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Plug in hybrids - Talk to me watch

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    Wrong Fonejacker character for the title I guess

    Just wondering if any one could give us a bit more info on these type of cars?

    I had a look here:
    http://www.nextgreencar.com/new-car-search/

    And well you get cars like the Chevrolet VOlt and the Vauxhall Ampera offering impressive Mpg (equivalent) of around 235Mpg, but these vehicles also have an electric only range of something like 50 or 70 miles,and then it differs from car to car etc...

    And well, after that of course, they'd start to use their petrol engine, but they don't always show what sorta fuel efficiency you'd get after the electric range has been depleted?

    I can't really afford one of these cars, but it's more that Im trying to "understand" these cars, in relation to fuel economy

    In other news, I no longer get this:
    http://www.bbc.co.uk/news/uk-england-london-23125082

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    Really skeptical about those actually doing such a mpg.

    Especially with news, forgot which model, but batteries on another car model after a year being severely comprised in terms of what it can charge, and its apparently so bad, that the car people have bought is a bit pointless, as the battery can hold less 50-70% of the charge after a year, and getting a new battery is very very expensive.

    I suspect the same with the electric side with these cars..........battery technology is way behind to yield any proper progress, they need to be able to hold far more, and be far more durable.
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    (Original post by Iqbal007)
    Really skeptical about those actually doing such a mpg.

    Especially with news, forgot which model, but batteries on another car model after a year being severely comprised in terms of what it can charge, and its apparently so bad, that the car people have bought is a bit pointless, as the battery can hold less 50-70% of the charge after a year, and getting a new battery is very very expensive.

    I suspect the same with the electric side with these cars..........battery technology is way behind to yield any proper progress, they need to be able to hold far more, and be far more durable.
    Well, I guess it could kinda work like the hybrid batteries work now ie: continuous power. Tbf, a lot of money is being put in to batteries atm, and yes they can be expensive when they go.

    These ones are part hybrid power as well, as well as plugins. I'm still rather confused about the whole thing tbh
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    (Original post by de_monies)
    Well, I guess it could kinda work like the hybrid batteries work now ie: continuous power. Tbf, a lot of money is being put in to batteries atm, and yes they can be expensive when they go.

    These ones are part hybrid power as well, as well as plugins. I'm still rather confused about the whole thing tbh
    You should see the price of the complete battery powered ones......recent model in states has been seriously draining and cant keep charge and price to put in a new battery is nearly the same price as the car. Been a investigation, forgot which company, but I would be wary.
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    An economically pointless endeavour imo. By all means people can buy one if it makes them feel like they're doing their bit for society but they're more expensive and worse than a combustion engined car in almost every aspect.

    I'd like to see some figures on efficiency regarding these. A coal fired power station is only around 50% efficient, what is a petrol or diesel car? Cars have catalytic converters, do power stations?

    Battery tech is still too poor imo, if you buy one of these cars now, yore investing in the battery companies to use your money to improve them for the future but right now they aren't delivering the economy cost wise that they should be. Everyone has seen the effects of battery capacity in phones, cameras, ipods etc, these cars use the exact same tech but on a larger scale.
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    (Original post by james1211)
    An economically pointless endeavour imo. By all means people can buy one if it makes them feel like they're doing their bit for society but they're more expensive and worse than a combustion engined car in almost every aspect.

    I'd like to see some figures on efficiency regarding these. A coal fired power station is only around 50% efficient, what is a petrol or diesel car? Cars have catalytic converters, do power stations?

