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Why haven't we reached higher mpg cars?

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    (Original post by Dan1909)
    True, however there's fairly unbreakable limits on how much biofuel you can produce from a kg of biomass due to the chemical make-up of the material. Currently the work is being done to engineer specific plants to grow in ways that will produce the most convertible biomass per unit area, however the limits will always be there, so there's not that much room for improvement. The planting to harvest time will always be roughly the same as well.

    Yeah there will always be other materials required, but in general they're on manageable levels. For example the amount of platinum required to make the catalytic converters in every car fitted with one is huge, however it's manageable.
    That's fine, so you increase the yield of the biomass. Or find an alternative method - I overheard something the other day about something that photosynthesised petrol directly. Or grow in the oceans. Plenty of problems, sure, but we're hardly there yet with electric vehicles. Of course the other advantage is that a new fuel could be used in trucks, tractors, aircraft, ships, trains - applications which aren't feasible for batteries.
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    (Original post by CurlyBen)
    That's fine, so you increase the yield of the biomass. Or find an alternative method - I overheard something the other day about something that photosynthesised petrol directly. Or grow in the oceans. Plenty of problems, sure, but we're hardly there yet with electric vehicles. Of course the other advantage is that a new fuel could be used in trucks, tractors, aircraft, ships, trains - applications which aren't feasible for batteries.
    Trucks and aircraft could be run easily off of batteries, and trains are a non issue with their power feed already. Tractors may be more difficult, only for the reason that power feeds may be harder to get hold of in remote fields or anything.

    My point about the biomass was there are fixed limits to the yield you can get, not just from the size of the crops, but from the land area available, the time taken to grow and harvest them, and the amount of crop that can be planted in any area. The limits can, and will always be pushed, and new ways found, but there simply wouldn't be enough land available to produce all the world's requirements.

    The idea of directly producing petrol from bacteria is one of the holy grail ideas, similar to finding a material capable of catalytic photo-dissociation of water on a decent efficiency. It's something that could change the world overnight, but isn't expected any time soon sadly .
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    (Original post by Dan1909)
    Trucks and aircraft could be run easily off of batteries, and trains are a non issue with their power feed already. Tractors may be more difficult, only for the reason that power feeds may be harder to get hold of in remote fields or anything.
    The big issue with trucks and tractors is that they already run at close to peak power output all the time, whereas cars run at low percentages of peak output. That means you need to store a lot more energy than you do for cars. Trains in the UK mainly run on electrified track, but I can well believe that some areas of the US or China it's simply not feasible to electrify as the distance involved and the traffic frequency wouldn't make it justifiable.

    Planes.. I don't think they will ever be electric, as there are issues there which aren't addressed by simply having better batteries. Firstly, planes get lighter as they burn off fuel, which reduces the fuel load required - that doesn't happen with batteries. Also the maximum take off weight is well above maximum landing weight, which is why aircraft having to return to the airport they departed from in case of a minor emergency often fly around for hours to burn off fuel. Then you have the issue of energy density - not only do you have to haul the weight of batteries into the sky, they'd be mounted in the wings which are cantilevered. Any extra weight in the wing would have to be made up for by additional stiffening of the wing, which adds weight, which increases battery requirements. Then what would your propulsor be? Even if you could get a motor large enough to spin a turbofan, and it was small enough to fit into the profile of a turbine (unlikely given the power density of turbines, but we'll assume it can) you still have the problem that a turbine is mostly air and a motor is mostly metal, so would be very, very heavy. Then you've got to get airworthiness certificates, and that doesn't happen until technology's been around for donkey's years - they've only just started to certify composites on airliners.





    My point about the biomass was there are fixed limits to the yield you can get, not just from the size of the crops, but from the land area available, the time taken to grow and harvest them, and the amount of crop that can be planted in any area. The limits can, and will always be pushed, and new ways found, but there simply wouldn't be enough land available to produce all the world's requirements.

    The idea of directly producing petrol from bacteria is one of the holy grail ideas, similar to finding a material capable of catalytic photo-dissociation of water on a decent efficiency. It's something that could change the world overnight, but isn't expected any time soon sadly .
    I'm sorry but this argument is having your cake and eating it. You're claiming that it's certain batteries will improve by orders of magnitude, but other technologies are at their limits? I think perhaps you ought to open your mind a little more.
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    (Original post by Dan1909)
    I don't think you do.

