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  1.  
    http://nordic.businessinsider.com/i-talked-to-finlands-only-self-made-energy-billionaire---and-now-i-realize-how-utterly-futile-electric-vehicles-are-in-addressing-climate-change-2017-2/

    Interesting article in the above link which lays out one man's view as to why electric vehicles will not solve the problem of carbon emissions as the increasing demand for jet fuel and plastics means that an increasing amount of crude oil will be extracted and processed and refineries will continue to produce petrol from that crude.

    If the petrol is not used for transportation it will just be diverted to some other use, so there is no point in reducing demand for petrol if we don't also reduce demand for all the other products refined from a barrel of crude.

    I'm not qualified to dispute the figures and it all appears worryingly logical to me. It seems like if we don't address the world's increasing appetite for air travel and plastics we are all doomed.
    •  
      CommentAuthordjh
    • CommentTimeFeb 3rd 2017
     
    Interesting article and correct about the problems. But conversion of oil products is done all the time, so changing the product mix is certainly possible and will change the figures significantly.

    People do recognize the problem of storage of course and are researching and prototyping various solutions. People are researching and prototyping means to use other feedstocks than oil to make plastics, and indeed other feedstocks than oil to make hydrocarbon fuel.

    Not all old petrol/diesel cars will be reused elsewhere, and even if they are it only slows down their removal.

    So I think I'd need to see a lot more careful and integrated analysis before I believe that a continuing need for jet fuel together with a load of old cars presented an apocalypse all by itself.
    • CommentAuthorEd Davies
    • CommentTimeFeb 3rd 2017
     
    His company, St 1, covers about a fifth of the region's petrol retail network.
    So no point-of-view issues there, then?

    I have very mixed feelings about EVs. They're clearly better in many ways than directly fossil fuelled cars but they're not “the answer” because there isn't a single answer and they still have plenty of problems of their own. We need to be re-engineering society to move away from so much transport in the first place. When that's done EVs would be a less bad solution for some of what's still needed.

    I don't think it's anything like as simple as a certain amount of crude oil going in and a fixed amount of each of the products coming out - as I understand it there's a lot of processing going on which can convert one part to another in various ways.

    Still, the big thing is that we need to be cutting back on the amount of aviation fuel burned, too.

    Pretty much all the existing cars will be run to the end of their natural lives. The question is what is the mix in the next generation.
    • CommentAuthorringi
    • CommentTimeFeb 3rd 2017
     
    Sorry I care more about the local pollution in our town than I do about climate change. EV clearly reduce local pollution, without making climate change worse unless cars that are still in good working order are forced to be scrapped.

    As a first step I could like to see ALL taxis and mini cabs being EVs.
    • CommentAuthorwookey
    • CommentTimeFeb 11th 2017
     
    I care more about the local pollution in our town than I do about climate change


    One of these shortens some city-dwellers lives by a few days/weeks/months. The other could well cause complete civilisational collapse, or maybe 'only' worldwide misery, starvation, migration and war. So I'm not convinced about your priorities, but insofar as both these problems tend to have similar solutions, it may not actually matter much.

    You are not alone, so I forsee legal action to improve air-quality being a significant driver of decarbonisation activities over the next decade. Fine by me. Sooner the better. I await my 18-yr old diesel being made illegal in more places than just London.
    •  
      CommentAuthordjh
    • CommentTimeFeb 11th 2017
     
    Posted By: wookeyI await my 18-yr old diesel being made illegal in more places than just London.

    It's illegal in Singapore. Has been for many years ...
    •  
      CommentAuthorSteamyTea
    • CommentTimeFeb 11th 2017
     
    I have asked this question before, but never got a satisfactory answer ('Never answer the question that is asked of you. Answer the question that you wish had been asked of you". Robert McNamara)


    So I shall ask again, but in a different way.

