Back in July, the council was pushed by Auckland Transport to make an urgent decision to approve additional funding to buy much needed new trains. Primarily this was to provide additional capacity on the network by enabling all trains (except Onehunga ones) to be able to run as six-car sets. However, at the same time AT wanted to address the issue of the Pukekohe diesel shuttle. With full electrification not expected till at least 2025 they looked at the option of battery powered trains. A few more of which would be needed to also serve Pukekohe.

Below are the options the presented to the council with Option A assuming diesel shuttles would continue to provide service to Pukekohe.

To address the problems and opportunities, AT shortlisted two main options utilising the Better Business Case methodology, one of which has two variants. The options are:

  • Option A: purchase 15 three-car EMUs at $133 million
  • Option B: purchase 17 three-car IPEMUs
    • with CAF (supplier of the current EMUs) batteries at $207 million, or
    • with Korean (LG) batteries at $174 million.

Option B, the CAF supplied battery option, was recommended and approved by the council but with a caveat that the NZTA commit to funding at least 50% (and AT find an additional $50m from their capital budget).

Just a month or so later and with the election in full swing, both major and most minor parties said they supported electrification sooner. This was not an unexpected position given the noises that they had been making earlier. The NZTA have leaped on that and stopped the battery option. Here’s what an update to the Council’s Finance Committee (10mb) says:

Change to the purchase of additional trains for Metro Rail

  1. In July, this committee approved in principle the procurement of 17 three-car Independently Powered Electric Multiple Units (IPEMUs) at $207 million to meet forecast patronage growth from 2019, subject to equal share of the cost by the NZ Transport Agency (NZTA). The resolutions are in Attachment A.
  2. A key consideration for the IPEMUs over the standard Electric Multiple Units (EMUs) as the base case option was the ability to operate IPEMUs in the un-electrified network between Pukekohe and Papakura, based on the assumed date of electrification to Pukekohe of 2027/2028.
  3. Subsequent to the council’s decision and just prior to the intended confirmation to proceed by the NZTA board, the government announced its intended funding of electrification from Papakura to Pukekohe. The NZTA board therefore considered that it could not approve the 17 IPEMUs purchase if early electrification would provide a similar service level with the lower cost EMUs.
  4. Consequently, it only approved the base case of 15 EMUs (Attachment B), for the network requirements with recognition the matter may be readdressed when there was more clarity on electrification timing and its impact on the business case. This is anticipated to occur before 15 December 2017
  5. The EMU option required less capital at $133 million. NZTA agreed to fund 51 per cent of the total cost, a share of $67.8 million, and the remaining $ 65.2 million is required from Auckland Council.
  6. AT is seeking the approval from this committee to progress with the base case option of purchasing 15 EMUs in the interim to ensure an order can be placed with CAF (supplier of the current EMUs) in order to ensure the delivery of the rolling stock in 2019. CAF has agreed to a variation by 15 December with no impact on delivery time.

Here’s the NZTA letter to AT informing them of the decision. Of note they say they’ll reconsider the battery option “if this is warranted following further investigation of the Pukekhoke electrification and subsequent Government decisions”.

Below are couple of thoughts on all of this.

  • It felt at the time that AT were rushing this decision when it had already seemed likely electrification would become an election issue.
  • It’s not clear what the timeframes are for the “further investigation” mentioned by the NZTA. There’s a risk that all of the noises during the election were just normal political noise and that the wires still won’t be strung up any faster. By the time that could become apparent it might be too late to change the order to battery trains thus delaying much needed improvements in service.
  • The NZTA decision was made in August, before the election, I can’t help but wonder if they were looking for any reason not to go with the battery option – or more likely to not have to spend as much.
  • Ultimately I think that not going for the battery trains will end up better. Normal EMUs can be delivered and made operational faster and some of the extra touted ‘features’, such as being able to run on the western line during CRL works, were overblown by AT.
  • We’re ultimately going to need a lot more trains in the future once the CRL opens. Perhaps the money saved on buying normal trains will make that easier in the future too.
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    1. I think the batteries were expected to be buggered by the time Pukekohe was electrified, which would mean new batteries would have to be purchased anyway. Probably makes more sense to get battery units in another tranche if they are serious about Pokeno in the future.

