As anyone looking to properly understand London’s transport needs and network knows, context, background and best-practice are important. As readers might imagine, behind the scenes here at LR Towers we thus spend a lot of time sharing links and reading around the subjects we cover here.

We also occasionally share links containing good information about transport topics that we know we just don’t have time to cover. We also all, as authors, occasionally write elsewhere on this or tangentially related subjects.

This week’s reading list is below. If you’ve got something you feel we should read or include in a future list, don’t forget to email us at [email protected].

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There are 26 comments on this article
  1. The study and report on diesel particulates and pollution is the first time I’ve read in mainstream North American press about this issue. Of course it applies to all diesel hauled passenger trains, Via Rail, Amtrak, commuter trains… Fortunately in Toronto the GO Train system (GO stands for Government of Ontario) is already well underway on its electrification plans for 5 of its 7 commuter rail lines (the other 2 lines are owned by Canadian Pacific, but I can’t recall why exactly they are resistant to electrification, so shan’t speculate).

    I am hopeful that other media take up this up, to make it a health issue as it is in London UK. I write this aboard Via Rail (Canada’s nationalised passenger rail service), which places it’s Business Class car where I’m sitting (not on the mythical LR expense account I assure you), right behind the locomotive, so I really hope Via takes notice of this report and puts Business Class at the end of its trains. They can’t be poisoning their best customers can they? Plus it’s noisy behind the loco, with the many horn soundings for all the level crossings we pass.

  2. Greg Tingey says:

    WHERE did they get the map for CR2 in that “Rail Engineer ” article?

  3. Anonymously says:

    @GT….Lol, it’s the old Chelney Tube proposals!!! Presumably there’s some old document floating about somewhere where they have obtained that map?

  4. Mike says:

    LBM: it would also be likely to apply in some way to diesel-powered road vehicles. Given that the alternative to being inside a train would be being inside another, perhaps diesel-powered vehicle, it would be interesting to know the comparison with other modes. The comparison with city street pollution levels will be different, since vehicle (and hence emission) density will probably be higher on freeways and arterials rather than in the city proper, and I recall a study that showed that in-vehicle pollution was worse than on-street pollution – motorists tend to breathe in more muck than cyclists.

  5. @Mike

    Agreed, but I don’t know the levels. GO Transit had recently purchased new Tier 4 diesel locos that push-pull their fleet, which are supposedly less polluting and more environmentally friendly, but this study shows they still have a long way to go. I suspect that the stated ‘less polluting’ aspect is similar to that of London buses, in that only a few criteria were used, with particulate levels not being one of them. Pollution levels are an area where we do not have in-house expertise, so we welcome informed comment.

  6. Walthamstow Writer says:

    @ Greg – I read the article but didn’t spot the map. What a glaring error but nonetheless something of a shame that we’re not actually building that line.

    It’s interesting, to me anyway, that we seem to have a small flurry of “we must build CR2” messages emanating from City Hall with “TfL modelling” showing that multiple stations will cease to function if CR2 is not built. There’s also the rather dubious remark that “passengers using Euston will lose all their HS2 time gains in queues to reach the tube if Euston isn’t served by CR2”. That seems faintly ridiculous to me given CR2 is not exactly going be near the surface if it is built. Access time from Euston Main Line to the CR2 platforms will probably be in excess of 5 mins assuming no need to buy a ticket and then there’s wait time for a train.

    Looks to me like City Hall have decided that things are sufficiently precarious that a CR2 lobbying campaign is needed from now until whenever Mr Grayling decides if he’s going to release any more funding for the planning stage (apparently he’s due to decide this “Spring”).

  7. 100andthirty says:

    The map issue in the Rail Engineer has, I’m told, been fixed.

  8. Chris5156 says:

    I can’t find the link to it now, but I recall seeing a map of poisonous airborne particulates across London. You could make out every major road and most of the minor ones just by following the lines of heightened emissions, but the brightest and clearest line on the map was actually the GWML.

    I don’t wish to pit roads against railways in a “who’s the most polluting” competition; it just underlines for me the fact that diesel locomotives – of the aged HST type particularly – currently count heavily against the environmental credentials of the railways.

