A story a few weeks ago highlighted that lower North Island councils are frustrated that the government didn’t provide funding in the budget for new regional trains.

The Transport Minister has left the door open for 22 new electric trains, after lower North Island mayors kicked up a stink they weren’t funded in this year’s Budget.

The four-car trains would replace “vintage” units and quadruple peak-time services between Palmerston North and Wellington on the Manawatū line, while doubling them between Masterton and the capital on the Wairarapa line.


Now, Ponter and Horizons Regional Council, supported by 15 mayors, have written to the Transport and Finance Ministers after their $360 million Budget bid towards the $762m project failed.

They said they were surprised and disappointed.

“We are now working against the clock to replace our fleets of 50-year-old regional rail carriages, which will soon reach the end of their working lives,” the letter said.

“The tender process for new trains must continue unabated so we look forward to engaging with you on finding ways to unlock Waka Kotahi and other funding for procurement.”

The plan is to buy 22 four-car tri-mode trains – trains that are powered by electricity when under wires and by a combination of batteries and a fuel based ‘compression-ignition’ engine when off-wire – the exact type of fuel is not specified.

The cost also includes a variety of infrastructure improvements to support the trains and the additional services that are planned. The paper also notes that it is expected that over time as battery technology improves  it would extend the range able to be achieved, further reducing fuel use.

In response, the article says

Transport Minister Michael Wood wrote a letter in reply and said while the bid was unsuccessful due to competing priorities, ministers were mindful the long-distance passenger rolling stock was reaching the end of its economic life.

Service continuity was critical, Wood said.

He has asked Ministry of Transport officials, in preparation for Budget 2023, to continue working with the regional councils to look at the business case in more detail.

“This engagement may also consider issues of scope, cost share, and timing.”

It’s crazy the government won’t fund this, a project that aligns with government policy and the Emissions Reduction Plan, that has a benefit cost ratio (BCR) of 1.83, but is pushing ahead with the Otaki to north Levin expressway which had a BCR of 0.2 and that was before it nearly doubled in price to $1.5 billion. Also notable is that even with the expressway and optimistic assumptions, it is only expected to move about 22,600 vehicles per day by 2041 which is less than Waka Kotahi’s own suggested trigger for four-laning of forecast volumes exceeding 25,000 per day.

There are perhaps two good reasons for the government holding off funding and they are that

  • this should be national project rather than just a regional one
  • the government should include funding for additional electrification infrastructure thereby potentially changing the preferred train architecture

Let’s look at these.

A National Project

Wellington isn’t the only place that could do with some improved regional trains.

At the very least it would be useful for Te Huia to get some bi/tri-mode trains allowing more services to run and for them to use the wires within the Auckland region. That could also potentially allow Te Huia services to access Britomart and make use of the two platforms that are likely to be spare once the City Rail Link is up and running. It’s worth noting that the government have always talked about Te Huia being a start with further improvements to come over time. This could be a start to some of those longer-term improvements – there’s also this paper which looked into providing faster services along the route.

Additional trains could also be used to improve the Northern Explorer service between Auckland and Wellington. Currently just six services a week run – three each way and those trains are hauled behind an old diesel locomotive, even though 72% (and soon to be 75%) of the journey is under wires. New trains could allow for more services and perhaps even overnight services. There are other potential benefits too, for example because Electric Multiple Units perform better than diesel-hauled locomotives, it may enable services to stop at towns currently bypassed.

So why include trains for these other services:

  1. A larger order would be more attractive to international train builders, which may help fetch a better price.
  2. A single nation-wide regional train architecture could enable better efficiency, for example, having just a single facility for heavy maintenance, a common stock of spare parts and potentially even the ability to move trains between services if needed.
  3. It sets up a clear design should other regions want to consider services and depending on how many are ordered could even allow for some to be trialled.

And before anyone raises the issue of different power systems, the shortlist for Wellington’s business case even included dual-voltage options.

