In the debate over light rail in Auckland, opposition to it generally falls into two camps

  1. that we should build heavy rail instead
  2. that we can just use buses, especially new technology buses.

In this post, I want to focus that second camp and particularly on that last part.

The need for something to be done to improve access to the city centre is increasingly clear. Over the last decade alone, bus use in Auckland has increased from around 42 million trips to 65 million trips, a 52% increase. Much of that growth is to the city centre where combined with more trips on trains and ferries, now more than 50% of people every morning arrive in the city by public transport. With the number arriving by car about the same, it means that all growth in trips to the city has come from increases in the use of public transport, walking or cycling.

At various times of the day there are often long queues of buses streaming into and out of the city. All it takes is a slight change or disruption and busaggedon occurs, like it did last week in the image below. This is only expected to become a more common sight in the future as the use of PT continues to rise.

Whilst the need for change is now acknowledged, by most, how this is done remains a point of contention. We’re continuing to hear that some within our various transport agencies are wanting bus-based solutions. The primary reason for their opposition to light rail is the cost of building it. To avoid the cost but also provide more capacity than normal buses, the current fascination is a concept out of China dubbed ‘trackless trains’. In essence this is an electric, articulated, guided bus.

The idea has been getting plenty of press recently but is really just the latest in a long line of ideas to repackage existing bus technology and give it a new look and a new name. It’s easy to see why the idea is appealing to many, it looks almost identical to modern light rail vehicles, has a lot of capacity but is much cheaper to build/install. The idea seems almost too good to be true, and it might just be. Here are some of the reasons sticking with light rail, as planned, is likely to be the safer option

The risk of a technology cul-de-sac

The aspect that makes this different from most buses is that it is guided by a set of lines painted on the road. Guided buses aren’t a new technology and there are various different ways of doing it. There are a couple of mechanically guided busways, such as Adelaide’s O-Bahn, that use guide wheels against a kerb to keep buses on track. A couple of systems use magnetic sensors embedded in the road to guide a bus. There are even already optically guided buses, such as in Rouen, France, that like the trackless train proposal, uses painted lines on the road to guide buses.

A major concern with many of these systems is that compared to light rail, many of these systems are relatively new and not widely used. Some have already proven to be too unreliable have had to be pulled out. For example, many of the magnetically guided busways have been removed because they were unreliable and an optically guided busway in Las Vegas was removed because it was found to be too difficult to keep the markings clean.

This is further exacerbated by the fact that many of these systems tend to use proprietary technology only available from a single supplier. That creates a huge risk of lock in that could come back to haunt us down the road, especially so if the technology is no longer supported. By comparison, there a heap of suppliers to choose from that make high quality light rail vehicles.

While the examples mentioned all existed, the has been no shortage of late of other fantastical, and normally stupid, ideas. Let’s not forget the straddle bus which turned out to be a scam, or the bizzare gyro bus, or any number of other future visions being cranked out by various companies.

Auckland has enough issues as it is, we can’t afford for Auckland to be a Guinea Pig for unproven new technology

Capacity claims don’t add up

The press for the trackless train claims the vehicle can hold 300 people. This seems highly unlikely given the vehicle is only about 30m long. As a comparison, AT say that a 66m light rail vehicle will hold up to 420 people. The interior of the vehicle doesn’t suggest a huge amount of standing space either and a capacity of 180-200 people seems more realistic.

But even if it could hold 300 people, it’s not enough, which is why AT are going for higher capacity vehicles.

You can have too much frequency

One answer to capacity constraints would be to increase the frequency but that brings about its own issues. One of the features of the plans for light rail are to use signal preemption so that the vehicles get green lights all the way down Dominion Rd and the city. But this doesn’t work if frequencies get too high or other roads, like Balmoral Rd, would never get enough time in a phase. That then puts you back to the situation we have now where buses can get caught at lights and end up bunched and then platooning down the bus lanes.

The frequency issue is even more important in the city where Queen St is set to become a transit mall. One of the advantages of Light Rail, with slightly lower frequencies, is that there will generally be plenty of time when there’s not a vehicle in sight and it will be super easy to cross Queen St. More frequent buses to make up for capacity limitations will make it harder for pedestrians and so compromise on the goals for the city centre.

It might not end up that much cheaper

The cost is the big selling point for ideas like this but it’s possible they don’t end up that much cheaper in the long run. The main reason light rail costs so much is the need to dig up the road and strengthen it to handle the weight of the light rail vehicles. These buses, like light rail, are big and heavy pieces of equipment. Driven n a normal busway or road this may not be such an issue due to slight variations in the location within a lane that different drivers have. On a guided busway though, the buses will be in exactly the same location each time, day after day, year after year. This could lead to the need to more regularly repair the surface or potentially even strengthen it just like we’d have had to do with light rail.

