The inaugural New Zealand Transport Fuels Summit was held at the end of October, and the blog was invited to attend. I was able to make it to one of the two days, and I’ll try to write up some of my notes in the future.

One of the speakers was Iain McGlinchy from the Ministry of Transport, who gave a presentation on the New Zealand vehicle fleet. It was full of interesting insights – see below, or Iain’s Powerpoint for more (and much of the data is available via the Ministry’s Vehicle Fleet Statistics).

It’s often said that New Zealand has an old and inefficient vehicle fleet – but things aren’t quite as they seem. Yes, our cars are a bit older than in many other countries, averaging 13 years (vs 11 in the US, 9 in Australia and the EU, and 8 in Japan). That’s mainly down to the large number of cars we import second-hand rather than new – these mainly Japanese imports are usually around eight years old when they arrive. In particular, the ageing process is driven by the large number of cars built in 1995-1997 and imported in the early 2000s. We’ve got masses of them, and they’re still around for the most part.

What about the “inefficient” part? Iain notes that new cars tend to be safer (better features, etc) and do better in terms of particulate emissions, but “there is very little evidence that age and fuel economy are linked”. The amount of fuel used seems to come down to the number of vehicles in the fleet, and it “appears other variables, like [the] state of [the] economy, (or changes to fleet age) are not strongly affecting fuel use”.

Vehicle fleet and population

Old cars do tend to have less efficient engines, but they’re also smaller and lighter than new cars, and they tend to do less travel. Overall, Iain thinks that “on average, if we had a younger fleet (as a result of actively getting rid of our existing older vehicles) the resulting fleet would probably have a larger engine size and travel further than our current fleet… actively intervening  to create a younger fleet to reduce CO2 emissions, would probably not work”. So, no cash for clunkers then. A lot of people don’t understand the inertia of a fleet with 3.2 million vehicles that tend to get driven for 20-odd years and do 200,000+ kilometres in their lifetime (driverless car advocates take note).

If we do want to reduce emissions – and I certainly think we should – then it could perhaps be done by encouraging cars to be scrapped and not replaced. Iain: “if fleet size shrinks as older used vehicles are scrapped then fuel use may also fall”.

One thing I found particularly interesting was Iain’s data showing that new cars claim to be more fuel efficient, but often don’t deliver in the real world. In NZ, on-road fuel use remains stubbornly around 10L/ 100 km, despite supposedly more efficient cars being sold. Here’s the data for Japan.

Japanese fuel economy

Essentially, vehicles have always tended to use more fuel on the road than they do when they’re being tested. But the performance gap has gotten larger (and Iain also shows this for a number of European countries). Car manufacturers are becoming very adept at designing cars to do well in the tests, but not on the road.

Iain also argues (slides 36-37) that there doesn’t seem to be much of a relationship between petrol prices and vehicle travel. I’m not sure I fully agree. There’s inertia to people’s driving behaviour too, and it can take several years for the impacts of a price hike to become fully clear. I don’t think the tailing off of vehicle travel in the mid-2000s can be explained by much else except the massive rise in petrol prices – it’s not like the government started investing in public transport or anything, right?

Iain also asks the question that if most of our cars come from Japan, and the cars there are getting more efficient (and they are, despite the “gap” above – there are various incentives and subsidies in place there for hybrids and other efficient cars), will NZ’s fleet get more efficient too? The answer is, not necessarily. Japan favours small cars and hybrids, whereas here in NZ we continue to import medium/ large cars and SUVs. And hybrids tend to stick around for longer in Japan, due to the incentives, so it’s hard for NZ car importers to buy them at competitive prices.

Finally, Iain wraps up by discussing things that could help improve New Zealand’s fleet fuel economy/ emissions/ safety and so on. These include hybrids, Intelligent Transport Systems (not so sure about these; people can view this kind of stuff as an invasion of privacy or civil liberties, which is why we have so few speed and traffic light cameras), better network efficiency (ramp metering signals etc), improving driver skills, and, of course, “reducing use of motor vehicles”. I’m sure there are a few positive actions we could take on that last point.

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  1. The emissions should improve with time, but there are some caveats. Cars under 20 years old now have to meet Euro IV emissions standards before they can be enter the fleet. Cars over 20 years old do not have to meet these emissions standards, which means things like the early 90s Corollas (which last forever), and the enthusiast Japanese cars (Impreza, Evo, Skyline) are all becoming legal again to import and there are more of them popping up here for sale. While the enthusiast cars might not have much of a drag on the average age, the price-sensitive stuff at the lower end could see a big boost in imports.

    There is a very limited exemption scheme for vehicles under 20 years old that do not conform to standard but they are limited to a couple of hundred a year and they receive far more applications than there are exemptions. It’s pretty much limited to enthusiast cars and they won’t be doing many miles either way.

    1. The emissions standards don’t actually refer to fuel economy/ greenhouse gas emissions – they specify standards for emissions of other undesirables, such as small particulate matter, nitrous and sulfur oxides etc.

      1. Ah, I knew I’d rushed through something there. Still, those particulates are problematic- I suspect we’ll one day look back on our diesel buses with the same fondness that we remember radioactive children’s toys.

  2. Perhaps a variation of Jevon’s Paradox at play there. As we increase efficiency of engines to use less fuel, people’s behaviour changes to take advantage of the fact they can driver heavier cars further using the same amount of energy they previously used. It’s a kind of progress, but not meaningful in terms of evading climate change and peak oil.

  3. I think car manufacturer fuel economy figures are, like cigarette tar levels as reported by the official tests, nothing more than, “works of fiction that both parties willingly want to believe in”.
    With the end consumer being the sucker who believes in them.

