A few months ago, I looked at the greenhouse gas emissions from cars in New Zealand. As promised, here’s the follow up on public transport emissions.


Sadly, the New Zealand data on public transport emissions is pretty sparse. An OIA request to Auckland Transport only turned up information on Auckland’s train network – and given that we’re going to be completely replacing our diesel trains with electrics by 2016, this information will be out of date pretty soon. The new electric trains will use much less energy (electric motors are much more efficient than diesel engines), and emissions will plummet, especially given New Zealand’s high proportion of renewable electricity. Even the current trains, though, have much lower emissions than cars. In the last 18 months, Auckland’s trains used an average of 1.42 litres of diesel fuel for every 100 “passenger kilometres” they travelled. That means 1.42 litres used to move five people 20 km each, or ten people 10 km each.

From my previous post, New Zealand’s cars use around 10 litres of fuel for every 100 “vehicle kilometres” – that is, for each 100 km travelled by the vehicle. To compare the statistics, you’ve got to know something about the typical number of passengers in a car. Luckily, the Ministry of Transport collects information on this, and it turns out that Auckland cars carry an average of 1.5 people – so one vehicle kilometre becomes 1.5 passenger kilometres.

All up, then, Auckland cars are likely to use about 6.67 litres of fuel per 100 passenger kilometres – and, once you factor in that diesel has slightly higher emissions per litre than petrol, cars create about 4 times the greenhouse gas emissions of Auckland’s diesel trains, per passenger kilometre. Once we switch to electric trains (more energy efficient), using our mainly renewable electricity (much lower emissions per unit of energy), it’ll be a heckuva lot more than that. I haven’t seen any estimates of what the emissions from the new trains will be – surely there are some somewhere? – but it’s probably no exaggeration to say they could fall by 80% or so.


As another comparison, a report authored by MRCagney and featuring our very own Stu Donovan estimates that Christchurch buses get 0.76 passenger kilometres for each megajoule of energy. With a bit of rearranging (energy content of diesel = 36 MJ/ L, and emissions content of diesel = 2.670 kg of CO2-equivalent/ L), I’m calculating that those Christchurch buses use 3.65 litres per 100 passenger kilometres, or 9.8 kg of CO2-equivalent emissions. This is around 36% lower than Auckland’s cars.

Summing Up

So what am I trying to say here? Public transport is good for reducing transport emissions. I’d like to see more New Zealand evidence on this point, and HOP cards will hopefully help with that as it becomes possible to build better estimates of distances travelled. There’s plenty of international evidence, and I’ll tackle that in another post.

In New Zealand, electric trains can do an excellent job of reducing transport emissions, thanks to our wonderful renewable electricity. Buses offer much smaller savings, but, of course, they are much cheaper. There are new technologies coming along for buses, as they are for cars – gas-powered, hybrid, or even electric buses – and those could help to reduce emissions. For the time being, these things are pretty expensive, and it’s hard to know how much this will change in the future (although the costs will come down).

The other thing that makes a big difference is the loading factors. A full bus is going to be much more efficient than a nearly empty one, just like a car. With PT usage generally on the rise, and the redesign of Auckland’s network over the next couple of years, we should be running fuller services a lot of the time (although hopefully not overloaded!)

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  1. Re the visible issue of invisible diesel particles (PM-10) being carcinogenic, while it’s good news that commuter trains running through the city will be electrically powered and PT growth will contribute to reduce overall air pollution, we will see diesel bus numbers increase – which is a problem.

    It is important Council stipulate and enforce that the highest/latest environmental standards are applied to contract operators, idling practices and other mitigation steps taken where there will be concentrations of buses.

      1. Euro 2 standards for buses (ie heavy duty diesel engine) were introduced in 1996. The latest standard is Euro 6 which will come into force at the end of the year. Euro 2 standards aren’t all that stringent; for example, they specify a CO emission of 4g/kWh whereas, since Euro 4 (2005), the specification is for a max of 1.5g/kWh; for particulate matter, Euro 2 allows for 0.25g/kWh whereas Euro 6 specifies 0.01g/kWh. Basically, we’re filthy; I also rather suspect that a significant proportion of the fleet (e.g. the ancient NZ Bus ‘bendy buses’) don’t even meet Euro 2 standards, so we’re even filthier.

