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Transport Capacity

This infographic from the Asian Development Bank shows excellently why cars are the absolute worst mode for moving people around if you want to have a dense city centre. In Auckland we still devote the majority of the street space we have to them and very little to anything else.

32 comments to Transport Capacity

  • Brendan

    According to https://www.eta.co.uk/2011/12/13/co2-emissions-from-cycling-revealed/, cycling is responsible for CO2 emissions of 21g per km, or 43,199km for 1 Ton of CO2, so two people in a car produces less CO2 than two people riding bikes.

    • Steve D

      Maybe they do and maybe they don’t, but the study you linked doesn’t support that. It says a car produces 271g per km, more than 12 times greater than cycling.

    • Ash

      CO2 emissions from cyclists are somewhat contingent on what the cyclists are eating. Michael Pollen argued that vegans driving Hummers were responsible for a smaller quantity of CO2 emissions than meat-eaters riding bicycles. That was probably a fairly gross exaggerration, but nonetheless what cyclists eat for fuel makes up the largest part of cycling emissions.

      See for example: http://www.guardian.co.uk/environment/2010/jun/08/carbon-footprint-cycling

    • Bbc

      If you also ignore that the car drivers are also eating food and probably just getting fat and if you ignore the CO2 used to produce a car or a bike and if you ignore all the pollution from burning petrol and if you ignore all the road space being built for the car then yes I am sure you can come to the conclusion that cars are more environmentally friendly than a bike. Having spent my life in research I know that if I make enough assumptions I can come to whatever conclusion I want.

    • Ah, Brendan, you need to read the report you have linked to. It paints a far different picture to what you think it does. Page 14 of the report will give you what you need. The fine print also shows the figures for cars do not include cold starts or running with A/C on which of course will make the figure worse again.

    • Max

      This argument that 2 cyclists give off more C02 than 2 people in a car is laughable on the face of it, on a “don’t even need to think about it” level. I started giving an explanation why, then just decided that it was too likely to be trolling and/or waste of my time.

  • Those figures are quite subjective, in terms of metro rail, and trolly buses (if electric buses thrown into the mix), it depends on where the power source originates from. Could be worse or better than above.

    • I agree the figures are subjective. Considering that humans have a tendancy to breathe anyway no matter how they are transporting themselves, it would be more accurate to say walking and bicycling put negligible *additional* CO2 into the atmosphere. And, yes, not sure what assumptions they have made about the propulsion of the metrorail either.

      • Ash

        Cameron, the amount of carbon produced in fueling each mode of transport is the relevant factor. Generally, cyclists and walkers burn more calories than somebody, say, sleeping or sitting in a chair, so it comes down to the CO2 embodied in the food they’ve eaten to replace the calories burnt, along with some amount of lifecycle emissions for manufacture and transport of the bicycles themselves, along with infrastructure provided for cyclists.

        • Bbc

          But the car drivers probably eat no less and instead go to the gym and waste that energy so including the food in the calculation is pretty meaningless.

          • If we are going to get picky about the pedestrian / car driver carbon then we’d better remember to factor in the entire existence of the bus driver. And worse for trains the driver plus ‘revenue protection officers’

          • Ash

            Karl, how that equation pans out depends a lot on passenger loadings, I think. Auckland’s new electric trains will carry a maximum of 900 passengers per driver, probably with a train manager and several RPOs, as you call them. Perhaps 4 or 5 people for a load of up to 900.

            Contrast this with the bus which carries 30-50 passengers per driver. To transport those same 900 people in buses might require as many as 30 drivers.

      • Peter M

        That’s a somewhat bizarre outcome. So we should all be slobs and not burn calories?

        • Completely absurd argument; the human in each case, unless we kill them [and even then the body rots releasing carbon] will consume and excrete carbon whether or not they drive a bus or a train. Being a bus driver does not in itself do anything to the global carbon balance. Also, in the case of the cyclist who may eat more because of the energy needed to ride, just leaving that food uneaten and rotting it will still release its carbon. Net sum zero. Sure we could all die and not farm and eat and that would help but living is to take part in the natural carbon cycle. A tree is a carbon store until it rots or burns; so a timber building is a carbon sink while it stands, but still these are really issues around the timing of the return of the carbon to the system rather than game changing alterations to the net carbon balance.

          In complete contrast to fossil fuels pulled out of the ground and burnt, these add formerly absent carbon to the biosphere.

