Battery-Electric Buses: New Flyer

Two months ago, after my article about battery-electric buses appeared in CityLab, New Flyer reached out to me for an interview. Already in one of the interviews I’d done for the article, I heard second-hand that New Flyer was more reasonable than Proterra and BYD and was aware of the problem of battery drain in cold weather. I spoke to the company’s director of sustainable transportation, the mechanical engineer David Warren, and this confirmed what I’d been told.

Most incredibly, I learned at the interview that the headline figures used in the US for electric bus performance explicitly exclude heating needs. The tests are done at the Altoona site and only look at electricity consumption for propulsion, not heating. New Flyer says that it is aware of this issue and has tried not to overpromise, but evidently Proterra and BYD both overpromise, and regardless of what any vendor says, American cities have bought into the hype. In Duluth this was only resolved with fuel-fired heaters; the buses only use electricity for propulsion, which is not the majority of their energy consumption in winter.

Warren and I discussed New York specifically, as it has a trial there on the M42. The heater there puts out 22 kW of energy at the peak, but on the day we discussed, January 29th, when the air temperature was about -7*, actual consumption was on average about 10 kW. Electricity consumption split as 40% heating, 20% propulsion, and 40% other things, such as the kneeling system for easier boarding.

The battery can last many roundtrips on the M42, specifically a very slow route. Electric vehicles tend to do much better then fuel-powered ones at low speed in city traffic, because of regenerative braking and higher efficiency. When I discussed the Proterra trial with MVTA, I was told specifically that the buses did really well on days when the temperature was above freezing, since the battery barely drained while the bus was sitting in rush hour Downtown Minneapolis traffic. This pattern is really a more extreme version of one that may be familiar to people who have compared fuel economy ratings for hybrid and conventional cars: hybrids are more fuel-efficient in city driving than on the highway, the opposite of a non-hybrid, because their electric acceleration and deceleration cycles allow them some of that regeneration.

The current system is called OppCharge (“opportunity charging”), and currently requires the bus to spend 6 minutes out of every hour idling for recharge; the Xcelsior presentation shows a bus with a raised pantograph at a charging station, and I wonder whether it can be extended to an appropriate length of wire to enable in-motion charging.

The New Flyer examples I have seen are in large cities – New York and Vancouver. New York’s system for opportunity charging does not require an attendant; Vancouver’s may or may not, but either way the charging is at a bus depot, where the logistics are simpler. In contrast, in Albuquerque the need for midday charging was a deal breaker. When I talked to someone who knew the situation of Albuquerque’s BRT line, ART, I was told that the BYD midday charge system would require an attendant as well as room for a charging depot. Perhaps an alternative system could get rid of the attendant, but the land for a bus that at the end of the day isn’t that busy has nontrivial cost even in Albuquerque.

Even with opportunity charging, batteries remain hefty. Warren said that they weigh nearly 4 tons per standard-length bus; the XE40 weighs 14 metric tons, compared with 11.3 for the older diesel XD40 platform. Specifically on a short, high-ridership density like the M42 and many other New York buses, there is likely to be a case for installing trolleywire and using in-motion charging. In-motion charging doesn’t work well with grids, since it is ideally suited to when several branches interline to a long trunk route that can be electrified, but ultimately it’s a bus network with ridership density comparable to that of some big American light rail networks like Portland’s.

*In case it’s unclear to irregular readers, I exclusively use metric units unless I mention otherwise, so this is -7 Celsius and not -7 Fahrenheit; the latter temperature would presumably drain the battery a lot faster.


  1. David

    Just a note on “I wonder whether it can be extended to an appropriate length of wire to enable in-motion charging”

    According to the PDF, the pantograph is actually part of the dock and not the bus: “Pantograph lowered onto bus rails”

    Perhaps the roles could be switched, but that would probably require something like a traditional trolly bus or the Siemens eHighway:

  2. Michael James

    Standard batteries are just not up to the job and it is clear it will be a long time before they are. The real-world energy demands are a log order greater. Plus lithium chemistries don’t take kindly to deep discharge. Vandadium flow-batteries seem much more appropriate for this application, but there must be something not readily apparent as to why it is not in the running. Flow batteries cost more than lithium-ion but this shouldn’t really be a factor for buses or trucks, especially given their robustness, scalability and longevity. In fact, a full cost accounting would surely show them to be cheaper, especially with commercial vehicles that have a 25-year working life unlike cars whose value expires at about the same time their (lithium) batteries expire.