    I never take this attitude with anyone who disagrees with me. However, you're not disagreeing with me, you're denying simple facts. I honestly don't understand how you don't realise this, if you know the topic as well as you say you do. Or, more likely, you're just trolling now.
    No i'm not. I'm disagreeing with you stating facts that aren't facts at all, they are your opinions.
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    (Original post by RyanT)
    Swap batteries at battery swap stations.

    Essentially what we do with fuel stations and solves all the range problems.
    How many battery swap stations will we need for 20m cars?
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    (Original post by walterwhite123)
    How many battery swap stations will we need for 20m cars?
    I don't think that's a number that anyone can calculate yet, too many variables. No more than the number of petrol stations though, less probably.


    (Original post by walterwhite123)
    No i'm not. I'm disagreeing with you stating facts that aren't facts at all, they are your opinions.
    I'm just going to ignore you now, troll. I've explained my point thoroughly, you standing there and posting "zomg opinions" is just wasting my time till you have something to back it up with. Find some facts that go against what I've said, and maybe you'll have some credibility.
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    (Original post by CurlyBen)
    The big issue with trucks and tractors is that they already run at close to peak power output all the time, whereas cars run at low percentages of peak output. That means you need to store a lot more energy than you do for cars. Trains in the UK mainly run on electrified track, but I can well believe that some areas of the US or China it's simply not feasible to electrify as the distance involved and the traffic frequency wouldn't make it justifiable.

    Planes.. I don't think they will ever be electric, as there are issues there which aren't addressed by simply having better batteries. Firstly, planes get lighter as they burn off fuel, which reduces the fuel load required - that doesn't happen with batteries. Also the maximum take off weight is well above maximum landing weight, which is why aircraft having to return to the airport they departed from in case of a minor emergency often fly around for hours to burn off fuel. Then you have the issue of energy density - not only do you have to haul the weight of batteries into the sky, they'd be mounted in the wings which are cantilevered. Any extra weight in the wing would have to be made up for by additional stiffening of the wing, which adds weight, which increases battery requirements. Then what would your propulsor be? Even if you could get a motor large enough to spin a turbofan, and it was small enough to fit into the profile of a turbine (unlikely given the power density of turbines, but we'll assume it can) you still have the problem that a turbine is mostly air and a motor is mostly metal, so would be very, very heavy. Then you've got to get airworthiness certificates, and that doesn't happen until technology's been around for donkey's years - they've only just started to certify composites on airliners.






    I'm sorry but this argument is having your cake and eating it. You're claiming that it's certain batteries will improve by orders of magnitude, but other technologies are at their limits? I think perhaps you ought to open your mind a little more.
    Hardly. I'm simply stating things the way they are. There are limits on biomass production which are pretty impossible to get around. The limits on battery technology is unknown, but well within the region of what I've said is required.

    So no, I'm not doing anything of the sort. All I've relayed to you here are the facts that are currently being put round publicly.

    As for the issue with planes, the weight issue isn't an issue at all, as newer generations (if they were to use batteries) would simply be designed with the weight in mind. I'll openly admit that planes/trucks/tractors isn't the areas that I have worked in, so I don't know anywhere near as much about them, so I've tried to avoid talking about them too much.
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    (Original post by RJ555)
    Many years ago there was a scarcely released VW Lupo that "apparently" received 92-99mpg. There are of course cars like the new Kia Rio claiming 88mpg (which seems the highest of current cars in the UK) as well as electrics (the sky high 120+mpg advertised by the Ampera) and hybrids of course.

    Most cars however seem to be stuck in a more conservative 50-60mpg range. Obviously weight must be a factor, but there seem to be plenty of diesel superminis struggling to break these barriers.

