drop along the running rails that causes problems on AC electrification.
The other line out of Marylebone is an obvious candidate for AC electrification as it may link up with other possible AC lines at Oxford and Banbury.
Therefore I would stick to 25KV AC

 

[Chiltern006]

The power supply on most of LU is quite limited to about 2MW per train which probably means that the trains would not be any quicker than the existing diesels.
I think on the power supply on this section to Chesham they have probably stretched sub station spacing to the maximum so that the only way that the power supply could be upgraded is by doubling the number of substations.
Dual electrification should not be a problem on the section as the DC return current path is isolated from the running rails by the fourth rail, it is the DC return voltage drop along the running rails that causes problems on AC electrification.
The other line out of Marylebone is an obvious candidate for AC electrification as it may link up with other possible AC lines at Oxford and Banbury.
Therefore I would stick to 25KV AC

Yes, but you have to put into the mix that most, if ALL of the bridges over the CML are low, and wouldn't fit 25KV wires, but the 750V DC doesn't need to have bridges pre-built, and if you add it us, it's a lot less hassle, yes there's more closures but that's just on the railway, the CML crosses some major roads and closing them as well as the railway would be a massive hassle

 

[59CosG95]

Yes, but you have to put into the mix that most, if ALL of the bridges over the CML are low, and wouldn't fit 25KV wires, but the 750V DC doesn't need to have bridges pre-built, and if you add it us, it's a lot less hassle, yes there's more closures but that's just on the railway, the CML crosses some major roads and closing them as well as the railway would be a massive hassle

Well, if it's a massive hassle, it is what it is and there's not much to be done about that if there isn't any other solution. A lot of bridges over the GWML were low, and most of them were replaced; Steventon & Cardiff Intersection bridges being the notable exceptions.
Surge arrestors could work, but at the end of the day, the decision to replace a bridge or fit surge arrestors comes down to cost, irrespective of inconvience to the public who wish to use that road and no other road.

 

[jfowkes]

If there wasn't 3rd rail power on a relatively small bit of the CML already, I expect this discussion wouldn't even be being had. 25kV OLE would be the obvious choice for a heavy rail line from London to Birmingham. Personally I don't think the 3rd rail section changes that conclusion very much.

 

[59CosG95]

Also, if "the CML crosses some major roads", it seems from that wording that the CML is above the railway, which is far less of a concern to road users than if "the major roads cross the CML", which would imply that the CML is below. In that case, it would only be a hassle if the bridge is low; if the road was quite important to traffic, a temporary solution would no doubt be sought. (The Hammersmith Bridge may well be getting a temporary twin beside it while urgent repairs are carried out).
Worth also pointing out the slightly generous GWR loading gauge found on the CML (a legacy from pre-grouping days)...

 

[hwl]

If there wasn't 3rd rail power on a relatively small bit of the CML already, I expect this discussion wouldn't even be being had. 25kV OLE would be the obvious choice for a heavy rail line from London to Birmingham. Personally I don't think the 3rd rail section changes that conclusion very much.

Exactly, the debate is only around part of the London end

 

[E16 Cyclist]

Just to go off at a slight tangent, but I’m surprised nobody at extinction rebellion has thought to target Marylebone as it is now the most polluting station in London. But saying that it isn’t a sexy target and they are more interest in being seen that anything more tangible

 

[option]

And who is paying for these unfunded 25kV projects?

None of these things are likely to happen, except perhaps E-W rail electrification, and last I heard even that had been deferred.

I think @option was referring to if/when electrification was announced, that the projects in question would be 25kV AC, rather than 750V DC.
Besides, OLE to Oxford is (as I understand it) still likely to happen now that the area's been remodelled & resignalled, although everything else seems to be hypothetical extensions thus far.

Indeed.

Oxford will happen, & it will be 25kV AC OHLE. So, that's one Chiltern end point wired.

Snow Hill electrification will happen. That's another end point.
[ There is increasing pressure to get diesel, & other fuels, out of urban areas. Majority of the services are commuter/local, which EMUs are perfect for.
Snow Hill, Moor St, Jewellery Quarter & Bordesley are all in the new Birmingham Clean Air Zone. Rail isn't impacted by that, yet. Snow Hill - Stourbridge is very urban. So is Snow Hill - Solihull.
Stock on the WMR services is 10 years old, Chiltern is 20 years old. XC is 20 years old. It will need replacing at some point. ]

East-West Rail, if/when it gets built, will be electrified with OHLE. Oxford, Bletchley & Bedford are already done that way.
So, that's either services they will run, or services & infrastructure that directly connect with the existing Chiltern lines.


The Chiltern lines go over OHLE at South Hampstead & West Hampstead, with the High Wycombe route going over OHLE at Wembley as well, & the Aylesbury route going over OHLE at Kenton.
That would suggest that suitable power supply infrastructure for 25kV isn't very far away.

 

[Bald Rick]

Given that there was a decade of major third rail projects between the promulgation of these regulations and the cessation of major third rail electrification work in the late 90s. I have to ask why it was ALARP then and isn't now?

There’s lots of things that were considered ALARP in the 90s that aren’t now. For example, not providing a system that prevents or mitigates trains going through red signals. Or providing Auto Half Barrier Crossings on new bypasses. Or having doors that could be opened whilst a train was in motion.

As I said earlier, the ORR has not put a blanket ban on new 3rd rail installations, but you do have to do a lot of work to demonstrate why it is, overall, better than an alternative system. Such an argument is much more likely to succeed for short extensions with mitigation (like the East London Line), than a long installation, particularly in an area without the ocnductor rail.