    How many modern SUV’s supposedly get well under 10 l/100km, yet in practise few would achieve that.

    I know my Honda Hybrid gets 5.7-6.0 l/100km around town – which is pretty good for stop start driving, when using the AC.

    So yep, those figures are theory at least.

  4. “Reducing use of motor vehicles” is clearly the only thing that will make any real difference. Which we know can be achieved in cities by investing in the alternatives as people then choose to use them as we are seeing so powerfully in Auckland.

    No sign, of course, that the MoT is advising the minister of this. It appears in this paper as an odd little afterthought.

  5. Two factors that may have had a big influence on our VKT figures other than fuel price is the increase in access to the internet (80% of homes had a connection in 2012 compared to 64% in 2006) and the huge increase in public transport use in Auckland (75m trips in November’s 12 months rolling total compared to aprox. 50m trips in December 2005’s 12 month total).

  6. “A lot of people don’t understand the inertia of a fleet with 3.2 million vehicles that tend to get driven for 20-odd years and do 200,000+ kilometres in their lifetime (driverless car advocates take note).”

    For Driverless cars thats a really good point – they will take a very long time to wash through even half the fleet, and most will require extensive ongoing IT system to support them for their lifespans.
    A lot of the current designs for Driverless car rely on the car being able to communicate to the “cloud” for processing and software and map updates with limited onboard smarts for true self-navigation.
    In IT terms, 20 year old IT infrastructure is old, really old, like a hundred years old..So the cars may outlast the systems that make them work.

    Any owners of driverless cars may find after even 5-7 years that they will cease to work properly due to the “back end” infrastructure no longer being there.

    Doesn’t apply to current cars, they are self contained and petrol and other inputs have not changed much in the last 20 years (last big change there was the switch to unleaded fuel in the 90s).

    So driverless cars will be a huge change in more ways than one – it may force people to accept that these are truly disposable cars just like all other products the disposable iPad generation use.

    Another good reason for a private citizens not to own such a vehicle.

    1. GM’s OnStar is a key example of where change, in this case the removal of analogue cell coverage, rendered millions of in car devices useless.

    2. For Driverless cars thats a really good point – they will take a very long time to wash through even half the fleet

      Something that I say every time people try and argue that an SDV nirvana is just around the corner so we should keep on building roads and depriving public transport of funding. My nearly-two-year-old son will probably be on the verge of becoming a grandfather before SDVs are the majority of the NZ vehicle fleet, given both current fleet ageing trends and also the lackadaisical pace at which SDV tech is actually reaching its claimed potential; we still don’t have fully-autonomous cars that are to the point of being able to be built without a steering wheel, and it’s looking like several more years yet.

  7. How will driverless work on rural roads? Will my car drive itself in the Milford Sound tunnel if the mobile reception is non existent? Does the car automatically stop if it loses signal? Do i have to take over control of the car at speed?

    1. A truly autonomous car will be just that: autonomous. The end goal of the tech is a car that does not have a steering wheel (or, at most, has one that folds away in case the operator should feel the need to drive themselves). It will have full GPS, not just cellular-assisted GPS, and a full suite of constantly-updated road maps so that it is aware of road closures and other dynamic changes to the routes.

      The cars Google is trialling can already operate in heavy traffic and at speed. Where they fail at being truly autonomous is their inability to deal with dynamic route changes (road closures, road works, etc) and weather conditions that impair the “vision” of the cameras. They also are limited in their route knowledge to what Google Maps knows, rather than using cartography from roading authorities to build a true GPS-enabled routing system.

      1. “They also are limited in their route knowledge to what Google Maps knows, rather than using cartography from roading authorities to build a true GPS-enabled routing system” – Auckland GIS maps are updated from “as builts” prepared by consultants many months after the road works have been completed. I suspect Google Maps are updated monthly from Council data and so is the best data available.

  8. I seriously doubt driverless cars are going to work. I put it in the same box as Amazons idea to deliver via drone. Imagine in litigation America when a driverless car causes a fatality – you think BP had problems with class action over Deep Water Horizon – Google would be litigated into extinction.
    Emmisions will be reduced through a mixture of hybrids, LNG and synthetic fuel blends – the marine industry (in the real world) is already moving towards this with the bunker spec changes in SECA.
    Cars are here to stay, and as my good friend John – the author of this post – now knows, cheap fuel is going to mean more cars on the road.

    1. Establishing liability for collisions involving SDVs can be handled through legislation, just as it is now. The issue is already on legislators’ radar, because the vehicles are being tested right now. It already required legislation to allow open-road testing, even with humans in position to assume control.

      Even with the ridiculous tort situation in the US cars are still made, people still drive them, and insurance companies still offer cover. Why on earth would SDVs be a sudden exception to this rule?

  9. Numbers of cars on the road relative to fuel used doesn’t seem a reliable measure of efficiency. Could a comparison be made to km’s traveled as available from the registration information so we end up with litres/100km or km/l or mpg say?
    As in the Japanese example. (I assume that is for passenger vahicles? or is it their whole fleet.

    1. Hi Ted, yes the MoT does estimate this in their Vehicle Fleet Statistics, based on WOF odometer readings and aggregate fuel consumption data. We’ve written about those from time to time. The fleet average is about 10L/ 100km for actual on-road consumption in NZ. This has been pretty much flat for the last decade or so (which is as long as they’ve been collecting the data).

      1. Thank you John. So from that it could be assumed that while the fleet is growing in numbers their fuel use has remained constant or are they are travelling greater mileage with the same fuel (since 2006 fuel use is sort of the same)?

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