    I assume that Alberta’s objection to midday charging is that it amounts to a requirement to have excess buses to fill the idle time of those charging. Perhaps combined with the inconvenience of timetabling them so they are back at the depot at the appropriate time.

    Meanwhile Hyundai seems to be making a serious attempt at fuel-cell heavy vehicles, having done a deal with the Swiss for 1,000 of the 18-tonne trucks, including the hydrogen fueling network. The trucks require 8 large hydrogen tanks which provides up to 400km range. The Swiss are doing this for eco reasons so presumably the hydrogen will come from clean, if expensive, electrolysis of water rather than the atrociously dirty steam reformation of fossil fuels. It doesn’t seem this could be economically competitive with alternatives but it’s a beginning.

    On a related issue, Australian company Hazer Group is building a pilot plant for its claimed “carbon-free” process of producing hydrogen from natural gas. There is only corporate press releases (with “patents pending”) but it captures the carbon as pure graphite which is of such quality it can be sold as a valuable item. Not clear if that is enough to make it economically viable. It’s not even clear if the process is zero-carbon or just lower-carbon than steam reformation etc. Combined with CSIRO’s new membrane technology that enables using ammonia as an efficient hydrogen store, one can see how it could all come together but we can only hope we know within a few years.
    With Australia’s massive natural gas deposits (soon to overtake Qatar as biggest exporter) it could turn Australia from world’s worst carbon criminal to carbon-free energy exporter. Hah, that’s the plan but as usual this promising tech is being developed with peanuts: the clean energy research fund has just awarded A$22m to a bunch of projects but at only $1.35m each, it is only 0.0002 of Hyundai’s R&D budget of $9bn!

    • Max Wyss

      I know it is late, but I am not aware of any Fuel Cell deals in Switzerland. Do you have any further information (such as who the “Swiss” are supposed to be)?

      • Michael James

        Here it is (should be open access):
        Hyundai to send 1,000 hydrogen fuel cell electric trucks to Switzerland
        Bridie Schmidt, 24 Sept 2018.
        A fleet of 1,000 hydrogen fuel cell electric trucks forms the central part of a memorandum inked last week between South Korean carmaker Hyundai and Swiss renewable resource company H2 Energy.
        For five years starting from 2019, the fleet of 18 ton (16.32 tonne) fuel cell trucks will lead the vanguard of the commercialisation of zero emission trucks as they are provided to the hydrogen company in accordance with European regulations.
        Following on from Hyundai’s Tucson Fuel Cell which became the world’s first mass-produced FCEV in 2013, and the release of the NEXO FCEV in 2018, the agreement to provide the fuel cell electric trucks underlines Hyundai’s efforts to expand their exposure into the zero emissions commercial vehicle market.
        We first saw Hyundai’s fuel cell electric truck earlier this month, when the South Korean carmaker released an image of the aerodynamically designed truck with fuel cell powertrain in the lead up to IAA Commercial Vehicles 2018.
        Featuring a two-panel parallel hydrogen cell system amounting to 190kW output, the FCEV trucks, being developed by Hyundai are expected to deliver 400km range from full.
        8 large hydrogen tanks that can be refueled in as little as 7 minutes sitting between the cabin and the rigid body of the truck will power the fuel cell stack.
        Signing the memorandum (which also includes a reliable supply chain for renewable hydrogen) at IAA Commercial Vehicles 2018, head of Hyundai’s commercial vehicles division In Cheol Lee said that Hyundai’s ambition to commercialise the fuel cell electric truck is just the start.
        “We will continue to seek opportunities for expanding into other markets by carefully monitoring multiple factors such as fueling infrastructure and governmental policies,” he says.
        Upon receiving the FCEV truck fleet, H2 Energy will make them available to Swiss customers starting with members of the Swiss H2 Association.

        • Max Wyss

          Thanks for the link. So, on the Swiss side, it is a club with some members (among them, having joined only recently, one major logistics company). That club wants to import up to 1000 trucks until 2023, but its press releases do not mention any fixed orders.

          So, until I see the first of these trucks on the Swiss roads, it can not avoid the impression that it is just hype. But so what, I would not mind being proven wrong.

          On a technical detail, unless those trucks have a built in booster battery, they appear rather underpowered for Swiss requirements.