Furthermore, while disruptive, sometimes it can be worth digging up the road anyway. One of the benefits discovered from building light rail on the Gold Coast was that by necessity they had to replace a lot of aging underground infrastructure. That meant they were able to replace infrastructure like water pipes it with modern, higher capacity versions which in turn unlocked more development capacity.


I do think that this technology is promising and definitely worth keeping an eye on, but I’m not convinced that Auckland should so quick to jump on the bandwagon. Let’s at least wait till at least a handful of cities have successfully rolled this out and ironed out all the kinks. Let’s also wait till there are multiple suppliers with inter-operable systems. Unfortunately, even without the capacity/frequency issues that I think would be an issue for the city centre, I don’t think Auckland can afford to wait. We need to get on fixing transport in this city and so should get on with installing light rail as soon as possible.

Where I think this technology, or something like it, could be particularly useful is on some of the non-city centre rapid transit routes. For example, running along the Eastern busway to Botany and Howick, from the airport to Manukau and then Botany. Perhaps also some of the slightly lower isthmus routes like Sandringham and Mt Eden Roads.

Share this


  1. I definitely agree with the sentiment when it comes to those all those bus-like technologies, but I do wonder if there’s a place for battery/capacitor operated light rail in the CBD. It would definitely reduce the visual clutter associated with running the overhead wires, could also make the construction cheaper and faster.

    1. Pshem – Auckland isn’t looking at OLE systems (at least from their renderings – looks like they are looking for an inground solution or battery system with OLE only for the non- road sections.

  2. I had Deputy Mayor Cashmore ask me the same question last Tuesday at the Planning Committee. I said No owing to capacity and corridor constraints between Manukau and the Airport. Given maintainence would become and issue as well you might as well run LRT down the Southern Airport Line especially as it meets up with Puhinui Station (Southern and Eastern Lines, and Regional Rapid Rail) and Manukau Bus Station (the main bus station in the south). Dig once, build once first time every time.

    The presentation and the RRR presentation can be seen here:

  3. I get the impression that this article was written from the point of view that “trackless trams” are bad and tried to set out to prove this premise.
    You failed to meantion that the particular trackless system referred to uses both the painted guide lines and road sensors to guide it. It is designed to allow the driver to manoeuvre it round obstacles and even down unmarked roads if required.
    The original article about the this system also discussed the ability to add or remove cars so the units could be 2,3 or 4 cars long (I got the impression that even more cars could be added although the size could become a problem on city streets)
    While I’m not saying that this or another, trackless system is the answer for Auckland, I do believe we should be looking at all potential solutions with an open mind and not try and direct the conversation away from options that are new because we personally don’t like. Them.

    1. I’m not saying they’re bad but they are unproven and many other systems have failed so caution is needed. The problem is that every time these ideas come up, those opposed to building proper PT in Auckland, people in various agencies (often Wellington based officials) jump on the idea and want more investigation, which inevitable ends up finding that the original solution was best but we’ve just wasted another year. It’s a predatory delay tactic.

    2. Although agreed, its frustrating that these keep coming up, even though they have been looked at multiple times already.

      Yes there are advantages and uses for both, but in Auckland current situation, they have far to many disadvantages. Not only are they relative new, and therefore have reliability issues as mentioned in the post, but the capacity just does not compare to a tracked system at this stage. I also highly doubt they are in-fact a cheaper alternative. Again all this has been mentioned in the post.

  4. The article reads as though the answer is predetermined, LRT. But the advantage of light rail is not the steel rail, but the combination of dedicated route, larger unit capacity and access control giving shorter dwell times. No reason some variant of BRT can’t do all of these

    1. But a dedicated route for some kind of bus involves building infrastructure, same as rails, but with none of the advantages of rails- increased efficiency through lower friction etc. And the downside of dedicated bus infrastructure is because it looks like a road, it’s very tempting for people to suggest allowing taxis/electric cars/normal cars to run in it too.

  5. I agree with your conclusion.

    Whatever future PT holds the vehicles used in the future has to be with a formula that goes something like this:

    Low maintenance
    Relatively inexpensive to run over its life span.
    Nil emission (doing something real about Climate change to say the least)
    Long life
    User friendly (low floor, smooth ride, maximises its interior for passengers, something current bus design fails to do)
    Fast (or comparatively compared to present day)
    Flexible – as in capacity can be added or removed easily but without requiring an extra operator/driver each time

    On the first 4 points the vehicle must be electric and this rules out diesel or any other internal combustion motor
    On the 2nd and 4th points battery only must be avoided as this is neither long life nor cheap
    But in area’s where light rail cannot be justified financially, electric buses should be used and of course the technology has been around for decades.