        1. Thanks for the info Chris and John. Would be good if AT stipulated Euro 6 or whatever follows for new acquisitions by contractors and that buses operating in CBD /metro areas meet Euro 4 within a defined period. Perhaps a sticker indicating standard on the the back of each bus might help raise awareness and help cull out below standard buses.

        2. A minimum emissions level will have been in effect in vehicle quality standards for contracted bus services for some years, if not decades, Jeff

          standards for contract services tend to set the default for the fleet to avoid issues of allocating buses between commercial and contract trips

    1. Hence my opinion that high frequency lines should be changed to electric asap. North Shore line, Panmure – Botany line. Rail is efficient. The added capital costs are offset in many other ways. Do it once, do it right. I wonder what the efficiency of the Skytrain system is like compared to the EMU’s?

      1. Well I totally support this point.

        Although there are really two issues here, namely grade separation and fuel type. The use of diesel as a fuel raises several issues.. anthropogenic global warming, diesel fume emissions (esp particulates) and fuel dependency. As a cyclist I suppose I harbour a particular hatred for the diesel fumes…

        Anyway, in terms of fuel type, electric buses could deal with the latter point.. and the technology is developing quickly. The latest city to extend a large scale trial is Milton Keynes in England, which is using 8 fully electric buses.. these are quite smart buses too, able to use batteries half the usual size because they are charged briefly at some stops and route end turn-around points by inductive power transfer (IPT).. technology that is developed right here in Auckland.


        Anyone know why we don’t have a similar operation in Auckland?

        1. I do fully support the use of electric buses on local routes and those services do not yet justify the expense of rail.

        2. Anyone know why we don’t have a similar operation in Auckland?

          No unified bus operator, cost, lack of political will at central government level to provide AT the tools to get bus operators to get involved in a trial.

  2. If we (AKL/NZ) were serious about climate change, we’d move to hybrid electric or fully electric buses.

    (We’re not.)

    The emissions profile is massively lower, they’re quieter, they put out less or no noxious gasses (which contribute to the deaths of 400 Aucklanders annually), they have lower maintenance costs, and are a cleaner and smoother ride. We’ve had hybrid buses – for a while they were run on the old inner-Loop. They were turned down because of their higher up-front capital costs.

    1. there were also performance problems when fully loaded on Auckland’s streets, which are hillyer than Chch, it wasn’t uncommon to see them stuck on Victoria St outside Whitcoulls because the batteries had overheated or were undercharged or something

      anyone know where those buses are now? have they gone to Ian Little in Foxton, or Motat or somewhere?

        1. My understanding is that the red city circuit buses were taken out of service because of reliability issues or unavailability of spare parts for the capstone microturbine that was used to power the bus.

          As an engineer the driveline of these buses was very interesting. They had a very small (Diesel fueled) gas turbine (think jet plane or A1 abrams tank), running a generator that charged a bank of batteries which powered an electric motor in full series hybrid style.




    1. Stu will be the person to talk to about this topic, he wrote the report! We should certainly be looking at hybrids and electric buses: no country is better placed to use them than New Zealand. Over the long term they will make a great deal of sense.

      1. Yep, totally agree. But why over the longer term.. why not now? What happened to our kiwi make-it-happen attitude? Why does one of our best local electro-technical capabilities have to be exploited first in Italy, Holland, UK, etc before we use it right here? When did we become so conservative? All why-we-can’t in place of how-we-can?

        1. Because buses last somewhere between twelve and fifteen years in service. Each year we turn over about a twelfth to a fifteenth of the fleet, or in other words not many.