          • Michael James

            Yes, it appears to be a MOU signed at that conference. I think it reflects the need for a big car company to work with a customer at a certain minimum scale, ie. economics is entirely secondary to Hydundai. I just can’t see hydrogen storage as compressed gas in tanks as a workable system, ie. other than prototypes. But Hyundai may be trying to get the vehicles out of the starting gate, and betting on one of the various technologies for storing hydrogen maturing in the meantime–presumably the same trucks and same fuel cell could be retro-fitted with this new hydrogen storage system. I presume the same is true of Alstom’s hydrogen train.
            On the power issue I agree and reckon it might be an error. 190kW isn’t enough to power a 16 tonne truck as claimed. As the iLINT train shows, fuel cells of appropriate size exist and those 8 big storage tanks of Hydundai’s must surely be able to provision such a fuel cell; the iLINT is a version of the LINT-54 which has 630-≈900kW diesel traction. Incidentally iLINT does have Li-ion batteries as part of the regenerative braking system so one would think any fuel-cell vehicle will have them too.

          • Tonami

            Regarding the specs. All FCEVs have a battery booster like hybrid gasoline cars to handle power spikes and regenerative braking. Toyota’s own FCEV truck uses 2 Mirai fuel cells stacks producing a total of 228kW, but the Truck is driven by an electric motor rated at 500kW boosted by a 12kWh battery. The Mirai has only a 1.6kWh battery lifted from the Camry.

            From this report

            The system produces 190 kilowatts of power, and an electric motor makes the equivalent of 465 horsepower and 2,500 pound-feet of torque. The truck is capable of up to 400 kilometers of range, or about 250 miles. Its hydrogen tanks can be refilled in seven minutes.

            This Hyundai truck has a 347kW motor and a 190kW fuel cell stack. If we use the Hyundai Nexo as a reference, it has a 95kW fuel cell, a 135kW motor and a 1.56kWh battery outputting 40kW. It can be observed that the truck uses two Nexo fuel cell stacks (2*95kW) and 4 Nexo battery packs (4*40kW) for a total output capacity of 350kW.

            Here is a quote regarding the iLINT specs:

            Alstom’s iLint hydrogen train is a hybrid unit that makes clever use of a 225kW traction battery to supplement the power of its 200kW fuel cell to give the same performance and range as a diesel multiple unit train.

            and more iLINT coverage and details from

            As for feasibility, this truck is being pushed by Hyundai to be out there and hedge it’s bets just as the iLINT is being pushed by Linde Group as a way to secure a future market for their gas business.

          • Michael James

            Tonomi, that makes a lot of sense. Tx.

            The economics, at least in capital costs, must be a struggle. The driving force is the 10,000 km of regional rail in France (and Germany) that is uneconomic to electrify. Though one wonders about the In-Motion-Charging concept, or while at stations, plus third-rail power for a few hundred metres around the station (most power requirements are in getting the train moving)? But I guess that is another capital cost that no one can try to justify for such low-trafficked routes. And developing a hydrogen train supports industrial capacity that will be applied much more broadly.

  3. Herbert

    IIRC they want a “recharge in motion” system in Berlin on some routes.

    Of course electric buses still bunch and there are quite a few bunching bus routes that would be prime targets for railstitution if there were the capacity to do so. Apparently the issues besides NIMBYism have to do with an overburdened civil service in tree planning department that had been cut in the early 2000s. Even though there HAS been near constant lip service to west Berlin trams since the 1990s what’s actually gotten built is embarrassingly little. Heck, there’s even Bauvorleistungen that’ll likely go unused like tracks at Leipziger Straße or Oberbaumbrücke…

    • Max Wyss

      It depends, but comparable. However, it is the batteries that are sensitive to low temperatures.

  4. Martin Wright

    Good that you have been able to get inside and talk about real detail, rather than hype. I’ve been tweeting for some time about the high proportion of energy consumed for HVAC (e.g. in the context of the Moscow battery bus campaign) but the figures you have discovered have surprised even a cynic like me. That said the ratio between heat and propulsion in New York may be exceptional because of low traffic speeds and therefore low propulsion consumption. In other, less congested cities, the ratio between heat and movement may be closer to 50:50.

    With regard to charging, Vancouver is installing opportunity charging stations at the terminals of its route 100 right now. It may be that they will also do depot charging as well but the scheme is definitely aimed at rapid charging at the end of routes.

    Finally, I don’t follow why you think that In Motion charging doesn’t work well with grids. Isn’t the issue the intensity of service rather than the shape of the lines? If the grid consisted of routes with low frequency service, say every 15 minutes, then I agree that there wouldn’t be the economies of scale to justify wiring. But some cities may have a grid system where individual routes are high frequency e.g. every 5 minutes or less, where wiring could be justified. I must have missed something.

    Thanks very much for an interesting and almost groundbreaking article. Few people in the media (even the transit media) in the USA seem to want to go beyond the PR releases and the Musk-style presentations and look under the hood, so to speak.