    As we know the amount of energy that can be had from a chemical reaction via combustion in oxygen, and we use it ever day, do we now the maximum electrical energy we can get out of a non combustion chemical reaction.
    Or to put it simply, burn a kilo of gasoline and get about 10 kWh out of it, what is the best that we can get out of a chemical battery, in theory.
    Not out of some magical fusion reactor.
  2.  
    The guy is basically and fundamentally wrong. Probably.

    He is making the dubious assumption that if oil is not used in vehicles, it will be used anyway elsewhere, so whats the point?

    2 things spring to mind
    a) If the oil is used in, For example, plastics, it will last an awful lot longer before it turns into CO2
    b) His logic would be that if it is not used as fuel, it'll magically cause an increase in the other uses. A rather dubious assertation IMHO.
    • CommentAuthorbxman
    • CommentTimeFeb 11th 2017
     
    Still, the big thing is that we need to be cutting back on the amount of aviation fuel burned, too.


    It has got to be taxed on an international basis and soon

    If you have't just spend a moment to view

    https://youtu.be/DrCX_mawAmk

    some people have watched it I believe and AFAIK no-one has claimed it to be untrue.



    As a first step I could like to see ALL taxis and mini cabs being EVs.

    +!

    and most of those electric cars do not need to have sport car performance

    or a massive range so many are carting about a load of unwarranted weight quite unnecessarily.

    The EV's could be quite a bit cheaper with less weight and less battery.

    Car sharing should be encourage and possibly even subsidised so that people needing to do the occasional long journey could leave the EV for someone else to use .

    So many cars choking up our roads and only being used for for a few minutes in the day .

    mine now I suspect only gets used for 10 or 20 hours in the course of the year .
    • CommentAuthorwookey
    • CommentTimeFeb 12th 2017
     
    Here's a very interesting talk on the future of transport, considering the nexus of EVs, autonomous vehicles, sharing economy and mobile tech. Stefan Heck, talking at MIT, who certainly seems to know his stuff. Well worth taking an hour to watch IMHO, as there is a lot of useful data and some interesting ideas (You can skip the last 40 mins of questions).:

    https://www.youtube.com/watch?v=Pn9jgf6CXoc
    • CommentAuthorMikel
    • CommentTimeFeb 12th 2017
     
    @ST,

    Is this what you are looking for?
    https://en.m.wikipedia.org/wiki/Energy_density
    •  
      CommentAuthorSteamyTea
    • CommentTimeFeb 12th 2017
     
    Not quite Mike. That is what we can currently achieve (I think).
    I am more interested in the absolute maximum, then we can get an idea of how close we are to achieving that.
    Take an IC engine as an example. This currently produce about 30% of the energy content of the fuel as work, a Gas Turbine is a bit over 50%.
    So where are batteries compared to their theoretical maximum.

    I notice that a cheese and ham sandwich has an energy content of 2,815.9 Wh/kg.
    • CommentAuthorEd Davies
    • CommentTimeFeb 12th 2017
     
    Posted By: bxmanStill, the big thing is that we need to be cutting back on the amount of aviation fuel burned, too.

    It has got to be taxed on an international basis and soon
    Yep

    Posted By: bxmanIf you have't just spend a moment to view

    https://youtu.be/DrCX_mawAmk

    some people have watched it I believe and AFAIK no-one has claimed it to be untrue.
    It's actually a bit worse than he claims as he doesn't take into account the extra global-warming effect of emissions in the stratosphere which are something like double (estimates vary quite widely) those of the same amount at ground level.
    •  
      CommentAuthordjh
    • CommentTimeFeb 12th 2017
     
    The difficulty with car sharing is how to make it work. How to guarantee that if I book a car, it won't be vomit stained, smell of cigarettes or have broken crisps all over the floor? How to have my and my wife's travel possessions (sunglasses, maps, water, pen, spare money, shopping bags, umbrellas etc etc) conveniently stowed?