          We’re a small market without the size, diversity or money to be innovators. Our companies can contribute to innovation but it hard for us to run the whole gig. We can however be clever and follow just behind the innovators. Let the large European and Asian markets develop the products and as soon as they have them tested and operating on the market we can buy in.

        2. Auckland’s ancient NZ Bus ‘bendy buses’ were introduced in 1983, so they’ve been on the road for thirty odd years. I can’t imagine that they meet any NZTA emission standard so they’ve probably got an exemption but, hey, we’re a small market and our bus fleet is owned by a bunch of venture capitalists who aim for a 20% return on capital so why should we care about peripheral things like fuel dependency, pollution and climate change, that is if it really exists? Anyway, private cars are far more convenient, so why bother catching a bus?

        3. I suspect (not completely sure) that the old artics (“bendy buses”) are used primarily on school routes that are contracted by the MED. I also am led to believe that the latter organisation has no emissions standards whatsoever, even for school buses that operate in urban areas.

          Hence school routes are run using old diesel belchers.

        4. On the basis of observation, I’d suggest that the ‘bendy buses’ are not entirely restricted to school bus runs; there are at least a couple in Waka Pacific/Go West liveries operating scheduled services at, I suspect, peak times.

        5. Conductix claim payback of around 4 years so the technology is potentially attractive on a 12.5 year life. The European trials all involve fairly moderate costs, few $ m for a small number of vehicles and the power supplies.

          The technology is all fairly robust, been around for 10+ years on buses (Turin) and in Bombardier’s case (and others I think) it’s also used for rail, to avoid overhead lines. The big improvement made in recent years (by the Univ of Auckland team) is getting the power transfer across a larger gap at a sufficiently high efficiency.

          All sounds do-able to me.

          How about the Europeans and Asians build the products.. But we can test them here.. apart from the unique local centre of expertise, AK is a great place to pilot tech innovations generally. In the case of electric bus technology specifically our 75% renewable power is a useful added extra.

          Besides, kiwis were once (and I think still are) innovators. We can be incredibly adaptable, responsive and resourceful if we put our minds to it.

        6. Auckland also has a very broad range of geographical features, which makes it a very good place to test any kind of land-based vehicle (so long as it’s not intended for use in snow 😛 ).

  3. Another context to think of these issues is our over reliance on imported liquid fuels. So along with emissions issues why is there no policy on ‘energy independence’? A phrase most will be familiar with from US reports. While most that is written about US EI is over optimistic nonsense the aim is a good one.

    Here any idea of improving NZ’s EI involves electrifying as much of our energy use as possible. However there is one area where I think there is a important intermediate step. We have a huge sunk investment in FF fuelled road vehicles that we run on imported oil based fuels yet we burn our own Natural Gas to make around 20% of our electricity. To then use this to power vehicles involves additional levels of inefficiency; extraction, generation, transmission, storage (if battery powered), then use.

    So a policy to incentivise the transition to 100% renewable electricity along with a phase in of Natural gas ICE vehicle adaptation, especially for trucks, is a good medium term policy for increased NZ EI.

    Of course continued policies to reduce the need for driving at all is also urgent and vital and completely possible, especially in urban areas. And will result in better, more productive and prosperous cities.

    1. “Energy security”, also known as “energy independence”, a big issue whatever it’s called. New Zealand and other oil importing countries are very vulnerable to any events that might cut off or restrict our oil supply… notwithstanding that our membership of the IEA requires us to have at least a 90 day supply in reserve.

      1. Although due a lack of tanks in NZ we keep a fair chunk of of reserve offshore in places like Japan and the Netherlands,so whether we would actually ever be able to get at our full reserve is a very moot point

        1. Yeah we do keep it offshore, but you’d hope that barring a war with Japan and the Netherlands they would send through what we’ve paid for 🙂

        2. Reliant, of course, on there being fuel oil available to power the ships to bring it to us. And if the world got down to that level, even if .jp and .nl would honour the contracts, it’s highly unlikely that the tankers could make the umpty-thousand-kilometre journey unmolested.

