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Transportation United Kingdom

London's Deputy Mayor On Ditching Diesel 188

dkatana writes: During an interview in Barcelona last week, at the Smart Cities Congress, London's Deputy Mayor Matthew Pencharz said that he doesn't believe diesel cars belong in cities. He said, "I don't believe that for the urban setting, for light vehicles, diesel is the right thing," He added, "I don't think it is the right thing if you are an urban driver, stopping-starting in traffic all day, not going very far, not zipping along at 50 mph on the motorway. [I think] diesel is not the right technology." He also blamed the European Commission for being too lenient with emission standards and conformity factors. "The conformity factors the Commission [has recently approved] are not as good as we would like, clearly, because we are going to have the same problem again," he said. "The VW scandal has focused attention on a problem we hardly knew about, and it has raised to the top the public policy of failure of dieselization across the European Union, and the UK too, combined with the spectacular failure of the Euro engine standards," he said. "[The scandal] has focused our minds on the fact that we need to accelerate the way out of diesel."
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London's Deputy Mayor On Ditching Diesel

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  • by skids ( 119237 ) on Friday November 27, 2015 @03:12AM (#51011741) Homepage

    urban driver, stopping-starting in traffic all day, not going very far

    Kinda the sweet spot for hybrid-electric drives, no?

    • by invictusvoyd ( 3546069 ) on Friday November 27, 2015 @03:31AM (#51011789)
      I think this is the sweet spot for a highly optimized public transport system .
      • by luvirini ( 753157 ) on Friday November 27, 2015 @04:14AM (#51011945)

        Indeed, city centers are specific places where cars and similar vehicles have very little reason to be in if your public transportation works well. Note that that requirement does include the need for easy access "park and ride" for switching between public transit and cars.

        • by gibbsjoh ( 186795 ) on Friday November 27, 2015 @07:46AM (#51012453)

          Works well and is cost-effective. If my other half and I go into London from where we live in the suburbs, it's invariably cheaper to drive and pay out the nose for parking than it is to get the train. Not a few pence cheaper - around double the cost. And we're not far from London at all; we're in the commuter belt.

          • by Bert64 ( 520050 )

            That's what people often fail to consider, the car costs about the same for between 1 and 5 people, or more if you have a 7 seater etc whereas the train ticket costs increase linearly.

            Carrying goods is impractical on public transport too, so going on a shopping trip is painful without a car.

            • by Rei ( 128717 )

              And even the best public transport system generally isnt going to start and stop *exactly* where you need it, so there still is going to be *some* walking. Which some people with disabilities or health problems simply can't manage. And to achieve a good public transport system - with frequent stops, densely placed stops, relatively direct routes and affordable prices - is entirely dependent on population density far more than it is on "will". In places with high density, it's a relatively straightforward

        • Or even better, design good high density living within walking/cycling distance of Metro stations so that people don't need cars at all.
          Having been raised in a place with crap public transport, then having the opportunity to live in Hong Kong for a couple of years and never once not needing a car, I feel this is the only model that really works in a large city.
      • by tomknight ( 190939 ) on Friday November 27, 2015 @10:37AM (#51012975) Journal

        But too many people forget a large number of journeys need to be made by vans - workmen with tools, deliveries and so on. All something public transport can't really help much with.

      • Aren't most public transport buses diesel powered? I know the ones in Baltimore are Natural Gas powered, but not all cities have ready access to methane like we do in Baltimore.

    • by Mashiki ( 184564 )

      Kinda the sweet spot for hybrid-electric drives, no?

      Well trains aren't hybrid electric, but they're diesel driven electric. A few companies like Freightliner and Mack have been messing around with it for a few years, but there's problems mainly to do with the raw torque requirements for trucks, especially on heavy grade pulls. One of the solutions(can't remember if it was Mack or Freightliner), went with both. Diesel-electric for long cruising and diesel drive only for startup pulling and grades.

      • Never heard of a hybrid train. Diesel-electric usually means diesel engine with electric transmission.

        • They're toying with the idea in Britain - overhead electric with a diesel generator for non-electrified stretches. Probably not what people have in mind when they consider hybrid but it does fit the definition.
          • by Alioth ( 221270 )

            It's been done in Britain before. The Gatwick Express used to be hauled by electrodiesel locomotives for a good couple of decades.

        • Hybrid trains are around now. Trains always used to direct electricity generated from braking to big load banks on the roof of the locomotive. In 2007 GE rolled out the first hybrid train that stores the braking energy in a battery bank instead of just dumping it to a giant heater.
        • In the US, where the rail lines don't have electric, the trains are diesel electric serial hybrids. The diesel engine directly runs a generator, which provides power to an electric motor. They have electric braking too, but the power is dumped into a resistor bank, not reused.