    And if you don't live in a city centre, how to get the car to me? (yes, yes, autonomous cars)
    • CommentAuthorMikel
    • CommentTimeFeb 12th 2017
     
    @ST,

    I did think my answer was too easy but had to check:-)

    I am sure you know how efficient electric motors are in converting electicity into work, around 80% or so. However, I'm not sure what you mean by theoretical efficiency of a battery. Could you expand?

    Mike
    •  
      CommentAuthorSteamyTea
    • CommentTimeFeb 12th 2017
     
    I can try to explain.
    For any given energy storage there is a theoretical maximum, bit like there is for a motor or a generator (think Betz Limit on wind turbines).
    Now we are not going to be refining better gasoline or diesel as they have got about as good as they can get.
    Batteries are a long way behind on energy density.
    But we know the Periodic Table quite well, and how different elements interact (though still a lot to know).
    So for any given combination of elements, we should be able to work out if an electrochemical process will happen.

    Disregarding the volatility of some of these reactions, what is the best combination of elements to generate electricity and what will the energy density be?

    Hope that is a bit clearer.
    • CommentAuthorMikel
    • CommentTimeFeb 12th 2017
     
    I am not anything like expert enough on battery technology to comment further. I am sure there will be further improvements because there is more investment. I am somewhat sceptical about any dramatically new chemistry that will produce a step change. Batteries have been around for a very long time and the need for electrolyte and electrodes will impose physical limits.
    •  
      CommentAuthorSteamyTea
    • CommentTimeFeb 12th 2017
     
    That is my feeling too.
    • CommentAuthorSprocket
    • CommentTimeFeb 13th 2017 edited
     
    What about supercapacitors?
    A little way to go yet but densities are going up and costs are falling at decent rates.
    And they are supposedly very green to manufacture and easy to recycle.

    And as a driving force for technology change electric vehicles surely have to be a better influence than fossil fuel combustion engines?
    • CommentAuthorringi
    • CommentTimeFeb 13th 2017
     
    Posted By: SteamyTeaFor any given energy storage there is a theoretical maximum


    Not if you are changing the chemistry and physics!

    There is no reason way battery+motor cannot be better then diesel+engine, it will just take lots of noble price winning discoveries to get there…
    • CommentAuthorringi
    • CommentTimeFeb 13th 2017
     
    Posted By: SprocketWhat about supercapacitors?


    Space and mass energy densities is not very good, and is unlikely to every be, however they can be charged/discharged VERY fast. So great for recovering energy from breaking etc if there cost come down.
    •  
      CommentAuthorSteamyTea
    • CommentTimeFeb 13th 2017
     
    Posted By: ringiNot if you are changing the chemistry and physics!
    That's what I want to know.
    I doubt if we are going to find any more stable elements that are stable. As we know the orbits of the elements in the periodic table, surely there is a combination that will give the best release of electrons.
    (I never really got to grips with chemistry)
    I doubt if there is any new Physics to be discovered in this field. Just more research.
    • CommentAuthorringi
    • CommentTimeFeb 14th 2017
     
    Firstly we have to define what a battery is….

    Let’s say it is something that can give electrical power output on demand and be recharged by plugging it into the main. Additionally I will allow it to use the air while charging or discharging, and to have a water tank that needs filling up at the time of charging. It must not give out any gases into the air that are not already there, and must reuse any gases it gives out – so it can give out CO2 while discharging providing it then uses up the CO2 while charging. (Or use 02 while discharging, and release it while charging.)

    Given the above, a fuel cell is a battery provided the car has a on-board system to make fuel from mains power!
    There is no reason the fuel cannot be as least as energy dance as diesel, we just need the correct catalyst to allow low temperature splitting (and recombining) of CO2 and H20 to make the fuel….

    Current batteries have very little of their mass (or size) used to store energy, most of it is used to encase the storage chemicals and to separate cathode from the anode. By using the oxygen in the air batteries can be half in size (google lithium-air battery).