    2. I could be wrong but isn’t Natural Gas power generation a lot more efficient than nearly all internal combustion engines regardless of fuel type? So it’s possible that even with the losses from transmission and storage it could still be more efficient than using the gas directly in vehicles (not that we should be using it at all.)

      1. Generation from combustion generation and then electric traction is almost always more efficient than direct ICE, especially at low speeds and frequent acceleration/deceleration. Plus it is more important to note that it is the first step to renewable electric traction, so even if it were no better than ICE we should still do it.

    1. One thing NZ will have to realise in a couple of decades time; no matter who your friends are, if there is not enough to go around then the big boys will always get theirs first before letting others have a go. It is one of my biggest concerns that it will end in major conflicts between them as well!

      NZ is luck though; we have an alternative that most others do not (renewable electricity) and we need to use it as much and as fast as possible.

  4. Nymex up to USD 108 today. Boy that market is just awash with oil…..

    Not that NZ buys Nymex, but rather Tapis or Dubai, which is usually around 10% higher still.

    This may be a temporary spike but if not, and crude is really testing the USD 100+ barrier, that plus new petrol tax (the RoNS tax, or the ‘Joyce’) and any downward shift in the NZD is going to mean very real pain at the pump for a lot of New Zealanders.

    Already had a 10cent rise in a week.

    Most have bought the complacent nonsense of implied pain free motoring for ever that is this governments rhetoric and actions and will be shocked and not prepared for $3/l petrol.

    There will be political consequences. Stand by for ministers blaming uncontrollable events saying: ‘no one could have predicted such a ‘shock’.

    Tui billboard right there.

    1. Nymex is NOT a crude slate. It is the New York Mercantile EXchange. The Nymex quote you are refering too is the WTI (West Texas Intermediate) which is the bench mark US crude futures contract.
      Most crude oil is bough and sold against the two major bench marks, either WTI or Brent.

    1. It would depend hugely on the specifics of the route, vehicle and loadings. Something tells me our current boats aren’t very clean, but they might still be quite green (when full at least).

        1. Sure, and those are probably the most efficient in every respect. I was more thinking about the large boats of the Fullers fleet tho.

        2. Somewhere in the archives, I have a table which I’ll dig up next time I’m looking. However, my recollection is that passenger ferries do not have flash emissions profile at all. Both full blown passenger ships and quick cats are in this category. May have been equivalent to a Boeing?

          This is one of the paradoxes of marine transport.- class leading low emissions carbon profile for freight, but certainly not the case for passengers. Ships/ferries typically need to lug around a lot of air to carry a payload of passengers which drives down efficiency, unlike a load of logs or containers. I’ll add to this post when I do get a chance to locate that old table.

        3. Most of the Fullers fleet is old by modern diesel propulsion standards. Most emission advances have only happened in the past 10 to 15 years and especially the advent off common rail technology mixed with cat convertors, particle filters and the like.

        4. Your quite right there tuktuk, passenger ferries have the worst per km rate out of any mode and by quite some way.

          They have two things going against them, firstly they have a very large dead weight and base line resistance so the cost of a trip is not notably different from when they are empty to when they are full. The next issue is that the smaller the boat the more resistance it faces per unity weight.

          And I guess one more thing that plays a part. The resistance of water goes up greatly the faster you go, and so if you want a fast ferry you need to be willing to pay a lot more to operate it. Unless of course you try to go with hydro foils.

        5. I think there’s a couple of important distinctions to make with respect to ferries:

          1. Ferries almost always provide a more direct connection than is available via land. Hence the ~3km trip by ferry from Devonport needs to be compared with a ~10km trip by road. This means that in many cases you can’t simply compare fuel/passenger-km rates for land transport modes versus ferries.
          2. Because much of their route traverses water, this reduces the negative impacts on population health that is normally associated with the local emissions generated by ICE. On the other hand, the environmental effects (on the marine environment) may be worse.

          Apologies if these points were made above – I scanned the thread quite quickly.