      • Kinda the sweet spot for hybrid-electric drives, no?

        Well trains aren't hybrid electric, but they're diesel driven electric.

        Uhm... normally, they're purely electric [wikipedia.org]

        • These are diesel-electric [wikipedia.org]. So are these [wikipedia.org]. And a lot of freight engines throughout the world are as well.
        • by Z00L00K ( 682162 )

          Depends on where in the world you are, but diesel locomotives usually have a generator that produces electricity to electric motors for traction. It allows for a smoother transition of power since the electric converters acts as a gearbox. In western Europe most trains are electric but on some tracks there's no overhead lines and then the diesel-electric locomotives are used.

          A hybrid is essentially just having both overhead lines and diesel engine/generators to feed the traction engines.

          However when it come

      • In London and it's commuter belt, trains (including the Underground) are powered by an electrified third rail. No diesel required.
        Most (but not all) inter-city lines are powered by overhead wires.
        • by xaxa ( 988988 )

          Almost right, but the third rail system is mostly south of the river. North of the Thames you will find overhead electric on almost all routes (including commuter routes, London Overground etc).

      • So your argument is rubbish. ALL modern locomotives have electric traction motors whether powered by an onboard diesel engine or from overhead wires. Ok, in some cases thats due to it being simpler and more reliable than having a mechanical drivetrain from the engine to the wheels, but the point is those electric motors can start an X thousand ton train so they won't have much problem with a 30 ton truck.

    • by AK Marc ( 707885 )
      Then Diesel loses all its advantages. Diesel is only a good engine choice if you want a Diesel generator on board for a pure-electric car. If you want good peak power to give mechanical boost to electric (as every hybrid in the market does), then you want gasoline, with better efficiency in a hybrid configuration of that type. Also note, that VW is talking about a Diesel hybrid, but there are none in market. Because they suck. Toss a generator in the trunk and use that to charge the car while driving i
      • by Anonymous Coward

        This is probably the least informed comment I've seen on Slashdot for a while: Diesel hybrids are on the market today, from e.g. Volvo and Citroen.

        There is a single reason why Diesel-electric hydrids are rare today: Cost. Modern Diesel engines are significantly more expensive than gasoline. Combine that with an electric drive, and you have a really expensive system.
        But apart from that, a Diesel-electric hybrid is the best technological solution: The electric drive can make sure the Diesel engine is at a goo

        • by AK Marc ( 707885 )
          None of those available in the US. At least not according to the most recent articles I found.

          Diesel is better at a single speed, like you say, charging for a long, steady trip without much stop and go. But read the topic. Cars in London. There's lots of stop and go in London. The smaller gasoline hybrids dominate in that space.
    • Nope. The sweet spot for bicycles.
      • Re: Imbicycles (Score:3, Interesting)

        In London, bicycles effectively use about 2MPG of diesel by slowing large numbers of buses and trucks to the position where they are unable to get out of low gear. They are one of the biggest causes of pollution from diesel.

        If you got the damn bikes of the road, the diesel vehicles would pollute far less.

        And, as for public transport - sure, take your desktop computer, server or laser printer (or even your weekly supermarket shopping) under your arm on London transport in the rush hour. You can post the

        • Re: Imbicycles (Score:5, Insightful)

          by Christian Smith ( 3497 ) on Friday November 27, 2015 @09:49AM (#51012769) Homepage

          In London, bicycles effectively use about 2MPG of diesel by slowing large numbers of buses and trucks to the position where they are unable to get out of low gear. They are one of the biggest causes of pollution from diesel.

          If you got the damn bikes of the road, the diesel vehicles would pollute far less.

          Yeah. Damn those bikes. We'll ignore the effect of the pedestrians, lights, junctions, general congestion and all the other factors that contribute to stop/start traffic.

          And, as for public transport - sure, take your desktop computer, server or laser printer (or even your weekly supermarket shopping) under your arm on London transport in the rush hour. You can post the video on Youtube afterwards.

          You know, the number of times I've taken my desktop computer to work, along with my weekly shopping, makes me glad my town barely has public transport. It would be a daily grind for me to lug all that around.

          And I can testify that most of the single occupancy cars blocking the roads have a similarly burdensome commuter load.

        • Well, you decided it was a good idea to treat Bikers as non pedestrians ages ago, before standard bike frames was even introduced.
          Now you have to live with that.
          It didn't have to be like that at all.

        • by hey! ( 33014 )

          ... assuming that if the bicycles weren't there that their riders would just disappear, rather than switch to cars.