    • ckrueger99

      One grid candidate for trolleybuses with IMC surely has to be Montréal. With world’s cheapest electricity, brutal winter cold and a pretty dense, high-frequency grid in some areas, it seems perfect.

      • FDW

        SF is another major candidate. There are a number of Diesel lines that already spend a large amount of time under trolleywire that would benefit from using it (Like the 2, 7, 9, 10/12, 43, 47), and a number of Trolley lines that could be extended off-wire to better terminals (Like the 1, 6, 14, 22, 24, 30/45).

  5. adirondacker12800

    Specifically on a short, high-ridership density like the M42 and many other New York buses,

    Just bite the bullet and wire up the whole island. With enough battery to get around the inevitable street closure. Maybe even scoot back to the depot when there is a blackout.

    What about the PABT, Lincoln Tunnel and long stretches of highway leading up to the bus lanes? Get the suburban New Jersey buses electrified east of the Turnpike it would cut a lot of pollution and noise. And the express buses in Queens. Got wire in Hudson County for the Manhattan buses the local buses could use it. Enough wire there could be niche users like newspapers, USPS, UPS or FedEx. How may trucks does UPS send from Newark Airport that would be near wires with a smallish system?

  6. Tonami

    Shenzhen’s full BEV bus conversion has helped propagate the hype further. But that has more to do with the provincial government promoting their local champ BYD than sound technical reasons.

    Beijing still has not gone all in on BEVs yet rather converting their busiest BRT routes from diesel to Trolley bus. And there is yet to be a comparison report out of Shenzhen on the performance of the new BEV busses to the old diesels. I suspect the fleet was increased significantly to keep up with schedules. They could have gone with trolleybuses for very busy routes, but they went with what BYD had in stocks and served as the perfect global marketing platform for BYD.

    Regarding the heating, I don’t know how much can be saved using Toyota’s vapour injection heat pump found in the prius prime.
    Toyota claims 63% energy savings and working range up to -10 degrees C.

  7. Eric Doherty (@Eric_Doherty)

    Well done! This is an important contribution to understanding what different types of electric buses can, and can’t, do. However, I have a minor quibble with one statement. “In-motion charging doesn’t work well with grids” is not supported by the linked article. It is quite correct that the cost can be lower with a trunk and branch system, but that introduces a serious reliability problem (what happens when the trunk charging road is closed because of a fire, police incident etc). Battery trolleybuses work best in cities like Zurich where there is a grid of charging roads – if any one charging road is inaccessible buses can be re-routed to other parallel lines. Great public transit has to be reliable, and reliability is worth investing in.

      • Max Wyss

        The trunk road will not be closed at its full lenght. Or, if it is so, it won’t be for a long time.
        For a short closure (some 300 meters), I have seen an examples. The trolleybuses are all equipped with remote controlled lowering of the poles. At the begin of the deviation, the driver lowers the poles and runs on auxiliary power (battery or small diesel motor-generator group) around the obstacle to the next stop. At that place, an agent of the operator raises the poles without the need for the driver to get out of his seat.

        The reason for the statement that a trunk road electrification is synergies. More vehicles can share the same infrastructure.

        Actually, in Zürich, there is currently one sector operated off-wire, and this sector is about 500 m long and contains a rather complex installation at one end. This section is served by two trolleybus lines. Otherwise, Zürich has only limited line overlap in the trolleybus network. The expansion projects relying on BTBs will, however, have some use of existing electrified stretches, but still have new wiring (such as a 500 m long 8% grade).

  8. Barry Lewis

    We completed our due diligence following a years worth of study and meetings in relation to the battery electric bus market – please find enclosed:

    In addition to what is found in this report, we also have to consider safety-related impacts and what we found both during our due diligence and thereafter cannot be ignored. Proterra, for example, are or have been under recall while attempting to use litigation funding through Clean Air Act violations including the VW settlement.

    If CMVs are not meeting federal regulatory requirements including Federal Motor Vehicle Safety Standards (FMVSS), especially considering the source of the VW settlement funding, then units that do not meet FMVSS should not financially benefit from litigation funding because of CMV units do not meet USDOT regulations and laws then they are not able to be legally allowed on public roads.

    And if they are not allowed to be legally allowed on public roads then they are not able to reduce the carbon footprint in any geographical market and thus are not reducing diesel emissions.

  9. Martin

    There’s probably opportunity to add charging wires in areas where bus goes uphill to both charge battery and preserve it for easier terrain.

  10. Pingback: Michael Liebreich’s Hydrogen Ladder Debunked –

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