  9. Balthazar says:

    There was half a story about diesel pollution reported by the BBC early last year; I recall hearing about it on the Today programme but the only weblink now available appears to be this one:

    The notable “headline” was the level of pollution measured *inside* diesel trains.

    However, I say it was “half a story” because the lack of detail was rather infuriating. It was unclear whether the diesel trains between Bedford and St Pancras referred to were HSTs or 222s. This could be relevant (a) because emissions from the former are concentrated in power cars rather than spread along all vehicles and (b) because the air conditioning intakes are on the underframe on HST but at roof level on modern stock (personally I would not like to hazard a guess as to whether this means HSTs should be better than 222s in relation to internal air quality or not). There was a reference in the broadcast version to “the same type of diesel train” being used into Paddington, but of course Great Western HSTs have different engines than the Midland Main Line ones. And there was no follow-up on different routes/train types.

  10. Balthazar says:

    Re: Chris 5156 – your post crossed with mine, but note that all GW HST power cars have been re-engined with MTU engines, so the term “aged” cannot in fact refer to the equipment that produces the pollution in HSTs.

    It would indeed be interesting to see that map, and to see a new version in a few years’ time when almost all diesel operating into and out of Paddington has been eliminated.

  11. Balthazar says:

    I like the two mutually-contradictory crises facing TfL…

  12. ngh says:

    HST internal air quality:
    You can smell the brakes through the air-conditioning system when they get hot. Given the brake pads need replacing every few weeks a reasonable quantify of brake dust could end up inside as it does on LU stock in tunnels.

  13. @ngh

    I wondered what train brake pads are made of, so Mr Google offered this link (among many brake manufacturers’ links):

    “Natural fibres such as hemp can replace costly aramid fibres in brake pads, with no loss of performance and less impact on the environment, according to research by the Sustainable Technologies Initiative (STI). Brake pads are one of the key components in the race to develop greener transport, with 80m sets used in the UK alone every year. Since the use of asbestos was phased out in the 1980s, most have been formulated using aramid fibres. They also incorporate significant amounts of heavy metal compounds. Around 20,000 tonnes of dust containing these materials are discharged into the environment as the pads wear. New research into eco-friendly brake pads, backed by the STI, has shown how a switch to natural fibres, such as hemp, could offer a more sustainable solution. In the Ecopad project, researchers demonstrated how renewable fibres can reduce reliance on synthetic materials and allow heavy metal constituents to be replaced with safer alternatives. The outcome is expected to provide up-to-date solutions to the global transport industry and its friction material supply base. Our STI research promises the creation of an important future application and new market for natural fibre crops, said project leader Dr Luke Savage of the University of Exeter. Ecopad combines greener transport with greatly reduced costs for friction product manufacturers. With no loss of braking performance, the attractions are obvious and there has already been a great deal of interest from manufacturers and the public…”

  14. JimJordan says:

    Regarding the smell of brake pads on HSTs, a friend, many years ago, enjoyed relating that on the prototype Mk3 tests the output of the toilets was found to be sucked in by the A/C fans. This may be apocryphal but I think not.

    Re brake block materials, the use of regenerative, rheostatic or possibly hydraulic energy dissipation braking must be welcome. Did not the APT have some form of the latter?

  15. Balthazar says:

    I nearly referred to the link between underframe air intake and braking smell in my post of 13.31, but obviously I didn’t need to! I recall many years ago there was a Notes & Queries question in the Guardian about the same issue, which elicited two printed replies: one saying it was harmless and the other that it was carcinogenic. A bit like TfL’s crises as reported by Railnews, it would appear.

  16. Balthazar says:

    Re: JJ – dynamic braking is indeed a good thing, but only regenerative braking avoids dissipating the vehicle’s kinetic energy as heat, and so counts as an excellent idea (save 20-30% of all traction energy – of course you’d want to!).

    APT had hydrokinetic brakes. Unsuccessful in that application and notably not widely developed since. I think there is still a cut-away example in the National Railway Museum.

    Incidentally, that hiss on a Class 139 after it comes to a stand is the friction brakes applying. Yes, I said *after*.