  • Option 1: EMU (1600V DC) + 1600V DC partial electrification + buses beyond Featherston and Ōtaki + increased services
  • Option 2: B-DMU + increased services
  • Option 3-1: B-EMU (1600 V DC + extra battery) + no further electrification + increased services
  • Option 3-2: B-EMU (dual voltage + battery) + 25 kV AC partial electrification + increased services
  • Option 3-3: B-EMU (1600 V DC + battery) + 1600 V DC partial electrification + increased services
  • Option 4-1: Tri-mode (1600 V DC + battery + CI) multiple units + no further electrification + increased services
  • Option 4-2: Tri-mode (1600 V DC + battery + CI + 25 kV AC provision) multiple units + no further electrification + increased services
  • Option 5: EMU (dual voltage) + 25 kV AC electrification over full current non electrified route sections + increased services

The main uncertainty with dual-voltage options that also include batteries and CI engines seems to be just whether there’s enough space on the trains for all the equipment needed. Either way that likely means more cost and I assume that’s something Wellington is unlikely to want to invest in given there’s not a lot of benefit in it for them.

An alternative to having dual voltage could be just to have a common design but in two fleets with each having different transformer equipment.

It would be easier to have dual voltage trains if we could ….

Extend Electrification

In a reply to an OIA I came across, Kiwirail included a high-level study they commissioned in 2021 on the cost to electrify four key route segments in the North Island. If all were completed it would electrify all lines that currently carry passenger services, the busiest freight route in the country, and extend electrification infrastructure into the freight yards in Auckland and Wellington.

What’s really notable here is that the consultants estimate we could get all of that for less than the cost of a single expressway. That seems like an absolute bargain.

In their response to the OIA, Kiwirail say:

We comment that the information in this high-level study is feeding into other work KiwiRail is currently undertaking – such as an indicative business case that considers further electrification, potential alternative technologies, and encouraging freight mode shift to rail in the decades ahead; and separate work around network improvements to support the business case that Greater Wellington Regional Council is currently working on around long distance commuter trains to Palmerston North and the Wairarapa.

So rather than electrification, there may be better economic options longer term.

Greater Wellington Regional Council is currently working on a business case for replacement commuter trains, with potential for them to be bi-modal. For those types of trains to operate there would need to be some infrastructure upgrades, including the further electrification of a small section of the line between Waikanae and Palmerston North.

We are currently in the early stages of looking at the feasibility of these required upgrades and there is no timeframe for further steps.

KiwiRail is exploring other options for low emissions freight ourselves, including tri-mode locomotive technology which only requires a partially electrified network to operate on. Tri-mode locomotives work by
using the existing electric overhead infrastructure where it exists and then use energy storage (battery) in between electrified sections.

The locomotive has a small diesel engine to use to charge the batteries if required too. This exploration of locomotive technology is also in a preliminary stage.

It feels like all the various pieces are sitting out there, just waiting on someone in the government to pull them together into a single vision that will significantly improve the rail network and the services on it while at the same time as reducing emissions.

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  1. The Northern Explorer is not yet running, It is back in September. And the cost of a one way fare between Auckland and Wellington is $219. At that price, most families cannot use it. As to the motorway between Otaki and Levin, both Labour and National support it. It seems there is very little local pushback against it and the politicians know that. Its not about rational economic and climate decisions, its about votes. And there seems much enthusiasm for Transmission Gully since its opening – although lots of trucks are now going along the old coastal route. We know trains are climate friendly but its an uphill battle getting support for the changes we need.

    1. This is a good encapsulation of a major issue with democracy. It’s a roadblock to evidence based progress.

      1. Evidence-based is always biased though. Democracy is still better than authoritarianism. At the end of the day “those who pay have the say”. If you need other people’s money to fund things, you have to make sure the majority support what their money is used for.

        If they replaced government with a AI-computer that pursued everything on evidence-based outcomes, it would likely determine the most efficient project would be to remove humans, thereby restoring the environment and avoiding the necessity to do anything at all.

        1. you mean the project that is underway at the moment – floods in NSW for the fourth time this year. Bound to remove humans sooner or later. No one will be able to afford the cost or the emotional damage.

    2. Even from a roads perspective Wellsford and Woodend can’t even get a bypass, yet Levin gets the gold plated version.

      1. Yep, the lack of bypasses in particular is just NZTA playbook 101.
        Pretend the only option is to wait for the mega highway bypass to come to town so you can include that in the justification for said mega highway.

