When MGR trains were climbing Worsborough bank with 2 x Class 76 on the front and 2 on the rear, no other trains were permitted in the Strafford substation section.
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Cost of electrification OHLE vs 3rd rail
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So what was the point of all the regenerative capability installed then?
I know, from personal involvement, that the Crossrail team did follow a similar testing regime, that’s why it’s not in public service, it’s not proved to be safe yet. Surely that’s what you and everyone else wants?
Well we wish you well, but my personal involvement is a gross inconvenience by Crossrail, years to develop, and funded in all that time by myself and others with the Mayor's Precept on our council tax bills, suddenly not starting on time, not getting me across London, and with no clear idea of when they plan to be ready. And if even the power supply is still not proved to be safe yet (come on, electricity supply is not rocket science, it's a well-understood set of principles worldwide) then one wonders …
Which brings me back to that weekend in the 1980s I saw them put the third rail down so easily from Stratford to North Woolwich.
Mikey C
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Neither the Marshlink nor Uckfield lines are high speed, they are classic "low intensity" 3rd rail routes really, where a cheap 3rd rail electrification scheme would be perfectly adequate
The problem on Worsborough bank was the maximum current that the Mercury-arc rectifiers and feeder cables could handle.
In the Netherlands double heading of electric locos on freight trains was not permitted for the same reason.
Heavy freight railways using DC current eg. Milwaukee Road or South Africa usually used 3000 Volts
supply.
The book "Woodhead The Electic Railway" by Foxline has a lot of interesting photos of Substations and power supply.
No longer involved, retired October 2017, but I do keep in touch with my erstwhile colleagues.
Railwaysceptic
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Plus, of course, the Marshlink Line runs into Ashford Station so no new spur would need to be constructed. HS1 has no spur to Marshlink.
I do not usually post on forums and I maybe slightly biased but 3rd rail does present a reliable option for electrification and many of the comments posted on here are based on myths and not real facts. Conductor rail systems offer a cheaper, better looking and more reliable option to overhead systems. There are some disadvantages but there are also many advantages but the major one is cost, conductor systems are at least 50% cheaper than the OLE equivalent. If they are that outdated, then why do over 50% of modern metro system use them?
Proposals have been looked at to link HS1 with Marshlink, either with a connection at Tutt Hill or with additional crossovers at the west end of Ashford Internaitonal. Both have quite an unacceptable amount of line blocking.
Dr Hoo
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Could you provide some (unbiased) case studies to support these claims, please?
3rd rail is not simply 'outdated', it is just inappropriate for some applications. Metro railways run slower trains, shorter distances between stops and mostly where physical public access to the track is restricted or as good as impossible. For example, most of the LU tracks are well fenced off or in tunnels making casual access in the way that even the UK's mainline railway does much more unlikely. Similarly, most modern metro systems around the world that use exposed medium voltage conductors near ground level protect the public (and their staff) from accidental (and deliberate) access to them. The London Underground has had 3rd and 4th rail power for over 100 years but is permitted to continue its use under grandfather rights. New underground stations are provided with platform edge doors as a safeguard.
The issue in this thread is the existence of a considerable network of 3rd rail tracks on what was the old Southern Railway. Much of that track passes through suburban and rural districts and many level crossings where access is difficult to control so it doen't have anywhere near the same protection as even the LU metro system. Consequently, the ORR has dictated that no extension to the network will be allowed using 3rd rail electrification, in the interests of safety.
Depending on the type and lenth of land traversed, 3rd rail is not necessarily 50% of the cost of OLE, and if the entirety of the electrical installation is included, i.e the power feeds and substations, there are many cases where OLE is positively cheaper, - especially where a high performance line* is required, demanding much more available power.
* high performance as in high speeds (over 100mph) and high power motive power (over 8000hp for all trains in the section).
As for "better looking and more reliable", - the former is an opinion and many here might disagree and the latter may be true comparing metro systems with early OLE systems, (e.g. fixed tension systems and headspans at high speeds) but comparing like for like, including all likely climate conditions, that may not be true.
Mikey C
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But what's the point of not allowing 3rd rail installation on slow, stopping services like Marshlink or Uckfield, when there are NO plans to replace the 3rd rail elsewhere on similar routes? If there actually was a plan to remove all the 3rd rail in the next say 30 years, then yes I would understand it, but that's not the case and what are the chances of even the 3rd rail on the 100mph SWML going now?
Dr Hoo
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If you were responsible for ‘proposing’ or ‘approving’ a completely new third rail installation on a route with many level crossings and unstaffed stations where none had existed before it is a big ask to demonstrate that the wholly new risk is ‘as low as reasonably practicable’. Have you ever had to face a case of a nine-year old being electrocuted on a third rail after trespass? Some of us have.
Well both Marshlink and Uckfield lines traverse large tracts of open countryside, skirting outlier estates in villages and with level crossings. So there is considerable scope for intrusions into hazardous reas of the railway. Whether the line is fast or slow, 750VDC gives that same fatal electric shock.
As far as other lines are concerned, they have grandfather rights that one day may be withdrawn when the need to replace the 3rd rail installation occurs, - especially when there is significant end of life civil infrastructure to deal with. As for main lines such as the SWML, being on a trunk route, there may be pressure for the line to be upgraded to handle heavy and fast freight trains no longer hauled by polluting diesel locos. The inability of the 3rd rail on the SWML will be seen as an excuse for the FOCs to stick with diesel, which of course to them means throughout the journey, e.g. to the Midlands, North or further.