        6. Stu’s second point is important. Ferries, ships, aircraft and coal fired power stations will individually generate much more pollution than cars or buses, but usually in a way where the problem is disbursed and immediate levels of harm are minimised. There would likely be little real health risks from an old school bus doing it’s back road rounds in country NZ, but it wouldn’t be desirable to fill a highly populated city with hundreds of smokey old buses. I’m not suggesting an excuse, but a hierarchy of priorities be applied when addressing the issues.

          In saying that , if you’re out on the Waitemata you really notice how clean the air is, or was after one of the fast ferries races by.So I think they should set some goals to do better.

        7. As per my post above, here is an archived web link to efficiency figures from a study by a “James Strickland”. http://www.builditsolar.com/References/EfficiencyTransport/strickland.htm
          The original site is long gone, although I have a copy of the information carefully hoarded away as a word document.

          The figures are given as passenger-mpg gasoline equivalents. The eye-catching figures to me are: as discussed, the not particularly flash figures for ferries.

          There are truly dreadful figures for the Queen Mary 2 (17.3), worse then helicopters and a Porsche Carrrera, and only one rung up from Concorde at the bottom of the ladder! A 2100 passenger capacity BC Ferries Spirit Class car ferry (51.7) comes in between a Boeing 737 and a Cessna 172, an 80 seat Griffon 8000TD hovercraft (59.8) comes in between a Honda Gold Wing motorbike and a Bombardier Q300, a smaller 25 seat Griffon 2000TD hovercraft (83.5) is between a 7 seat Ford Explorer in city driving conditions, a 2 seat Smart car in city driving conditions and an Airbus A320. The very best figure for a ferry is a 400 passenger capacity Seabus ferry in service in Vancouver with a passenger-mpg gasoline equivalent of 100.

          Stu Donovan has made a very good point that ferries can provide a far more direct point-to-point journey which will offset their fuel consumption. Stu’s second point on general air pollution can be addressed in two ways. Ferries can do better to minimise some of the downright dangerous particulates being discharged….not sure if they are complying with an Euro emissions standard. On the other hand, the fundamental physical characteristics mean that little can be done to reduce the amount of carbon released – ie the carbon footprint. There are some very clean burning coal-fired power stations these days….but that doesn’t get around their key issue.

          The James Strickland document itself, though now historic (my word archive document dates from 2007), is well worth a read. Vancouver’s trolley buses (688) score spectacularly well in energy efficiency relative to diesel buses (279) and other road-based modes – something for bus advocates in NZ to take note of. I know that Wellington’s trolley buses seem to have their share of detractors…However, it may be that there are a number of local characteristics that could be fixed that are giving the Wellington trolley bus network a reduced performance in a number of areas than say, Vancouver’s network.

          And, no surprises there – at the top of the list are the rail modes topping out at 2520 for a crush loaded subway, and 2040 to 2460 for a Siemens Combino tram. I think definitely room for interpretation based on how crush-loaded rail modes are, plus off-peak running etc….but gives a pretty strong fuel usage and emissions argument to support rail investment, so long as patronage is in line with capacity provided.

  5. Should be talking about PM2.5 as well as PM10.
    NZ’s diesel fleet and archaic open fires are filthy.

    1. I think the emissions focus of urban transport (and other urban things) should be to improve air quality rather than to minimise CO2 output. Fine particulates and harmful exhaust gases such as CO, NOx and SOx kill many New Zealanders each year.

      I acknowledge that CO2 is important from a climate change perspective but think that urban air quality is the bigger issue for auckland right now.

      1. Air quality’s important, but there have been massive improvements in vehicle cleanliness in the last few decades, helped by more stringent regulations, and that will continue. The main problem is that most of our vehicles are pretty damn old. It will improve as we replace our vehicles, but it’s a slow process.

        1. Regulation is the key driver of emissions improvement. Thankfully California does this for most of the world to follow. We have a poor record in this regard, and we don’t even have a vehicle manufactoring industry to placate.