    Battery tech is still too poor imo, if you buy one of these cars now, yore investing in the battery companies to use your money to improve them for the future but right now they aren't delivering the economy cost wise that they should be. Everyone has seen the effects of battery capacity in phones, cameras, ipods etc, these cars use the exact same tech but on a larger scale.
    Tbqh, agreed, but I thought considering this was the motoring section, people would be able to educate me somewhat on the cars. I don't exactly have the capital to buy one of those cars, and tbh I'm considering (in say 5 years time) at getting something like this:

    http://www.nextgreencar.com/view-car...Semi-automatic

    (But then I thought hmmm... Citroen.... French....), so maybe either this:
    http://www.nextgreencar.com/view-car...osuly-Variable

    or this:
    http://www.nextgreencar.com/view-car...Manual-6-speed

    (depending on the size of the car)

    ie: Im guessing they should be around half their price in 5 years time.
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    Forget those and get a BlueMotion LED.
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    (Original post by james1211)
    Forget those and get a BlueMotion LED.
    A what?
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    (Original post by de_monies)
    A what?
    VW Golf BlueMotion Low Emission Diesel. 75mpg and it's just a normal diesel car.
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    (Original post by james1211)
    VW Golf BlueMotion Low Emission Diesel. 75mpg and it's just a normal diesel car.
    Oooh. According to this article:

    http://www.carmagazine.co.uk/Drives/...13-CAR-review/

    Some models gets 88.3Mpg combined (on paper) Wow. Wikipedia is also pretty interesting

    https://en.wikipedia.org/wiki/Volkswagen_Golf_Mk7

    That's pretty good! And you don't run the risk of your battery failing, and you get a large car (is it?) and it's a VW, though one thing and the only thing that could *possibly* put me off, is if it's an estate (Depends on how estate-y it looks I guess)

    Not *massively* fussed about low emissions, because well London no longer cares for exempting cars that produce higher than 75g/km for C02 emissions, and it still puts it in car tax band A (for the time being)
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    (Original post by james1211)
    An economically pointless endeavour imo. By all means people can buy one if it makes them feel like they're doing their bit for society but they're more expensive and worse than a combustion engined car in almost every aspect.

    I'd like to see some figures on efficiency regarding these. A coal fired power station is only around 50% efficient, what is a petrol or diesel car? Cars have catalytic converters, do power stations?

    Battery tech is still too poor imo, if you buy one of these cars now, yore investing in the battery companies to use your money to improve them for the future but right now they aren't delivering the economy cost wise that they should be. Everyone has seen the effects of battery capacity in phones, cameras, ipods etc, these cars use the exact same tech but on a larger scale.
    A petrol car is about 27pc efficient and a diesel about 32pc.

    Most of the energy from petrol is expelled as heat.

    Heavy plant is more efficient because the waste heat is reused.

    Electric cars are a waste of time.

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    (Original post by gbduo)
    A petrol car is about 27pc efficient and a diesel about 32pc.

    Most of the energy from petrol is expelled as heat.

    Heavy plant is more efficient because the waste heat is reused.

    Electric cars are a waste of time.

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    Is the efficiency level really as low as 27 - 32 percent? Wow. It's rather something that the motor industry hasn't made engines more efficient in the last few decades, if that's what you're getting at?

    Like with computers, you have the "80 plus" certification, which means that manufacturers have to make power supplies that are at least 80% efficient, to get that badge, and then there's badges,like bronze, silver, gold, titanium etc... for more and more efficient power supplies, and tbh in the space of around 6 years or so, efficiency has greatly improved.

    Once upon a time, the "average" power supply was around 65% efficient, and today it's closer to 90 - 95%

    Sorry I went off on a tangent there, but it's just me showing my shock if car engines are THAT inefficient if they are?
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    Internal combustion engines are incredibly inefficient because most of the energy is wasted as heat and noise. And to an extent light inside the engine.

    Engines are much more efficient than they used to be, if you look at the hp/ltr figures now compared to 20 years ago, then there have been huge advances.

    But they are still very inefficient. Petrol gives off 43MJ/Kg of energy, and you are getting only 12ish of that. A lot of energy wasted.

    Not really sure how you could re use the heat though.

    You could use regenerative braking more to bring up the overall efficiency, but engine efficiency in a IC engine is always going to be low until you can recycle the heat.
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    (Original post by de_monies)
    Is the efficiency level really as low as 27 - 32 percent? Wow. It's rather something that the motor industry hasn't made engines more efficient in the last few decades, if that's what you're getting at?