Wychwood93
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To continue the slightly off-thread theme - the FOCs from down here have little option - tri-mode locomotives, possible (yes... but). The 'electric spine' was a good idea but, and there is always another one of those, is that to cater for the FOCs the diversionary routes for intermodals etc. would have had to have the 'dangly wires' installed. In other words, Southampton to Basingstoke via Laverstock to start with...…… an additional 60 or so miles of not too cheap stuff. Reading to Basingstoke is on the cards - how far down the pack and who shuffles it? If the AC overhead was installed where I have just mentioned, it would then leave intermodals etc. that go up the SWML to the east of Basingstoke, then hanging a left at Byfleet towards Virginia Water and continuing to, say, Ripple Lane - you could do that and the continuation with a bi-mode. Whichever way it is played, it is expensive. From 'down here' the FOCs have, at present, no other option than the diesels - the 'adblue' yields, I believe, nitrogen and water from the urea additive?
Mikey C
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When we can't even finish the planned electrification projects elsewhere in the country, there is no chance of a politician outlawing the existing 3rd rail lines in any foreseeable timescale.
"Sorry we can't electrify your diesel line as all the money and resources are being sent to Kent and Sussex so that we can replace their 3rd rail"
Yes replacing the 3rd rail infrastructure with like will cost money, but it will be massively less than the works required to rebuild tunnels and bridges across the Southeast.
HSTEd
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But they won't need to replace the entire third rail installation at once in real life, upgrades will continue like as traffic grows. The best case for third rail removal was the Island Line, and they couldn't even make a case for that!
And that is without any attempt to mitigate the risks of third rail using modern materials and technology.
For years we've been told that third rail had reached it's potential and no further improvements could be expected..... and then improvements in performance are delivered anyway.
There is a reason the Electric Spine and the BML conversion is no longer proposed in any Network Rail documentation.
"Fast freight" died in the 50s, if not before.
The vast majority of freight locomotives in the UK have power ranges that are easily achievable with third rail.
A class 66 has an at-rail power of about 2200kW, which is comparable with a single 5-car Class 444 unit.
The power demand of freight would be negligible.
There is no inability that cannot be solved with a power upgrade programme which is almost certainly cheaper by an order of magnitude (or more!) than the billions it would take for a 25kV conversion.
FOCs aren't interested in electric operations because no matter how expensive diesel gets, they know the Government will pour more subsidy money down the drain to keep them running for political reasons.
This is why the only modern electric freight locomotives in the UK (which are Class 92s) were laid up, exported or used on outdated passenger operations.
A Class 88 is a bad joke of a freight locomotive.
Neatly missing the point about "especially when there is significant end of life civil infrastructure to deal with". Tunnels, bridges and other rail related infrastructure does actually wear out, and/or become unsuitable for its intended use in modern times. Most of the mainline bridges and tunnels (e.g. the SWML), were built over 100 years ago. Indeed, the Basingstoke to Winchester section was opened in 1840, some 197 years ago, so there is very likely some serious work needing to be done at some point. Not necessarily this year or even in the next 10 years, but at some time, there will need to be serious renovation or even replacement done. That is why most bridge rebuilding in the last 20-30 years has been built to provide greater clearances, in many cases, meeting the requirements of OLE, so electrifying or converting an existing line will not necessarily require every structure to be replaced.
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Do not underestimate the increasing pressure to remove IC engines wherever possible, (i.e. not wherever 'convenient'). Once most CO2 producing road traffic is on it's way out, attention will turn to other sources, including rail.
The 3rd rail system is not more reliable than AC OLE system. Far from it. There have been several disruptive failures of the 3rd rail system in the last few days, one of which was just outside one of the major termini (and caused no end of grief). But they don’t get mentioned on here as they are less obvious, and pictures of a burnt out feeder cable are less ‘exciting’ than an LNER train with the wires wrapped round it.
HSTEd
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Once carbon dioxide emitting road freight is gone many of the arguments in favour of rail freight become much weaker.
Baring massive political pressure to keep toy railfreight operations going it is likely that it's market share will be allowed to shrink.
Not sure I buy that. Carbon emissions are (usually) a negligible factor in the decision process for logistics companies (notwithstanding the logos on Stobart / Tesco vehicles). It’s all about cost.
Now of course it could be that low carbon road freight becomes cheaper than current arrangements, in which case there will be some loss to the roads. But it won’t be because of carbon emissions themselves.
HSTEd
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Yes, and one of the primary reasons the political calculation is made to prop up rail freight through direct payments and artificially low access charges is to mitigate environmental damage like carbon emissions.
Once there are no more road carbon emissions that political calculus changes, almost certainly not in rail's advantage.
There’s not much in the way of direct payments though. And the low access charges are as per the law on marginal costing for open access (which is what freight is).
What Government is switched on to is using relatively low spend on rail freight to avoid much higher spend on capital projects on the roads.
HSTEd
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And freight receives vast amounts of capital expenditure to allow it to pay "marginal costings".
Werrington Dive-under, as an example, only has to exist because of freight and costs £200m to increase the capacity of the network by a handful of freight trains.
Except as the road network is not actually at capacity due to temporal shifting, it is not clear at all that increasing road freight movements by a handful of percent would actually do that much to increase congestion.
In other words, extra lorries would tend to avoid congestion by travelling at night instead.
It’s not about congestion, but damage to the roads.
Railwaysceptic
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Quite possibly, but that will make electrifying from Ashford to Hastings with OLE even more expensive. The only sensible propositions are 3rd rail DC enabling Brighton to Ashford trains or stick with diesel.
JohnElliott
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I wonder if the ORR would approve a third-rail electrification if combined with a conversion to overhead elsewhere, so that the overall mileage of 3-rail remained constant or diminished? For example, converting Southampton-Weymouth to AC and using the recovered DC equipment for the Marshlink or North Downs routes.
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