    1. Or attach a diesel locomotive. Like used to be done Paekakariki – Paraparaumu before the wires went up in the 1980’s.

  1. Matt, just a question on the use of BEMUs on Western line during CRL works. You say AT’s case on that was overblown. How so?

    1. Because they’ll be in use serving Pukekohe. Can’t have them doing both at the same time. It was only put in the business case to make it sound better to councillors.

        1. There will no doubt be many, many points during the CRL works where they will need to depower sections of overhead lines to work in and around the tracks.

  2. One one is ever going to want to go that far out of town. OOPS! Sorry, that was the excuse for reducing Grafton bridge to 2 lanes.

  3. Thanks for the update Matt, these are sorely needed so, considering these won’t hit the rails till 2019, it’s encouraging to see some recognition of urgency on their behalf, however was there any indication why they have dropped to 15 EMUs from the initial 17 IPEMU’s?

    1. Because you only need to 15 to achieve the stated goals if you use regular EMUs.

      Basically you need 15 new EMUs and wires to Pukekohe to run six train sets everywhere all of the time. You need 17 BEMUs to run six car sets to Pukekohe all the time and then you can use the existing EMUs to run six car sets on everything else. Part of the difference is that you need fewer spares for one fleet of 73 trains than for two sets of 58 trains and 17 trains respectively.

      1. Thanks, a pretty straightforward reason. It’s probably not at that stage of the process yet, but it will be interesting to see if these will offer an improved internal layout over the existing carriages – extended overhead handrails, different seat layouts etc.

        1. Going on the train with my bike today I was reminded how slow the doors open on the middle carriage. I certainly hope that the new tranche of EMUs has a faster retractable bike/wheelchair/pram support plate meaning the middle carriage doors on those EMUs at least will be faster for opening.

      2. I would have thought the difference was just because EMUs wont be running to Pukekohe initially and the diesel shuttles will continue. This would mean less route kms, thus less trains needed.

        1. I can’t see anywhere in the business case that specifically refers to what you described, although it is an 84-page document so I may have missed it.

          My read is that there are no wires to Pukekohe for Option A, happy to be pointed to the page that shows otherwise though.

        2. Sorry, you are quite right. Section 2.6.3 of the business case states that 15 EMUs are needed for full six car services. Seems crazy to not buy enough to run six cars all the way to Pukekohe at the same time.

        3. I guess the business case was based on electrification in 2027/28, so they would be bought as part of the post CRL fleet expansion.

          I’m guessing if electrification is bought forward then they may need to adjust the order to 17 regular EMUs. Looks like we will know by December 15 either way.

    1. Good point, why order more 3 car emus? when the need is for 6 or 7 car emus? Maybe that would be a cheaper option since there is fewer driving cabs.

      1. I fully support permanent 6 car EMUs, as long as we can always have enough 3 car EMU ‘s to operate high frequency off peak services.

        1. The current fleet of 57 units is more than enough for 10 min frequency on every line with 3-cars units. On weekdays it is likely they would be 6-car units off-peak anyway as I think it is more expensive to have staff on to stable the unneeded cars than it is to just leave them running as 6-car sets.

    2. Well they say all the stabling and maintenance is only set up for 3-car units. But makes you wonder if they couldn’t sort that out and order 15 inserts to extend three car trains to six cars.

  4. Is there any hope of getting the design of the CRL platforms extended to take 9 car trains? Or is it too late now?

    Interestingly I read that one of the benefits of the removal of Newton Station, was that Aotea and Karangahape stations could now have flat platforms, whereas previously they had been designed on a slight incline. This suggests that it would be possible for the platforms to be extended from their current design.

    1. It is not too late to extend the platform. I think the project is in detailed design. But I am not sure if there would need to be changes to consent or if there are engineering constriants. There might be building foundation/geotechnical or land owner issues that might need to be addressed. There could be significant cost or time table Issues

    2. Newton station was always a funny one. Too close to both Newmarket and Grafton.

      Wasn’t it only built to service demand during the Newmarket rebuild?

      1. I think you are confused with the temporary Newmarket West platforms. Newton was planned to go deep under the top end of Symonds Street, at the intersection with new north road.

  5. Is it possible to define your acronyms the first time they are used? Stopping reading to google acronyms disturbs the continuity of reading. Apologies for nitpicking.