    Like with computers, you have the "80 plus" certification, which means that manufacturers have to make power supplies that are at least 80% efficient, to get that badge, and then there's badges,like bronze, silver, gold, titanium etc... for more and more efficient power supplies, and tbh in the space of around 6 years or so, efficiency has greatly improved.

    Once upon a time, the "average" power supply was around 65% efficient, and today it's closer to 90 - 95%

    Sorry I went off on a tangent there, but it's just me showing my shock if car engines are THAT inefficient if they are?
    Just think of the temperature of engines - 90 degrees I think they run at normally, that's an enormous amount of energy being lost as heat!
    It's amazing how inefficient some things are - light bulbs, only 10% efficient...

    I'd say the internal combustion engine has improved loads, and now it isn't going to get much higher than 30 odd percent. The only way to get a higher efficiency is to use a different mechanism, which is why there's so much investment into electric and hybrid cars - none of which (imo) are worth it yet.
    There's plenty of 'normal' cars on sale today which I think are better than electric/battery vehicles. Oh and the prices of these cars too are monstrous...
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    (Original post by Rump Steak)
    Just think of the temperature of engines - 90 degrees I think they run at normally, that's an enormous amount of energy being lost as heat!
    It's amazing how inefficient some things are - light bulbs, only 10% efficient...

    I'd say the internal combustion engine has improved loads, and now it isn't going to get much higher than 30 odd percent. The only way to get a higher efficiency is to use a different mechanism, which is why there's so much investment into electric and hybrid cars - none of which (imo) are worth it yet.
    There's plenty of 'normal' cars on sale today which I think are better than electric/battery vehicles. Oh and the prices of these cars too are monstrous...
    Perhaps, but consider the temperature of CPU's. For a lot of CPU's 70 degrees is "normal" I realise that we're talking about smaller things here, but once upon a time, CPU's were massive, and must have ran even hotter. Any way, my point is, that CPU's are pretty efficient

    Are light bulbs (the CFL's) only 10% efficient? I don't think they are, when they're cool to touch?

    Hmm it'd be interesting to see what they come up with. Well, hybrid cars aren't *that* pricey. I mean my hybrid cost me £3700 and you can pick up a 2006 Prius for around 5 - 6K

    But I guess electric cars can be quite expensive. Im waiting for that VW bluemotion to become cheaper It does sound pretty good!

    (Original post by james1211)
    VW Golf BlueMotion Low Emission Diesel. 75mpg and it's just a normal diesel car.
    Hmm only issue with that, is that it might *possibly* be small

    http://www.nextgreencar.com/view-car...Manual-5-speed

    but maybe Im used to driving a Honda Civic hybrid, and I guess my seats don't go down whilst the BlueMotion does I think
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    Electronics are much much much more efficient as you don't lose mechanical energy as friction.
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    (Original post by de_monies)
    Is the efficiency level really as low as 27 - 32 percent? Wow. It's rather something that the motor industry hasn't made engines more efficient in the last few decades, if that's what you're getting at?

    Like with computers, you have the "80 plus" certification, which means that manufacturers have to make power supplies that are at least 80% efficient, to get that badge, and then there's badges,like bronze, silver, gold, titanium etc... for more and more efficient power supplies, and tbh in the space of around 6 years or so, efficiency has greatly improved.

    Once upon a time, the "average" power supply was around 65% efficient, and today it's closer to 90 - 95%

    Sorry I went off on a tangent there, but it's just me showing my shock if car engines are THAT inefficient if they are?
    There's two issues here: firstly, what is meant by efficiency, and secondly what you're measuring the efficiency of.