  6. Nice post! We can also add on the 17 tons of Carbon emissions in the manufacture of an medium size car, which has a much shorter working life that a PT vehicle.

    1. My car works fine after 20 years of service (when it is registered), I wouldn’t want to be on a 20 year old bus, maybe a 20 year old train.

      1. Sorry, I should have said “will have a much lower number of passenger kilometres in it’s working life to apportion that pollution across than a PT vehicle “

      2. If you had a 20 year old bus that had done the same mileage as your car it would probably be in fantastic shape, especially if they had kept up with the maintenance and refurbishment program.

  7. There is some very interesting information coming out here. I am very impressed with the fuel consumption we are getting from the diesel trains. It makes you wonder why we are charged so much to run them. It would be interesting to have a comparision between the DMU’s and the SA sets. I have heard the DC’s are real guzzlers. Still they are on the way out although any future expansion of Aucklands suburban rail network would still require a deisel fleet.
    The other mode we have not discussed so far is trams or light rail presumably they would be even more efficient than electric buses because of less rolling resistance of steel wheels on steel rail compared to rubber on tarmac.
    The other aspect is to consider installing renewable electric power generation in the Auckland region to specifically power our fleet. Solar PV, wind. The council is already involved in land fill and sewage generated methane. Would there be any opportunity to install micro hydro in conjunction with the regions water works.

    1. They have high staffing requirements. At the barest minimum it’s driver plus one, and peak services it’s driver plus two or three. Even with the arrival of HOP it’s still not possible to have driver-alone, as I understand it, due to the driver’s lack of visibility and control over the doors. Plus, they’re old, and expensive to maintain.

      Also, a loaded peak-hour service has done several hundred passenger kilometres by the time it reaches the next station. So although the efficiency is very high it’s still a whole hell of a lot of diesel, and that incredible efficiency in the peak is offset by the low efficiency in the off-peak because it takes a lot of kilometres to get 100 passenger kilometres but the train must still drag around its base weight. I suspect that the median efficiency of the trains will look rather worse than the mean, precisely because the peak services are clocking up thousands of passenger kilometres with every journey.

      1. Well unless John’s figures are wrong rail uses less than half as much diesel as a bus and as well needs less staff than a bus to operate. Probably Auckland trains are helping to prop up Kiwirail. But anyway that’s getting off topic.

    2. The best thing for producing a shift to distributed generation is for government to simply to alter the relationship between the customers and corporate suppliers of electricity to incentivise local generation.

      Feed in Tariffs.

      This is the main tool that has radically altered Germany’s generation profile, enabling a move away from Nuclear and eventually coal there. And also radically lowering the cost of electricity.

      It is now happening in Australia to dramatic effect; check this out: http://theconversation.com/summer-on-the-nem-12635

      and has just been increased in Japan as the last act of a departing PM to a level that analysts are seeing as transformative: http://tcktcktck.org/2013/06/japan-on-track-to-be-worlds-largest-solar-market/53470

      The world is at the beginning of a huge Energy Transition and despite our head start, or because of it? and backward looking politicians; all that hydro, huge natural advantages; we’re windy, sunny, and have hot subterranean rocks [Geothermal] we are lagging behind, but could so catch up.

      The issue of what’s best for consumers, the environment, and our energy security, and balance of payments v what’s best for corporates is a complicating issue….

        1. You have to put things in perspective. Germany started from less than 5% renewables share whereas NZ has nearly 80% right now.

        2. How does “putting things in perspective” change the veracity of the original statement?
          The German PV subsidy programme effectively paid my salary for more than a decade and it has resulted in many benefits…but cheaper electricity is not one of them

        3. Sure, building ANY new generation will cost more in the short term to using existing infrastructure. Germany’s investments will pay off over the longer term however, and depending on FF input costs that may be sooner rather than later:


          But also the low to ‘free’ marginal cost of renewable output is very disruptive to the producer/consumer relationship shifting the capture of this saving to the consumer. Terrifying for corporates in this sector. And can and does lead to savings for consumers even in the context of higher cost in overall generation mix: low to negative power prices in markets flooded by periods of renewable over supply.