    Therefore I expect we can get at least a tenfold improvement on what with have at present just by steady development of what we already have – this is more then we need for cars….
    • CommentAuthorMikel
    • CommentTimeFeb 14th 2017
     
    Posted By: Steamy Tea(I never really got to grips with chemistry)


    A pity! My difficulty is that it is at least 45 years since I studied any electrochemistry. Most of my time doing industrial research was as a 'pot boiler'.

    I think what ST is trying to say is that we know the layout of the periodic table according to the electrons filling the s,p,d and f shells (probably should be explaining this in terms of the Schrodinger wave equation) and as a result we know the theoretical basis for the ionisation energies of the elements.

    Since we have had this knowledge for a long time, I am doubtful that much more than decreasing incremental progress will be made through selecting different elements.

    More likely progress will be made through further development of organic electrolytes/redox reactions. These may have more scope for bringing costs down. We should see improvements to the lifetimes of batteries and improved scalability. Manufacturing costs should come down as well. I am thinking flow batteries here.

    I think it unlikely that there will be a totally equivalent replacement for the internal combustion engine. My experience of introducing new technology is that the first attempts are to replicate existing systems. There are gradually abandoned and totally new systems developed. This is likely to lead to some consequential behavioural change (welcome or not!).

    Going back to the original reference quoted by Chris Bacon, I don't think that EVs will 'solve' climate change but they are a step on the way. What was missing from the article was any consideration of how long we will have affordable oil and that oil's use for shipping is probably of greater importance than aviation.

    Looking further out, we live on a finite planet with finite resources. Unless we as a race come to terms with that and change, our time in the sun is not going to last.
    • CommentAuthorSprocket
    • CommentTimeFeb 14th 2017 edited
     
    Posted By: ringi
    Posted By: SprocketWhat about supercapacitors?


    Space and mass energy densities is not very good, and is unlikely to ever be, however they can be charged/discharged VERY fast. So great for recovering energy from breaking etc if there cost come down.


    I would not be so sure. Tungsten oxide has demonstrated up to 100Wh/kg already, with graphene not far behind and potentially way cheaper and with plenty of headroom left yet ... ie. around the same storage density as the lower end of the range for Lithium Ion.
    And in combination with other power technologies they may open up a whole range of new options.
    There are also various battery/capacitor hybrids (ie. not combinations of battery+caps but electrochemical cells with tech adapted from supercapacitors) in development that will offer some advantages of both.

    I expect there will be plenty of dramatic changes in battery chemistry in the next couple of decades given all the impetus from new market uses. eg. Not really vehicle based but...
    https://www.seas.harvard.edu/news/2017/02/long-lasting-flow-battery-could-run-for-more-than-decade-with-minimum-upkeep
    • CommentAuthorringi
    • CommentTimeFeb 14th 2017
     
    I just don't see supercapacitors being use in electric cars much, remember that every year Lithium Ion gets better, sells more, and has more spend on research due to the increased sales (and the loop repeats).

    An electric bus or tram that charges at every stop is a different case, as the very fast charging of supercapacitors beats lithium ion hands down.

    I am expect flow batteries to give lthium Ion competition for large scale storage, and maybe even for applications like LGV by pumping out that tanks, so giving a VERY fast charge. I wish I could believe that flow batteries would become cost effective for seasonal storage as that would be a game changer.....
    • CommentAuthorEd Davies
    • CommentTimeFeb 16th 2017
     
    Slight twist of topic: apparently the Daily Mail [¹] claimed that if we went to completely EVs then 20 new nuclear power stations would be required. The usual EV cheerleaders [²] poo-poohed it and it seems the Times has apologized for its version of the story [³]. Somewhere else I saw comment that it was a kW vs kWh mixup - possibly.