    What exactly is holding the majority of diesel cars back, or is it more the case of false advertisement at the higher end of the spectrum?
    Because, until recently, all research was directed at reducing the CO2 and NOX levels in the internal combustion engine. Making engine more greener, was the main goal.
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    Future is likely hydrogen fuel cells - they are a lot cheaper than they used to be, the platinum in them can be recycled so there is very little impact on environment and also sustainable compared to heavy metal batteries. You can fit 300kgs of hydrogen into a conventional fuel tanker but obviously a bespoke design would carry more. The hydrogen won't be used as a fuel, per se, but rather as a medium, with the vehicles able to run in reverse whilst plugged into the wall, creating hydrogen from water and storing it onboard. Alternatively refueling on the road can take seconds from a pressurised tank.
    Unfortunately the problems with this are that the hydrogen still requires electricity to generate. Just now it works out cheaper but worse for the environment to steam reform methane, usually sourced from fossil fuels. When renewable sources of electricity become cheaper (relative to oil), it should be common to use hydrogen instead of batteries.
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    (Original post by walterwhite123)
    How many battery swap stations will we need for 20m cars?
    How many petrol stations do we need for 20m cars?

    The buildings and facilities are already there, just swap the big petrol tanks for racks of batteries.

    You could imagine driving in to an auto-washer style machine, it scans your car to get your make/model and calls up an appropiate battery from a rack underground.

    The battery swapper machine then sends a code for your bonnet to pop up, which you approve inside the car. Robotic arms remove your current battery, a recharged one is put in. Some quick quality tests on your old battery and you're driving away faster then if you were filling up a tank of liquid.



    The stations are already there...
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    (Original post by Dan1909)
    Hardly. I'm simply stating things the way they are. There are limits on biomass production which are pretty impossible to get around. The limits on battery technology is unknown, but well within the region of what I've said is required.

    So no, I'm not doing anything of the sort. All I've relayed to you here are the facts that are currently being put round publicly.

    As for the issue with planes, the weight issue isn't an issue at all, as newer generations (if they were to use batteries) would simply be designed with the weight in mind. I'll openly admit that planes/trucks/tractors isn't the areas that I have worked in, so I don't know anywhere near as much about them, so I've tried to avoid talking about them too much.
    No, you're stating your opinion as fact. How about if there was a crop that would produce 300 times as much oil as conventional crops, with a harvest period of 1-10 days, which could be grown on arid areas and other areas unsuitable for conventional crop cultivation? What a shame algae doesn't exist. It's a real pity they aren't expecting yields of 1000 US gallons of oil per acre from it.

    Here's another interesting little snippet of info for you. I used to work on a ship driven by 6MW electric motors. Approximate dimensions maybe 5m tall by 10m x 10m, weight probably in excess of 100 tons. Power output of an aircraft turbine isn't a simple concept and is normally expressed in terms of thrust, but the industrial variant of the Trent is rated for 64MW. Therefore to have a motor that could realistically replace a turbine you would need a reduction in size of an order of magnitude whilst also increasing power output by an order of magnitude - or improving the performance of a motor by 2 orders of magnitude (even without considering the auxiliary equipment, such as syncros, needed to run the motor). That just isn't going to happen, so unless you want an aircraft the size of a 747 that can just about fly 30 miles with only the pilot onboard, another fuel will be needed. I realise you've avoided talking about things that don't fit your argument, but if you can't replace all current IC applications with electric alternatives then there must be another alternative. If you have another viable alternative, there's no reason electric power will dominate instead of an alternative (and I'm by no means suggesting the only alternative is biofuel).

    Anyway, I'm sure you'll tell me I'm wrong again, and repeat your opinion that electric vehicles are the only future vehicle, but it's getting pretty boring. I won't reply to you again.
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    (Original post by CurlyBen)
    No, you're stating your opinion as fact. How about if there was a crop that would produce 300 times as much oil as conventional crops, with a harvest period of 1-10 days, which could be grown on arid areas and other areas unsuitable for conventional crop cultivation? What a shame algae doesn't exist. It's a real pity they aren't expecting yields of 1000 US gallons of oil per acre from it.

    Here's another interesting little snippet of info for you. I used to work on a ship driven by 6MW electric motors. Approximate dimensions maybe 5m tall by 10m x 10m, weight probably in excess of 100 tons. Power output of an aircraft turbine isn't a simple concept and is normally expressed in terms of thrust, but the industrial variant of the Trent is rated for 64MW. Therefore to have a motor that could realistically replace a turbine you would need a reduction in size of an order of magnitude whilst also increasing power output by an order of magnitude - or improving the performance of a motor by 2 orders of magnitude (even without considering the auxiliary equipment, such as syncros, needed to run the motor). That just isn't going to happen, so unless you want an aircraft the size of a 747 that can just about fly 30 miles with only the pilot onboard, another fuel will be needed. I realise you've avoided talking about things that don't fit your argument, but if you can't replace all current IC applications with electric alternatives then there must be another alternative. If you have another viable alternative, there's no reason electric power will dominate instead of an alternative (and I'm by no means suggesting the only alternative is biofuel).