        They could do bypasses of small towns. Eg the edendale realignment. Got SH1 out of town, improved a major intersection, added a passing lane, 15 million dollars. Only done there because there is no motorway bypass possibility in the remote future, and pressure from Fonterra.


        1. The problem with bypasses is that without some form of covenant/protection/restrictions in place local developers jump on the newly provided free infra and build next to it negating the whole purpose of the bypass.

        2. They can disallow properties which front the new bypass. So even if the bypass eventually sits in the middle of the urban area, you still have a road with almost no accesses that is suitable for through traffic.

        3. There is already a mechanism to mostly solve this realist.

          “Limited Access Roads” is the terminology. The NZTA get to refuse new accessways. A good portion of the state highway network is already limited access. There are thousands of grandfathered in crossings, and it seems like the NZTA is not strict enough when approving new ones sometimes.

          But in the example of these bypasses they’re basically a done deal. They put in side rope barriers and the roundabouts provide adequate access. There is also the option of left-only access when heading towards a roundabout. Then the opposite direction can be provided by going around the roundabout. The edendale bypass shows both of these at work.

          These bypasses are generally short enough that these these roundabouts accessible enough that nobody would desire to put in a random accessway, and nor would the NZTA let them.


    3. The points you make, sadly are correct. The Northern Explorer is targeted at tourists while InterCity buses already cater for some low-income people. (I know, I am one myself!) Most low-income people and others drive or fly

      It’s politically expedient for Labour and National to build motorways because most voters use them. Conversely, using trains between cities, worthy or not, is very much a minority activity.

      1. Yes those buses (and train) is a rather niche thing.

        You can tell from simple bean counting. How many seats are there on those bus lines per day? A couple of thousands? The Waikato Expressway alone can shift that amount of people within an hour.

        I have taken those buses a couple of times, I wouldn’t say it was bad, it wasn’t even that much slower than driving. But the need to book in advance is a crippling disadvantage compared to driving.

        1. The thing is that the buses and trains aren’t inherently a niche thing, but they are operated as if the are a niche product and hence, they only attract customers from a specific niche.

        2. @Sailor Boy Yes. It is specifically how things are run over here.

          A logical consequence of:
          – we spend a couple of billions of dollars on this expressway.
          – we could have spend a couple of billions on trains but we didn’t.

    4. Why should little old NZ worry about the climate, especally now that Germany and the US are going back into coal in a huge way, water we save won’t make any difference. Also there a war on at the moment which has blown all climate savings by rational countries out of the water.

  2. I am pessimistic that we will see the required long-term shift to better regional rail unless we also get people out of cars. In terms of the carrot and the stick, at the moment we have an articulated 40 tonne truck full of juicy juicy carrots for cars (Waikato and Kāpiti/Horowhenua motorways), and no carrot for rail.

    The natural constituency for rail is the non-drivers and there are just not enough of them. The required VKT reduction, road pricing, and RUC reforms are the brightest lights at the moment… will we see them come to fruition?

    1. And the mechanism to get people out of cars is to have them pay for the true cost of the road through tolls. Expressways at Otaki wouldn’t happen because collectively people would begrudge increased tolls because of a nonsense project.
      Where is the ACT party when you need them to talk about user pays?

  3. Wow, that is astoundingly cheap for all that electrification. I wonder why the Pukekohe to Papakura section is so expensive? quite a lot of trackwork?

      1. The new stations are different projects / sets of money from the electrification. Only the pukekohe upgrade is included in the electrification projects.

    1. $1.5 billion is cheap? How many people use these services, I imagine it would be a million dollars each.

      1. I think the question you should be asking is how many people COULD use these services, if they were fast, frequent and affordable. People love riding trains, they’ve just been forgotten about for so long in this country.

        1. 15 years ago I used to catch a train from London that was fast, frequent, affordable and diesel. There was a train every 10 mins or so, all very busy. Electrification would be the last thing to spend on, try fast and frequent first and see if people use it.

      2. Plenty of freight on the Auckland to Tauranga route already and a lot more expected as Tauranga benefits from the Auckland port can being kicked down the road.

    2. Although I’m not 100% sure, I presume that the costs for the P2P electrification probably includes the cost of resignalling the route to include ETCS Level 1 which has been installed on the rest of the railway in Auckland.