  17. Balthazar says:

    Re: LBM – “Around 20,000 tonnes of dust containing these materials are discharged into the environment as the pads wear.”

    Aaaaarrrgghh! Over what time period? And in what geographical area? A meaningless statement without those details. The implication is annually in the UK, but it doesn’t actually say that.

  18. @Balthazar

    I know, the lack of detail is horrendous, but few appear to want to discuss the hidden secret that is pollution – out of sight, out of mind. Throw a few numbers around that are difficult to quantify…

    Whilst I know not which types of brakes Toronto’s streetcars use, the fact that the city kept it’s large streetcar network when almost every other North American city converted to diesel buses (occasionally via the electric trolley bus for a few decades) is a strong reason why Toronto’s downtown pollution levels are much less than other cities’ downtowns. I’ve seen the air pollution map for the city and it’s worst at highway interchanges.

    Airports likely produce different types of pollution (jet fuel vs diesel), making an overall pollution count necessary. As it stands, the politicians seem to be happy to have different pollution levels and labels confusing people, so they don’t have to spend money to address the problem.

  19. Graham H says:

    @Balthazar -indeed, the challenge thrown at the Networker designers was to save 1/3 on energy costs through regenerative braking. What got in the way, and what continues to do so, apparently is the ability of the substations to absorb sudden peaks in “reverse” supply (or so the engineers said) – the mirror image of the problem of a sudden peak in demand (notoriously a problem on the Guildford New Line, where the combination of station spacing and gradients meant that the timetable had to avoid too many trains starting at once.)

  20. ngh says:

    Re Graham H,
    Networkers – the GEC-Alst(h)om ones (465/2/9 and 466) have regen turned off because the on board electronics isn’t up to it. The 465/0/1 with the replacement Hitachi traction electronics do use regen

    Re LBM,

    Jet engines, diesel and gas turbines for heat and power generation* are all bad for NOx which is what that map shows. I remember one conversion with the EA that I didn’t win when installing 2 new CCGTs was their insistence on installing a stupidly high stack to dissipate NOx better as they could be certain the older generating equipment was going to get binned despite the new stack would have been on the site of the old one and the CCGT on the site of some former Oil and Gas fired steam turbines and the emission being far lower. In reality their computer said no as they couldn’t remove the impact of the existing emissions from the calculations…

    *Heathrow’s on site energy centre philosophy may be wasn’t such a bright idea!!! The latest addition is off site the other side of the M25 (and off the map!) to try to lower local emissions.

  21. Combined Cycle Gas Turbines (CCGT) are a highly efficient energy generation technology that combines a gas-fired turbine with a steam turbine.
    EA is the Environment Agency.

  22. Graham H says:

    @ngh – I seem to recall that when the 465/0s entered service,they were actually run in regen mode with the original kit, but that didn’t last long – perhaps only a few months. At the time, the move back to conventional operation was blamed on the substations, but you may well be right that the basic design was faulty (an “interesting” blame game, perhaps…)

  23. Balthazar says:

    Re: LBM – actually I was wondering whether someone was trying to manipulate data to make the problem look *worse* than it is in order to secure orders/investment/research funding…

  24. ngh says:

    Re Graham H,

    Regen with GTO power electronics and the processing power of microprocessor controlling the traction electronics was probably a bridge to far at the time.
    The quality of newer power supply rectifiers supplying the 3rd rail has improved and probably helps to as does the removal of TP huts had replacement with substations.

  25. Putters says:

    Re something being able to use the power from regen. When the Central Line trains were being brought in, one of the requirements was for the conversion of all the DC supplied lifts and escalators to either have controllers modified or be converted to LEB 415 supply due to the variations in speed generated.

    One of the stations where the machines were just modified (as they were due to be replaced / refurbished in the not too distant future) was Bond Street. The mod worked fine until one machine was removed from service whereupon the other two would regularly trip due to overspeed. I remember the resulting costs – closure or escalator loss at Bond Street for some reason at the time triggering some of the highest Lost Customer Hours penalties in the PPP contract – being hotly disputed at Attribution between Metronet and LUL as to whether it was a pre-existing liability of the Central Line Project or not.

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