    In short something that runs on its own road, tracks, because by doing so you avoid large wheeled units that require long suspension travel, that is synonymous with a bus or a hybrid thereof and can have units added or subtracted as per a train.

  6. I think that some people who suggest that [insert hypothetical future transport techology here] is the solution to congestion/public transport actually don’t want to invest in public transport and by suggesting something in the future they feel they can justify avoiding doing anything now. *cough* Simon Bridges *cough*

  7. This chinese system is fundamentally a good multi-articulated electric bus with an ‘urban’ configuration with level floor, multiple double doors etc. We should probably use more of those, fancy looking or not.

    However there is one overlooked but extremely useful innovation in this system we haven’t seen in other advanced buses: the fact that it is double ended with a driving cab at each end. This is extremely useful a terminal stations, particularly places on street in dense city centres. The space required to turn buses around, via a huge roundabout or a ‘drive round the block’ route, can be incredibly expensive and impactful, and a huge source of congestion, unreliability and operating cost.

    A bus that can pull into a stop, then head straight back out the way it came, would be revolutionary. This combined with high capacity per vehicle/relatively low frequency is one of the great benefits of light rail. While I agree Auckland should not be the test bed for anything new, we should be rapid adopters once a system is proven in service. My view is watch this space very closely.

    Also I might add some people have been calling this driverless, its not, but it does have most of the hardware systems to become driverless in the future. Currently it is only guided and requires a human driver in control at all times. From what I understand the optical guidance is mostly used to precisely align the bus (do we call is a bus?!) to the platform to give low gap level boarding.

    1. I agree with you. I think this system should be looked at closely, in view of building dedicated road lanes and/or busway systems like the Northern Busway, whether it is in Auckland, Christchurch, etc.

      Watching the You tube video ( ), I could see this working in Auckland initially from the City to Airport, if it had its own dedicated road lines from the city to Mangere and a dedicated bus way from Mangere to the airport which is part of the proposed city to airport light rail system.

      I wonder if the Government, NZTA and AT would turn down an offer, it the Chinese were to pay for a city to airport system to prove it will work, since Chinese banks and investors are keen to fund major infrastructure projects in NZ?

    1. Indeed, calculations in our part of the world are usually based on standing passengers at 4 people per square metre. In Asia and other places they use up to 8 people per square metre.

      On a transit vehicle that has the majority of the floor area dedicated to standing, that simple shift can double the ‘rated’ capacity of a vehicle.

      Axle loads are an issue in NZ, we’re technically not allowed to load our double deckers up to capacity because the gross weight of all those people exceeds the axle limits.

      1. You could probably get around this axle limit by converting trucks that carry regular old shipping containers into passenger chicken coops?

      2. This is something people don’t realise, a fully loaded double decker bus has higher axle load than a fully loaded H plated truck (due to overloading). Need to either design a pavement to handle this load, or a track. Either-way its not cheap.

      3. Yes saw a packed full north bound train at Papatoetoe go “out of service” this morning at 7:43am due to being full enough it appeared (don’t’ know if it was southern or eastern). Was pretty full but wasn’t standing people at the ends etc and not that tightly packed.

  8. One thing that is always overlooked when comparing these things is permeability. Although this is very much a perspective influence on peoples decisions, when the public look at non-tracked solutions it gives the impression council can easily change things / routes etc as they feel. Where a tracked vehicle gives the impression that the route will remain for the foreseeable future. The key here is this encourages more intensification around surrounding land use on LRT routes.

    As some have mentioned, the post does read as if it is justifying a predetermined point of view. In saying that, I fully agree with the conclusion. There are benefits of both tracked and non tracked transport, to me the greatest benefits comes in the indirect benefit of land use confidence provided to developers. Something that non-tracked transport cannot provide to the same extent, unless its a northern busway type investment (in which you have the same disadvantages of a tracked system without the efficiencies, e.g. road space taken up).

    1. I’m pretty sure the Straddle was a giant failure, or rip off, or both. Would be keen to know more, but I did read that it crashed into cars, etc, caused mayhem, and that the whole thing was a farce. Pretty much as expected, but more than happy to be proved wrong!

  9. I don’t think in terms of cost savings, I think in terms of increased benefit. For example, if using these buses we could do 10 lines for the price of 1 LRT line, then the buses probably give more of a gain overall. Yes there would be a lot of compromises, but surely giving 10 times the people access to good PT is better than 1/10 to great PT.

  10. Good article Matt, and an interesting glimpse of just *part* of the baffling array of possibilities that get presented as solutions to transport problems. Presumably monorails, personal pods and narrow-track vehicles are still viewed by some as the answer we’ve all been waiting for.