  4. Wouldn’t it be better to order off the shelf DMU regional trains and push on with electrification. This trimode/ICE/battery idea is going to be very expensive and difficult to fit into NZ rail’s tight restrictions on size and weight, not to mention the narrow gauge. Maybe Stadler Flirt type design with a diesel power car in the middle of the train that can be removed later to produce a pure EMU.

    1. The Stadler Wink and GTW do have a power car that is available for electric, electric/battery, diesel and now hydrogen fuel/battery capable.

      Alstom has the 4 carriage 218 seat Coradia Polyvalent H2 that is electric and hydrogen fuel cell/battery capable for inter-regional operations and the smaller 2 carriage 150 seat Coradia iLint for urban metro and regional operations. The Alstom Coradia iLint can be used a coupled sets.

      Both rolling stock suppliers would be able to modify their products to met New Zealand requirements especially if a DBFOM (design, build, finance, operate and maintain) style of public/private partnership if used for a national fleet.

  5. Declutter the design by ditching the Diesel engine, dual-mode overhead line plus battery will cover all reasonable service areas, with some work to add additional charging at terminus stations.

    Also keep rolling out OHL consistently until core of Wellington-Auckland-Tauranga is complete. Keep the team skills and supply chain of the group delivering Puke OHL together and move them onto the next section, etc. this will keep costs lower and predictable.

  6. DMUs now would be better than electrification never due to an inevitable change of government at some point.

  7. I hope it’s OK to include a notice here.

    Rail fan and academic Andre Brett is giving a talk at the Central City Library on Wednesday 6 July from 12 to 1pm.

    ‘New Zealand’s shrinking passenger railway network: Slow decline or hope for the future?’

    It’s free but you have to register.


  8. I expect Kiwirail and the ministry of transport want to see how this new hybrid technology develops overseas and not just for passenger trains but also for freight. If hybrid battery/overhead locomotives become common and economic then maybe full electrification of the whole route may not be necessary. I could imagine only some sections of track being wired. For instance the Kaimai tunnel or hilly sections could be wired and battery power could fill in the gaps. I think it’s called in motion charging but it’s very early days for this technology particularly for freight operation. Anyway this brings up the option of having locomotive hauled passenger trains as opposed to multiple units. This would mean we can continue using home grown carriages rather than overseas built multiple units it also means if the overheads is down for maintainence a diesel locomotive can be substituted. Also I can imagine a train with a diesel loco on one end and a battery/overhead loco at the other. The pure battery locomotive that are being developed in the USA are being used in multiple with diesel locomotives and are giving good fuel savings.

    1. Wiring is still worth it for the key routes in my opinion. I think we are a long way from battery powered freight trains from say Kinleith to Mt Maunganui.

      A freight train that runs on battery from Kinleith to Waharoa, and from Tauranga to Mt Maunganui on the other hand might be viable sooner.

      1. There could be a section on the Kinlieth branch that’s is electrified. But I tend to agree the bulk of the main trunk and Hamilton Mount Mainganui line should be electrified. One thing apart from the price of diesel and emission in favour of electrification is the far from stellar preformance of the relatively new DL locomotives. They could be used for less demanding and less time sensitive tasks. A log train breaking down between Woodville and Napier is much less of a problem than a train missing a ferry connection in Wellington.

  9. Is it feasible to converting Wellington from DC to AC, while rolling out additional electrification? Certainly ideal long term to all be one standard system.

    In any case I like the idea of the continuing electrification from once the Pukekohe line is done if not sooner & having a larger team doing the on going roll out.

    1. Feasible? Yes, cost effective? No.
      Better to just get dual voltage units and then as the OLE reaches the end of its life start replacing it with 25kV over time.
      The question is with the Wairarapa line do you extend it with DC or AC?
      DC cheaper and no plans for AC freight, but if you’re eventually going to change the whole network over then probably better to just do it as AC from the get go (or at least design it so it can easily be converted over).

      1. If there’s any plan for 25 kV AC from Wellington to Palmerston North it may make sense to use the existing DC fleet – possibly with changes to the interior – between Wellington and Masterton.

      2. Extend with 25KV AC overhead design and feed it with 1500V DC.
        Then any conversion ONLY requires changes at the substations.