    • Too expensive.
    • by AmiMoJo ( 196126 )

      Petrol-electric hybrids would be better. Diesel is just dirty, even if the MPG is a bit better. Or just go fully electric. When you look at the number of expensive BMWs, Mercs, Audis, Land Rover tractors and the like in London it's obvious that they could afford a Tesla too. For businesses operating within London a Leaf or eNV-200 van would be fine.

      There are taxi companies that use Leafs. Very cheap to run, range is no problem as they have their own rapid chargers that only take 30 minutes to add 80 miles.

    • Kinda the sweet spot for hybrid-electric drives, no?

      It is, but not with diesels, because they don't start-stop as gracefully as gassers, and probably never will — at least, not until gasoline engines eliminate their startup advantage by becoming just as high-compression as diesels. And in fact, the trend we are seeing in gasoline engines is to move towards higher-compression direct-injected designs, or to moderate-compression DI engines with turbochargers. In the bargain they are becoming just as expensive as diesel engines, because now just like the d

    • Hybrid electrics complement gasoline (petrol) better than diesel. You basically have three modes of vehicle operation you want to optimize. Acceleration from a start, highway cruise (only requires about 20-25 HP for most cars), and acceleration at speed for passing on the highway.

      Gasoline engines hit their torque peak at mid-RPM (torque is basically how much energy is generated per cylinder firing), and their power peak at high RPM (horsepower is how much energy is generated per second, so torque * RPM
  • IIRC diesel engines are extremely efficient when idle. So much so, that unlike with gas engines, it doesn't make sense to shut them down if they are going to be idling for a few minutes.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      Diesel engines take shitton of time to warm up because they are efficient. And during the warm up they emit shitton of PM. Then the efficiency of an engine doesn't mean it is clean. While it's true for CO2 it is NOT for NOx. It's actually a trade off: either you're efficient and have low mpg but produce lots of NOx, or you run LESS efficient but produce less NOx and more CO2. Gasoline engine doesn't have this problem because they're not running at an over lean mixture (lambda>>1).

      • Modern diesel engines take a surprisingly short amount of time to warm up. Remember that in order to keep up in efficiency with diesel petrol [gasoline] engines have a lot of the same problems as diesel, and they're running hotter in order to burn the fuel more throughly. More thorough fuel burning, more emissions and modern petrol engines are outputting a lot more NOx than anyone is saying.

        Basically, petrol car manufacturers are getting desperate as the oil price continues to fall. How VW gave them this
  • Hating on Diesel (Score:4, Interesting)

    by segedunum ( 883035 ) on Friday November 27, 2015 @05:35AM (#51012147)
    Ahhhh, desperately trying to denigrate diesel in favour of petrol in the face of a rapidly falling oil price. Good luck with that.
    • by Viol8 ( 599362 ) on Friday November 27, 2015 @06:02AM (#51012203) Homepage

      In the UK anyway.

      And diesel IS a filthy fuel. Even most new cars don't meet the limits set outside the test lab and once the car is 2nd or 3rd hand and isn't being maintained properly or if its a van thats been thrashed all its life it'll start belching black shit out of its exhaust on acceleration (which is barely tested in the MOT). I see these vehicles every day on the road.

      • Re: (Score:2, Informative)

        by drinkypoo ( 153816 )

        Gassers put out just as much soot as diesels [acs.org], but it's the more dangerous kind of soot that you can't see. The fuel is also more volatile and all gassers spit unburned fuel until they enter closed-loop mode. They do that a lot faster these days, but it's still true. Diesels always run lean, they don't have that problem. They have the problem that since they run lean, they produce more NOx. You're upset because you can see the soot, but breathing gasoline does more damage to your lungs.

        • by Viol8 ( 599362 )

          "it's the more dangerous kind of soot that you can't see"

          Diesels also release invisible soot - PM 2.5, far more so than petrol engines.

          "but breathing gasoline does more damage to your lungs."

          Maybe so, but the total released by a petrol driven car will be far less than the soot and NO2 released by a diesel going the same distance.

          • Diesels also release invisible soot - PM 2.5, far more so than petrol engines.

            Hey, here's an idea, why don't you try reading the link I posted which points out that this isn't actually true because the soot that gassers produce is so fine we could not even measure it until recently? That will help you waste less time making erroneous statements.

            • No matter how many times you post it it won't make it true. In your link, they don't even test petrol cars for soot, just assume that the discrepancy in their models is due to them. Hardly overwhelming evidence.

              • I'm afraid it does. There is an awful lot of NOx and soot that has appeared from somewhere, and the uncomfortable truth is that it isn't all down to diesel vehicles. Modern petrol/gasoline engines have essentially had to run hotter and become more like diesels to keep up with efficiency. More thorough burning of the fuel means more emissions.