    One argument made against it was that EVs would take power from the grid off peak so no or little extra generation capacity would be required. This rather misses the point that EVs, while good from the particulate and other local pollution points of view, are likely also to be part of a wider decarbonisation strategy which will including electrifying other things such as space and DHW heating which will also likely be off peak.

    My calculation: 25 million EVs, 20'000 km/year·vehicle, 5 km/kWh, 8'000 hours per year = 500 W/vehicle = 12.5 GW total extra average grid generation needed. You can offset a bit of that with less energy use in the processing of crude oil into petrol and transporting it to filling stations, etc, but I suspect that's not going to knock off more than the 0.5 GW on the end.

    Anyway, 12.5 GW is not far short of 20 nuclear *reactors* - power stations often have multiple reactors and I think the common boiling water ones are often around 800 MW per reactor with usually two in the power station. See, for example, Hinkley B which has two 660 MWe reactors [⁴].

    You can also fiddle around as much as you like with what time you charge cars and with car batteries being used to reduce demand during peaks but still that extra electricity has to be generated somewhere and sometime.

    Personally I think that's a good trade off against the problems of internal combustion engines but still we shouldn't kid ourselves that EVs are somehow virtuous: just somewhat less harmful than the alternative.

    [¹] https://t.co/42ydpugKsv is said to be a link to the article - nope, not going to click on that myself.

    [²] https://twitter.com/bobbyllew/status/831283739946737665 https://twitter.com/QuentinWillson/status/830759292240265216

    [³] https://twitter.com/dpeilow/status/831717762259099648

    [⁴] https://en.wikipedia.org/wiki/Hinkley_Point_B_Nuclear_Power_Station#Specification
    • CommentAuthorringi
    • CommentTimeFeb 16th 2017
     
    Even if we generate 100% of the additional electricity using large diesel generators I believe the EV are a net gain, as the large diesel generators can operate at full load without having to speed up and slow down all the time.

    But we can then use wind power so we don’t use the diesel generators for as many hours a year. (I like diesel generators as they have a low capital cost, but a high running cost hence we can build then even if we assume that most of the year they will not be in use. So they don’t stop renewable from being cheaper.)

    Personally I would be happy with lots of new nukes, as they seem to kill a lot less people then the pollution from cars. However no company is able to mass produce nuke power stations, hence they still cost too much……
    • CommentAuthorEd Davies
    • CommentTimeFeb 16th 2017
     
    Posted By: ringiEven if we generate 100% of the additional electricity using large diesel generators I believe the EV are a net gain, as the large diesel generators can operate at full load without having to speed up and slow down all the time.
    I think I probably agree, mostly. Not least because large diesel generators can likely have better and better maintained emissions controls, be away from spraying their emissions directly in people's faces and there's at least the potential for some carbon capture. But that's not an excuse for saying that EVs won't need any more generation than would otherwise be needed.
    • CommentAuthorbillt
    • CommentTimeFeb 16th 2017
     
    If you wanted to electrify all road transport you'ld need a lot more than that.

    According to https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/573269/ECUK_November_2016.pdf the UK used 40,521 ktoe (kilo tonnes oil equivalent) for road transport in 2015. That converts to 471,260 GWhr or 54GW of generating capacity running continuously.

    Posted By: ringiEven if we generate 100% of the additional electricity using large diesel generators I believe the EV are a net gain, as the large diesel generators can operate at full load without having to speed up and slow down all the time.


    That's highly unlikely. Modern oil using transport engines are remarkably efficient, not as efficient as a large fixed diesel, but not far behind. Unfortunately there are a lot of significant losses involved in any grid based system. There are the losses in distribution 5-10%, the losses in battery charge /discharge (10-20%) the losses in the car motors (?) plus the fact that batteries self discharge so there will be standing losses in an unused vehicle. AFAICS the overall efficiency of current electric vehicles is very similar, possibly worse than, burning oil based fuel in the vehicle directly, despite propaganda from the EV industry.
   
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