        1. 1500vDC requires much higher currents than 25KV so the conductor wires are thicker and consequently heavier so the traction masts and foundations are larger than for 25KV Ac

  10. Well, there would be money for this, if we hadn’t subsidized the cycleways earlier! If we cut down the cycleways, businesses will have more customers from all the cars driving past and will be able to pay the taxes for more rail. In fact, if we replace rails with motorways before construction, people could go places faster and spend even more money! (/s if necessary?)

    1. More car parks would help grow business too. I wonder if Auckland could look to buy the 70,000 that Paris is taking out. I suspect with the new trade deal with Europe there are no duties.

  11. https://www.kiwirail.co.nz/what-we-do/projects/amp/papakura-to-pukekohe-electrification/
    Funding of $371 million for the 21 kms from Papakura to Pukekohe was received as part of the Government’s New Zealand Upgrade Programme = $371m ÷21kms =$18 million per km
    The distance Hamilton to Pukekohe 105 kms and Hamilton to Tauranga is 107 kms at $18 million per km the cost of electrification would be $1.855 million and $1.890 respectively. Grossly more than the $430M and $426M quoted in the table.

  12. It’s always somewhere between disingenuous and obstructive when unknown future alternatives are presented to the current known of overhead electrification. The biggest problem with this approach is that it provides cover for doing nothing, with nebulous future promises – ignoring the possibility that little may eventuate.

  13. The problem with this is that the1500V system requires very much thicker gauge overhead then 25Kv to deliver the same power. Watts equals volts x amps.

    Lighter overhead was the main justification for the move to 25kv.

  14. The Lower North Island Rail Integrated Mobility business case has opened up the discussion concerning the future of urban, regional and inter-regional passenger rail across the country.

    Between 1936 to 1978 New Zealand did have a regional and inter-regional passenger rail services using the Standards, Vulcan and 88 seat articulated railcars being additional to long distance passenger trains.

    If this country is serious about the re-introduction of regional and inter-regional passenger trains services in the 13 of the 16 regions that have currently have rail connectivity, this needs to done as a national plan using a standardised national fleet of 2/3 to 4/5 carriage bidirectional, railcars that are dual mode electric and sustainable environmentally friendly fuel/battery and/or sustainable environmentally friendly fuel/battery only railcar sets that would have the ability to operate on electrified and non electrified lines.

    The question is not if but when.

  15. I think it is unlikely that Wellington will loose its 1500V DC system before expiry of the remaining economic life of the Matangi stock. Another 40 years?
    So I think it is unlikely the 25kv system will be extended south of Palmerston North in the meantime. So the 4 car 1500V/battery/IC electric sets seem a good fit for the Wellington based regional sets.
    Extending the 25kv overhead into, and then beyond Hamilton to the Bay of Plenty would considerably increase freight capacity as well as resolve the Kaimai tunnel toxic fume problem.
    Taking any IC powered train sets into Britomart even with the IC unit shut down, still requires enhanced fire protection to deal with the combustible engine fuel.
    So best just get on with now, double tracked track straightening and swamp avoidance, with 25kv electrification, at least to Hamiton in the first instance.
    Increasing freight capacity and resilience alone with emission reduction should alone justify this investment.

  16. It may all be for less than the cost of an expressway Matt, but it doesn’t deliver a new alternative. The railway lines are already there and already available for use. So the $1.5b spend wouldn’t deliver any new routes. It would be better to spend the money on new trains that can just use the existing lines. Diesel/electric hybrids would be fine.

    But considering this government’s track record on delivering things, I have no doubt they will exit government having made absolutely no progress in this area. The far more important issues like housing, poverty, etc have gotten worse under Labour than they were under National and there’s every indication the government isn’t going to do anything to solve them.

    At the end of the day, politicians are figureheads. The country is run by civil servants, and they follow trends determined by treasury, who follow trends determined by big business and big tech at Davos and Bilderburg conferences.

    $14.7 TRILLION has gone into the pockets of the world’s billionaires since March 2020, on top of their pre-existing wealth, whilst the rest of us are told by the government that times are tough and we need to pay more for everything. That has happened precisely because government’s only deliver what the billionaires want, and within their framework. And that means not rocking the boat and making a real difference.