                People and the industry desperately trying to big up gasoline/petrol are backing the horse and cart. Its days are over. The emissions card is all there is left to pl
                • I'm afraid it does. There is an awful lot of NOx and soot that has appeared from somewhere, and the uncomfortable truth is that it isn't all down to diesel vehicles.

                  I'm more familiar with pollution in cities in Europe, but we've got a good idea of where the NOx comes from, as it can be measured easily from different vehicles. And those measurements show that diesels don't perform nearly as well on the road as they do in the lab (not just VW ones either), whereas the petrol ones do much better http://www.theicct.org/blogs/staff/laboratory-versus-real-world-discrepancies-nox-emissions-eu

                  Modern petrol/gasoline engines have essentially had to run hotter and become more like diesels to keep up with efficiency. More thorough burning of the fuel means more emissions.

                  The measurements show the opposite, with NOx for petrol engines going down and down.

                  • I'm more familiar with pollution in cities in Europe, but we've got a good idea of where the NOx comes from, as it can be measured easily from different vehicles. And those measurements show that diesels don't perform nearly as well on the road as they do in the lab (not just VW ones either), whereas the petrol ones do much better http://www.theicct.org/blogs/s... [theicct.org]

                    Yes, it's been so easy to measure that it took years for anyone to realise what VW were doing. In fact, in London most of it comes from about 400,000 exempt large diesel vehicles like buses and trucks so that's one easy win. However, we're not going to suddenly run those on petrol because it's uneconomic and would produce far more emissions by burning through more petrol per volume. Like diesels, petrols aren't nearly as 'clean' as anyone would like them to be, not to mention being less efficient. They are

                    • Yes, it's been so easy to measure that it took years for anyone to realise what VW were doing... I'm afraid after VW none of these studies are really credible in any way.

                      People realised the basic problem for ages, they just thought it was due to the tests being unrepresentative of real-world driving - which they are, and is the correct explanation for most car manufacturers as far as we know. The studies are as valid as they ever were in terms of the effects they describe, which is that NOx from diesels in the real world is higher than the official test figures say.

                      Like diesels, petrols aren't nearly as 'clean' as anyone would like them to be,

                      No, but they're cleaner than diesel, and they're the most readily available alternative for cars. Heavy vehicl

        • Did you read that article? They find more carbon than they expect so surmise it must be the fault of petrol vehicles? I'm not sure we can rely on that at all as a definitive source.
      • van thats been thrashed all its life it'll start belching black shit out of its exhaust on acceleration (which is barely tested in the MOT)

        I always assumed white van man considered this a feature, not a bug and paid their dodgy mate to tune it up to be just-so when it comes to belching black smoke. It's like the thick yet incredibly uniform layer of grime which is so good for writing witty slogans on. I have a working theory that it's actually impossible to curate that by natural means and there's a small

      • Petrol is heavily, heavily subsidised in the UK. It is simply a more expensive fuel to refine and more of it needs to be transported when compared with diesel. More petrol gets used, hence more of it is transported. Simple.

        There are many explanations for petrol being less expensive than diesel on the UK. None add up. As the oil price falls that puts ever greater pressure on the fuel that is most costly to produce. No surprise that in the UK a lot of disdain has been thrown diesel's way, along with the no
    • The relative price differences between diesel and gasoline vary by country based on which one and how much they tax.

  • by MtViewGuy ( 197597 ) on Friday November 27, 2015 @12:14PM (#51013513)

    The problem with diesel engines is that to make them just as clean as gasoline engines, they require a combination of diesel particulate filters and a selective catalytic reduction (SCR) system to make it easier to remove NOx gases--the combination of the two is NOT cheap, as anyone notes from a US-legal Mercedes-Benz or BMW turbodiesel car. And how well will those systems stand up to the type of demanding usage on a taxicab with its heavy stop and go driving.

    I wonder why London Mayor Boris Johnson didn't announce a plan as far back as 2010 to phase out the use of diesel engines on London taxicabs and buses in favor of using compressed natural gas (CNG). Here in the USA, many cities are now mandating buses and taxicabs switch to CNG, and in Asia, CNG have been used for buses and taxicabs for many years.

  • The VW scandal has focused attention on a problem we hardly knew about,

    Because, prior to the VW news breaking, nobody was looking for some source of excessive NOx emissions that couldn't be accounted for.

  • Perhaps the EU has trouble moving because there is a very strong diesel lobby in France. The rare cases where french politicians raise their voices at EU level seems to be when french lobbies pressure them.

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