    However there is one basic guideline which I feel we should not lose sight of. This is that mass rapid transit works by-far the best, and also avoids a multitude of safety and amenity impacts, if it runs on its own exclusive right-of-way. This rules out anything that shares space with other traffic, pedestrians or cyclists. Such sharing can work fine for non-rapid, lower-density transit, but we must be wary of assuming that an exculsive right-of-way can now somehow be dispensed with from modern public transport applications.

    When considering social and environmental impacts as well as speed and capacity, the most successful and effective mass transit applications are urban metro systems which run in exculsive corridors, either underground, elevated, or fully-fenced.

    If there are advantages in swapping steel rails for concrete strips with dotted lines then by all means let’s consider this, but the supposed cost-advantages of these alternative systems over traditional rails are likely to evaporate in the basic necessity of providing that all-important exclusive right-of-way that proper mass rapid transit needs.

    1. This is why I think Dominion Rd should largely be built as cut & cover rail.
      Exclusive right of way allows for speeds greater than 50km/hr.
      Increased vehicle, pedestrian, cyclist safety
      Stations are inherently weatherproof.
      Tunnel also provides service corridor for utilities, water, power, comms.

        1. New Zealand’s massive mistake, as with much of the world since the shift to motordom, has been its failure to plan and reserve PT corridors through urban developments. Had this been done, then installing quality rapid transit services would be as cheap as chips. Although a network of thoroughfares exists in the form of public streets which can also support PT services, these are a poor-substitute for dedicated rapid-transit corridors.

          We squandered the opportunity and as Nick R says, we are now faced with $1bn/km costs for things like the CRL (though bear in mind this figure includes much more than just the basic tunnels; threading a route through the ‘burbs instead of the CBD would likely be much cheaper per-km).

          I suspect we will eventually have to bit the bullet and do it, just as the major Australian cities have done or are still doing. But even if we can’t afford it now, we could still be planning and designating PT corridors for future use. If we were smart.

          That’s how motorways can be bulldozed through, often with little to stop them.

    1. It’s usually because the buses need to turn left or right, to pull into or leave a stop, or to move around another bus that has stopped for passengers. In the case above, you have all of the above happening.

      In most cases the bus lane is a nominal kerbside thing that runs between, but not through, intersections… seemingly designed to avoid distrupting traffic access to intersections more than anything else. Some of the time it is faster and less disruptive for the bus driver to not use the lane, a lot of the time there simply isn’t a bus lane to support the route the bus must take.

  11. Just let us get on and build the *insert expletive here* LRT system already with proven solid technology with huge capacity. No more delays and useless pondering on these half useless pretending to be LRT buses.

  12. Why should Auckland try and lead with new technology when it’s already 30 years behind other major cities and a simple catch up with proven tech would bear massive improvement?

  13. One thing that has only briefly been mentioned is that a steel wheel on a steel rail has much lower rolling-resistance than rubber on tarmac/concrete, therefore much more energy-efficient.

    1. Indeed Robin, that’s one of the reasons light rail has low opex, using (domestically-generated) electricity and less of it than buses burn diesel to trade the same distance.

      Even kids can get the difference – set up a crate of water bottles alternatively on rubber wheels (several kids struggle to move it) and rails (one kid can move it easily).

      Why is it, then, that we are so allergic to the capex to get urban transport right? In certain corridors (yes, such as Dominion Road to Onehunga, Mangere and the airport), light rail is a sure fire winner. Let’s get it done!

    2. The fuel consumption vs. electricity consumption is a small factor, and the relative difference between rolling resistance is a tiny factor in operating cost. Practically speaking even a dumb old diesel bus running a bus route is a very fuel efficient machine with very low consumption/costs per passenger.

      By far the greatest factor is actually the staffing rate per passenger, or in other words the capacity per vehicle. Large vehicles with lots of people on board are very efficient to run.

      Put another way, compare a 300 passenger electric bus with rubber tyres and a 300 passenger electric tram with steel tyres, on the same route and conditions, you’ll have negligible difference in operating cost.

      1. I would have thought that a bus would have higher rates of wear and tear on things like shock absorbers (due to road surfaces being not as smooth as rail), tyre costs would be a considerable cost compared to steel rail, road surfaces would need more maintenance as well compared to steel rail which has a far far greater lifespan.
        Granted these aren’t necessarily a huge difference in the overall scheme of things but they do make a difference to the ongoing opex.

        1. Back in Victorian England (c1870) they went from horse-drawn buses to horse-drawn trams. The same horse could pull twice the load on rails.

Leave a Reply