          So it makes enormous difference if a vehicle is fuelled by renewable electricity of one time only fossil fuels. the chart above should be clearer about electricity source.

          • Ash

            I doubt anybody seriously questions the CO2 emissions of a person or the food they eat if they’re travelling by bicycle or walking. And in the case of motorised transport, the emissions of the people (drivers/staff and passengers) are negligible given the scale of emissions from the motive power etc.

            I think this has been an exercise in humouring the people (often transit/active transport detractors) who try to make outlandish arguments such as that a cyclist who eats a lot of meat is worse than a vegan in a Hummer.

  • Are the units wrong in the infographic, or is it just facile?
    I don’t see how cars are only delivering 2 people per hour (and equally buses only 9 etc)

    • Glen K

      The source is German; Europeans use a comma for a decimal place and vice versa. So it’s 2000 people/hour, which is about right given typical peak car occupancy.

  • Nick R

    2,000 people per hour by car in mixed traffic is pretty damned high, they must be assuming maximum occupancy of each vehicle.

    • Steve D

      2000 people is about right for a single motorway lane – that’s 1800 cars travelling 2 seconds apart.

      • True but that’s a fairly academic comparison, if you’re talking motorways then it’s not really a “3.5 meter lane in the city”, it’s more like 6m (a quarter of a 24m motorway corridor).

      • Peter M

        Your typical road with regular intersections carries about 600 vehicles an hour.

      • Steve D

        A motorway is the equivalent to BRT lanes and railway lines, which are also going to be grade separated with two or four lanes/tracks. That double busway (two lanes each way) is going to be a similar size and shape to a motorway.

        Another thought is that they might be counting “mixed traffic” as being a typical road with intersections, with mostly cars but a few buses mixed in.

  • TheBigWheel

    The CO2 chart states “all values reflect a 100% occupation rate”. It’s not clear whether that also applies to the road space chart? The bus to car ratio seems on the low side to me.. during the debate about the Remuera Road bus lanes I read that during morning peak traffic, 45% of people travelling towards Newmarket occupy 2% of the vehicles.
    On the other hand whilst I agree with Brendan that the CO2 chart understates the CO2 requirements of cyclists (we eat more than drivers!) it also massively understates CO2 emissions from cars. With a more typical single occupant per car, the chart should surely show cars off to the right at 7,000 km. Plus, the carbon content of a car is far more significant than a bike.. at about 17 tonnes apparently: http://www.guardian.co.uk/environment/green-living-blog/2010/sep/23/carbon-footprint-new-car Which is a decent proportion of the lifetime emissions from driving it. Move the car even further off the scale….
    The energy consumption chart isn’t clear to me: how does the “transport” increase break down? More travelling (more air travel)? More energy intensive travelling (cars instead of buses or trains.. or bikes)? More food miles?

  • Interesting that bus is less polluting than rail. Often operates at higher load factors too.

    • Pim

      I think they’re assuming that the buses run on Diesel, and the trains run on Electricity.

      • Luke C

        I think they’re assuming trains run on electricity that is mostly from coal fired stations. You could probably argue forever if this will be true in Auckland or not though!
        Makes a big difference if you have local air quality issues, especially if exaggerated by terrain. For example diesel buses pollute local area, but coal fired electric trains often pollute an area further away and can be scrubbed of particulates.

  • PBY

    Why does the info graphic show a 2 lane BRT, when all the other comparisons are single lane or 3.5m corridor? I like the message the info graphic sends but it’s a little inaccurate/misleading.

    • Max

      Yeah, I thought that was a bit forced. A heavy rail also can’t fit into a 3.5m lane either (physically, it may be, but not in practical design & operation) – it would have been better to simply say a “one vehicle abreast” or something.

      • Perhaps better would have been a comparison of what can fit into:
        – one 3.5m traffic lane (i.e. general surface traffic, bus lane, ;street’ light rail lane, pedestrians, cyclists)
        – one 12m corridor (BRT busway, light rail RT, heavy rail)
        – one 25m corridor (four lane BRT busway, motorway, mega rail line)

  • Peter M

    I’m not sure whether Mumbai’s “hyper dense crush load” is something we ought to aspire to, but an interesting diagram for sure.

    I think the two-lane each way busway is intended to highlight that even that is below the capacity of metro rail.

  • Did anyone notice this: ‘All values reflect a 100% occupation rate’ in the fine print? So, the figure for the car is with 4 or 5 people? With 1 person that figure would change the passenger km dramatically and show the car is a far worse light if I’m correct.

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