  6. I thought the battery trains idea was a bit knee-jerk really unless they were able to be easily converted. BUT maybe they could have gone on to do a Hamilton service, no idea what their range is though.

  7. How about bridging the gap for electrification to Helensville? AC to Swanson, batteries to somewhere past Waitakere Village then AC again to Helensville.

    1. I assume you suggest this to get around the Waitakere tunnel problem where its impossible to get OLE through?
      Problem may be worse than that since new safety rules preclude passenger cars that do not have front/rear exits as apposed to side only carriage exits such as the AM emus.
      This tunnel may need reworked, rebored, or the line rerouted. All probably expensive options.

      1. Much cheaper to purchase new units with end-doors and run only these units on the Helensviile service.
        Since more new units would be needed anyway.

        1. In Wellington they enlarged the tunnels (Johnsonville Branch) rather than specifying that the Matangi EMUs have end doors, which are now sealed-off driver cabs unlike the old Ganz-Mavag and EE EMUs. Probably helped that the Tawa Flat tunnels were already large enough (being double-tracked) and the Matangi’s don’t have to use the Maoribank or Rimutaka tunnels though.

        2. J90, what are you talking about? The Matangis do have end-doors, and the Johnsonville tunnels were enlarged (floors lowered by up to 800mm) simply enable the Matangis to fit through. The tunnels were not made any wider and end-door egress is still necessary if a train gets stuck in one.

  8. Where in the world are battery powered trains like the proposed units being used?

    Seems to me that a technological test is being proposed. Everybody can quote a cock-up of a new technology’s introduction .

    My main concern is lithium batteries. We have all seen on you-tube clips what a piddly lap-top battery can do if not properly constructed/cared for. We know that Boeing spent months sorting out safety of the lithium batteries in its dreamliners, after years of testing and aviation-level design. Yet we have an un-tested carriage design proposed with a massive lithium battery being installed OVER THE PASSENGERS HEADS! Seems at the minimum pretty stupid and at worst similar to building a coal mine with only one entrance/exit tunnel.

    1. I’m guessing they won’t have to reinvent the wheel with what Boeing and others have already learnt regarding Lithium batteries. If they are safe to use on a plane they are probably safe to use on a train with two doors on the side of each carriage.

    2. First of all, the proposed acquisition and use of battery-powered EMUs in Auckland would not be the first use of battery-powered passenger rail vehicles in New Zealand. For seven years an Edison battery-electric railcar was used on the Little River Branch in Canterbury until its time was unfortunately cut short when it was destroyed in a fire. Different technology (c. 1930s), sure, but not like it hasn’t been done before.

      Second, KiwiRail occasionally used to run locomotive-hauled rakes of Ganz-Mavag EMUs from Upper Hutt to Featherston for the Toast Martinborough festivals. Between those stations the EMUs ran on battery power, particularly through the two tunnels in-between for lighting purposes. If there was going to be a problem with passengers using battery-powered rail vehicles, wouldn’t that be an issue going through the second longest rail tunnel in the country? Any battery can fail if there is a manufacturing defect, design flaw, improper maintenance, etc. and enough should have been learnt about Li-ion by now that their use in rail vehicles should be no more dangerous than most other common applications.

      1. Big difference between using batteries to sustain lighting power (as per Ganz Mavag EMUs loco-hauled through the Rimutaka Tunnel), and using them to supply traction power.

        And the battery railcar that ran Christchurch – Little river as far as I know ran one return journey each day and required several hours’ layover at each end to recharge. Technology-of-the-day of course. Would be different now.

    3. The traction battery bank in an IPEMU is likely to be a well established and tested Lithium chemistry such as Lithium Iron Phosphate (LiFeSO4). Rather than one of the more recent lightweight high density battery chemistries.
      The LiFePO4 cells are heavy.
      From the limited online CAF info it seems the actual banks of cells will be located underneath the battery car. A price of $441k was given as battery replacement cost.
      The above passenger head space is likely where the somewhat complex charging and control electronics are located although there could be batteries for some sub systems such as lighting, air-con, wifi, tv displays etc..
      I can’t find exact specs on the IPEMU so there could be some rocket science stuff there that has traction batteries squeezed into the roofspace.

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