  17. I dearly hope there’s some work going on behind the scenes to pull all these business cases together into something that can be meaningfully progressed.

    A sensible strategy would be a 10-year electrification plan as above, in conjunction with a national fleet of tri-mode EMUs and locomotives that can operate anywhere in the North Island. Electrify a certain length of track every year, with tri-mode rolling stock using their diesel engines less and less as each section of electrification is commissioned.

    Construction contractors are crying out for an “infrastructure pipeline” – a steady, predictable supply of work. Well, this is one way to do it.

  18. An interesting discussion as ever but I’d like to add a couple of additional thoughts. Electrification brings a number of benefits. Several of these have been mentioned (emissions reduction and addressing the fumes in tunnels issue being two). One of the other benefits not mentioned here for freight is that a modern electric locomotive has significantly more power available than a diesel locomotive of a similar size. As an example the new Stadler Class 99 bi-mode can offer 6000kw under the wires (the ubiquitous Class 66 can only offer 2420kw) whilst only offering 1800kw in diesel mode. This difference can be significant when trying to navigate challenging terrain (i.e. hills), trying to maximise efficiency (or permit growth) by running fewer but longer freight trains or maintain speed whilst operating in amongst a metro passenger operation.

    1. The full report talks about this a bit. They say kiwirail could potentially use a single loco on any of its NIMT trains while still fitting in axle weight limits.

    2. Increasing the power of a locomotive does not enable it to haul heavier trains. Increasing the weight of the locomotive does. The maximum weight of a locomotive is determined by the number of axles (generally a maximum of 6) and the maximum permissible axle load (which is a function of the permanent way design). Wheelslip control is a given these days so the overall weight of a locomotive (irrespective of whether it is diesel or electric) determines the tractive effort and hence the mass of a freight train it can reliably haul over a given route.

  19. I doubt that. Electrics are more powerful than the diesels for sure but not so much more that they could cut NIMT trains to a single Loco.
    The Ham to PNTH section is limited to 1700 tonnes with two locos and normally 900 with one. Most NIMT trains are loaded right up near the limit at 1600 or 1650 tonnes. So they would always have a double Loco i’d say.

  20. To me, it seems the report was written without a broad enough perspective, passenger rail, road, air, water & freight air, road, rail, water are all part of the equation. IMO a primary efficiency/ emissions goal should be to have 25kV Overhead line (OHLE) for rail from Auckland to Wellington. The technology now exists to make this possible. There are examples overseas where electric trains had battery systems added to them. Hyundai Rotem and Furrer+Frey should be asked to investigate converting part of the Matangi FP/FT Wellington train fleet to battery power for the Wellington to Waikanae (NIMT section),dual pantograph by adding a 25kV pantograph for battery recharging. Initially 25kV charging at Waikanae, Paekakariki stabling area & central Wellington. (the 1600V pantograph would still allow these converted trains to use the remaining 1600V areas) This should enable a ‘Stage 2’, the removal of the Wellington/ Waikanae 1600V DC overhead, and build of 25kV OHLE from Palmerston North to Wellington/ Port, for existing & future electric freight locomotives & Auckland/ Wellington passenger rail. From old document info- the Tawa tunnels are likely to be high enough already to have 25KV put in with sufficient clearance. A ‘Non-lower North Island only’ specification of future NZ low emission regional passenger trains could then be to run/ battery charge under 25KV wires (or 25kV stationary point charge at station stops etc), onboard generation with sufficient space allocation to be flexible for future range expansion or technical change. One consideration for 1600V areas for 25kV battery trains would be warning systems/ geo-fences to ensure their 25KV pantograph is lowered for the low 4.5 metre 1600V lines (vs 5+ metres). Onboard ultracapacitors and between rail induction charging are two developing techs that could be footnoted.

    1. It could be feasible to separate the Wellington regional system into two distinct halves, and electrify the NIMT fully with 25kvAC, and keep the hutt and J ville lines as DC. Shift all the Matangi fleet to the DC side including out to Masterton, get new AC trains for Kapiti line.

      Not sure what that means for stabling and depots but the tracks are pretty separate already, just one extra link before the tawa tunnel.

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