    Anyway, I'm sure you'll tell me I'm wrong again, and repeat your opinion that electric vehicles are the only future vehicle, but it's getting pretty boring. I won't reply to you again.
    Like I already said, if you'd bothered to read it, I don't know or claim to know much about the suitability of electric planes, so I've not commented on them much. However, there are already some in production, small scale aircraft, but they exist. How easy it would be to scale that up, I don't know.

    Your "point" about the crop with a 10 day harvest time, are you actually claiming that as a feasible idea? Because it really isn't. Year 6 science project idea maybe, actual idea, not a chance.

    You've still yet to provide me with any evidence that any of those have any actual consideration to be put into practice, so, on you trot troll
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    (Original post by Dan1909)
    I don't think that's a number that anyone can calculate yet, too many variables. No more than the number of petrol stations though, less probably.




    I'm just going to ignore you now, troll. I've explained my point thoroughly, you standing there and posting "zomg opinions" is just wasting my time till you have something to back it up with. Find some facts that go against what I've said, and maybe you'll have some credibility.
    Where are the facts you posted?
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    (Original post by RyanT)
    How many petrol stations do we need for 20m cars?

    The buildings and facilities are already there, just swap the big petrol tanks for racks of batteries.

    You could imagine driving in to an auto-washer style machine, it scans your car to get your make/model and calls up an appropiate battery from a rack underground.

    The battery swapper machine then sends a code for your bonnet to pop up, which you approve inside the car. Robotic arms remove your current battery, a recharged one is put in. Some quick quality tests on your old battery and you're driving away faster then if you were filling up a tank of liquid.



    The stations are already there...
    How do all the petrol cars fill up in the meantime? Or are you suggesting that one day we suddenly say 'right that's it' and ban all petrol/diesel cars and convert petrol stations overnight?
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    (Original post by Dan1909)
    Like I already said, if you'd bothered to read it, I don't know or claim to know much about the suitability of electric planes, so I've not commented on them much. However, there are already some in production, small scale aircraft, but they exist. How easy it would be to scale that up, I don't know.

    Your "point" about the crop with a 10 day harvest time, are you actually claiming that as a feasible idea? Because it really isn't. Year 6 science project idea maybe, actual idea, not a chance.

    You've still yet to provide me with any evidence that any of those have any actual consideration to be put into practice, so, on you trot troll
    I love your thinking. Anyone who doesn't agree with you is a troll. Brilliant.
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    (Original post by walterwhite123)
    How do all the petrol cars fill up in the meantime? Or are you suggesting that one day we suddenly say 'right that's it' and ban all petrol/diesel cars and convert petrol stations overnight?
    Wow, you don't seem to be very clever or imaginative.

    Hint: Having both facilities is not mutually exclusive and dual purpose stations could exist.

    Look up "transition" in dictionary.
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    (Original post by RyanT)
    Wow, you don't seem to be very clever or imaginative.

    Hint: Having both facilities is not mutually exclusive and dual purpose stations could exist.

    Look up "transition" in dictionary.
    Where do the petrol stations get all this magic space from then?
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    (Original post by walterwhite123)
    Where do the petrol stations get all this magic space from then?
    Reduce 12 pumps to 8.

    This is like stealing sweets off a small child lol.
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    (Original post by Friggerpants)
    I reckon it'll go the way of diesel-electric..........Little diesel generator, powering batteries and electric motors!
    From what I've read that sounds a bit like the Ampera (runs of electric, then a diesel engine generates more electricity when the batteries out). But then again the Ampera advertising is very cloudly so I may have misunderstood.

    EDIT: My mistake, petrol engine, but same principle: engine fuels the battery so "technically" its a fully electric vehicle?
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    (Original post by walterwhite123)
    How many battery swap stations will we need for 20m cars?
    Just set up battery swap points at existing petrol stations.

    Problem is we'd need a standardised battery and at the moment each manufacturer has their own design.

    (Original post by walterwhite123)
    Where do the petrol stations get all this magic space from then?
    Fewer pumps, remove the automatic car wash, convert part of the building to accommodate them...

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