    Efficiency is defined as the ratio of useful energy you get out of a device to energy you put in. As gbduo's already said that's a problem with engines as they tend to waste a lot of energy as heat. As a rule of thumb efficiency tends to increase with displacement as the surface area to volume ratio decreases and piston velocity decreases. That probably sounds counter-intuitive as efficiency with cars is normally taken as how far will a certain amount of fuel get you, which brings in a whole range of other factors, such as weight, driving style, terrain, auxiliaries etc.
    The big problem is that heat generation isn't an unwanted byproduct of the process, as it is with a transformer, but it's integral to how the process functions. The only way to get a proper step change in efficiency is to devise a process that can extract energy from a potential energy source without converting to heat first. Hydro electric is one method, and I believe hydrogen fuel cells are another - the problem is obtaining the potential energy, which in both cases generally relies on a conventional, heat generating power source.

    Secondly, your power supply example isn't really comparable to a car. It's just one component in a chain - to make any kind of meaningful comparison you'd have to start at the prime mover (the power station) and factor in transmission losses etc. right through to your output - and I'm not sure how you would quantify the useful power output of a computer. When you factor all that in the whole system may well be down to the 30% efficiency bracket. Your power supply comparison would be better applied to a gearbox or differential, where you could well be seeing 90% or so efficiency.

    And if you think it's so shocking that engines waste so much energy as heat, big engines in low speed applications might be using 10% of their useful output running a fan to get rid of the excess heat!
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    (Original post by Rump Steak)
    Just think of the temperature of engines - 90 degrees I think they run at normally, that's an enormous amount of energy being lost as heat!
    It's amazing how inefficient some things are - light bulbs, only 10% efficient...

    I'd say the internal combustion engine has improved loads, and now it isn't going to get much higher than 30 odd percent. The only way to get a higher efficiency is to use a different mechanism, which is why there's so much investment into electric and hybrid cars - none of which (imo) are worth it yet.
    There's plenty of 'normal' cars on sale today which I think are better than electric/battery vehicles. Oh and the prices of these cars too are monstrous...
    Your water coolant and liners are at 90ish degrees, but your exhaust gas temp is closer to 1000 degrees at high load and oil temperatures around 120 degrees. That is where the heat is going. Plus into your gearbox and diff, wheel bearings, tyres. There are losses everywhere.
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    (Original post by CurlyBen)
    There's two issues here: firstly, what is meant by efficiency, and secondly what you're measuring the efficiency of.

    Efficiency is defined as the ratio of useful energy you get out of a device to energy you put in. As gbduo's already said that's a problem with engines as they tend to waste a lot of energy as heat. As a rule of thumb efficiency tends to increase with displacement as the surface area to volume ratio decreases and piston velocity decreases. That probably sounds counter-intuitive as efficiency with cars is normally taken as how far will a certain amount of fuel get you, which brings in a whole range of other factors, such as weight, driving style, terrain, auxiliaries etc.
    The big problem is that heat generation isn't an unwanted byproduct of the process, as it is with a transformer, but it's integral to how the process functions. The only way to get a proper step change in efficiency is to devise a process that can extract energy from a potential energy source without converting to heat first. Hydro electric is one method, and I believe hydrogen fuel cells are another - the problem is obtaining the potential energy, which in both cases generally relies on a conventional, heat generating power source.

    Secondly, your power supply example isn't really comparable to a car. It's just one component in a chain - to make any kind of meaningful comparison you'd have to start at the prime mover (the power station) and factor in transmission losses etc. right through to your output - and I'm not sure how you would quantify the useful power output of a computer. When you factor all that in the whole system may well be down to the 30% efficiency bracket. Your power supply comparison would be better applied to a gearbox or differential, where you could well be seeing 90% or so efficiency.

    And if you think it's so shocking that engines waste so much energy as heat, big engines in low speed applications might be using 10% of their useful output running a fan to get rid of the excess heat!
    Hmm thanks for that. Makes sense somewhat I guess. I was using a PSU as a comparison because I thought of it as the thing that actually powers a computer, and an engine being the thing that actually powers a car

    And maybe Im shocked because I'm an IT guy and pretty much every thing is pretty damn efficient
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    You can buy the older style Prius on auto trader for about 3 grand....


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