          The UK is in a terrible place in terms of energy supply. The market signals of its structure fail to provide long term solutions. North Sea oil and gas was like a drug they couldn’t see past and is now well in decline (production down over a half from 1999). Crappy old nuclear that needs who knows how many billions just to make safe-ish and decommission. Forces like the Telegraph fitting the great evil of wind turbines… No apparent ways to stimulate small scale local gen like in Germany but rather desperate continued clutching at same old solutions: corporate, FF, largescale centralised generation, the latest longshot involve fantasies of replicating the US fracking solution in the Midlands.

          They need to get transitioning to renewables fast and slow down both the use of their own production and reliance on imports. Have they got the structures and processes to do this? Or the political will?

        4. “But also the low to ‘free’ marginal cost of renewable output is very disruptive to the producer/consumer relationship”
          The marginal cost of PV at midnight is effectively infinite. The marginal cost of wind-generated electricity when there is negligible wind is effectively infinite.The consumer expects continuous availability of electricity. If you were to free electricity utilities from the requirement to match supply with demand and ignore capital costs and tolerate large variations in supply voltage and frequency you could have very low cost electricity…but in the real world that is not a practical proposition. Time to take off the rose-tinted glasses.

          The German government is aware that they have gone as far as they should with feed-in tariffs and has begun to incentivise storage and scale back the FITs.

        5. MFD, from what I’ve read, It’s not the electricity that’s expensive in Germany but the cost to get it around the country. The old lines set up was based around a few generation plants and now they need to create a web, so to speak, in order to distribute it. I’m guessing New Zealand could be in a similar situation if head down the small solar / wind route. I think it is the right thing to do but we need to allow for costs to distribute. On the other hand, decommissioning nuclear plants is apparently very expensive and always gets left out of pricing discussions.

        6. “It’s not the electricity that’s expensive in Germany but the cost to get it around the country”

          And that is a direct corollary of the types of renewables that Germany is using. They lack dispatchability and hence there are times when large amounts of conventionally-generated electricity need to be transported long distances to make up shortfalls in renewable generation. It is primarily a technical issue to be addressed . It is not a vast commercial conspiracy as some overimaginative binary thinkers maintain.

          Denmark generates a high proportion of its electricity from wind. It also has one of the highest electricity prices in Europe, if not the highest. There are times when Denmark sells wind-generated electricity to Norway at a low price. There are other times when Denmark buys electricity from Norway for a high price. Why the difference in transfer price? Norway’s electricity is available on demand. Denmark’s is not. Why the high consumer price for electricity in Denmark? Because maintaining a grid with close to 100% availability and tight voltage and frequency windows using wind-generated electricity is expensive (as is PV).

        7. A discussion of price and investment in electricity in Europe. Containing these two quotes:

          With so much energy coming from renewables, many fossil fuel plants can no longer compete on price. Despite the upfront costs associated with green energy projects, they are inexpensive to run. In contrast, Europe’s gas and coal plants, which also provide backup power when renewables cannot operate, need constant spending on fossil fuels.


          The rising output and falling prices of green energy may be part of the problem for fossil fuel generators, but they are part of the solution for energy consumers.

          It is a chaotic situation because there is an energy source transition underway.


  8. A recent Masters thesis was done on Auckland Urban bus fleet and emissions.
    By each Euro standard the number of buses, the total kilometres (in millions per year) and the average (in 1,000km) were
    Euro Buses M km Ave km
    0 134 5 37
    1 132 5 38
    2 88 4 45
    3 315 21 67
    4 121 9 74
    5 207 8 58
    Total 997 55 55

    30 of the Euro 0 standard were articulated buses (bendie buses) and all were registered before 1991.
    The Euro 5 are put on the inner city buses which travel at 9km/hr so the average is low.

    1. Can you send the link please? I’d be keen to have a read and update this post to put the emissions stats in.

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