- This topic has 107 replies, 31 voices, and was last updated 15 years ago by coffeeking.
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Do electric cars really help?
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eckinspainFree Member
So the government are going to plough money into reducing carbon emissions and bolstering the UK economy by supporting electric vehicles.
But given that the electricity has to come from somewhere in the first place (burning coal in power stations mostly), does this actually help much?
I’m guessing it must make a difference as our government wouldn’t just support it in the hope it would be a vote-winner (oh, hang on…)
I suppose at the very least it moves pollution out of the city centres (?)
mrmoFree MemberI think the only real benefit in our situation is that it gets pollution out of city centres. If we were Switzerland or Norway where Hydro accounted for a large proportion of the total energy supply then the benefit becomes far clearer in that pollution is far lower in total.
But that involves joined up thinking…..
TandemJeremyFree MemberNo total benefit – in fact a small loss due to conversion losses – fossil fuel / elec / power rather than fossil fuel / power
richcFree Memberits also easier to make a number of more efficient power stations, than it is to try and make millions of individual little engines run with the same losses.
matt_outandaboutFull MemberGoing back to the old ‘what happens when the wind don’t blow / waves don’t rise / rivers stop flowing argument as well, many cars could be charged on a ‘Economy 7’ type tarriff – off hours and when there is more generating power in the system than demand.
Also work out that the average car journey length is just over 3 miles – persuading more people onto electric bikes / scooters / and cars would make sense and quite a saving.
I do think the market for an electric scooter would be a good one.
Also, factor in that making fewer journeys, walking and cycling more is a far more effective way of reducing emissions, energy demand, a healthier nation, a faster less congested nation etc etc…
thegreatapeFree MemberHaven’t they also come up with a new way of building the batteries, so they can be charged up very quickly? That would surely help people come round to the idea. I sometimes wonder if there’d end up being a shortage of battery ingredients but other than that I think I’d have an electric car if they were the same size as normal cars, and not too expensive.
nickcFull Member£20m of the £250m is for infrastructure. So at £5000 each, that’s what 46,000 cars subsidised, out of a driving population of at least 33,000,000…
So no, won’t really make a awful lot of difference.
davidrFull MemberIf people won’t change their attitudes to public transport then electric cars will help. As richc said, power stations are more efficient, especially if they are sited locally to conurbations and minimise transmission losses.
Have a look at a project called Better Place (that might be wrong). They use a replaceable battery pack model to remove the charging problem. It’s very interesting!
aPFree MemberWhat they should really do is charge those idiots only driving 3 miles an additional you’re too stupid tax, although what they should do about those people who drive about 400 – 500 yards to the chip shop……….
coolhandlukeFree Membermy mate gets 37mpg out of his Civic hybrid so it all sounds like a pile of crap to me. I’ll keep my diesel that does 50+mpg thanks and avoid the shame of such a car.
davey_claytonFree MemberThe main issue is that it moves power generation away from petrol and onto central generation which in theory can come from any source (though of course this is mostly fossil at the moment)
To be fair though there is a lot of energy wasted in motor car with an internal combustion engine – ie the engine is constantly on, and is often revving way above the power needed to move it about. An electric motor can make smarter use of fuel regardless of where the fuel comes from.
Someone was telling me recently about an “electric” car which has a battery charged by a 125cc petrol engine. The engine runs constantly at the optimum speed/gearing for efficiency, which means it’s never revving wildly and it’s always converting its fuel to useful power.
MrSalmonFree MemberThe power does of course still have to come from somewhere, but even with fossil fuels it’s easier to keep things cleaner at the source than in lots of engines and the source could be switched to something greener later.
The only nagging problem I have with the subsidy for electric cars is that we don’t really want to encourage people to buy new cars at all- the green benefits of running the car are cancelled out by the energy/resources used to make it and most people’s impact would be reduced by just driving the one they have now for as long as possible. OTOH if someone is going to buy a new car regardless then it’s probably better if it’s an electric one.
MrAgreeableFull MemberI do think the market for an electric scooter would be a good one.
Oh yes.
ransosFree MemberThe CO2 produced by power stations as a result of charging up an electric car is less than the CO2 that would be produced by burning petrol or diesel. I seem to recall that it’s equivalent to around 70-80g/ km which is better than any conventional car on the market. There’s also the fact that emissions are at the power station instead of the tail pipe, so a benefit for urban air quality.
However, the fundamental problem is that electric cars are only suitable for short journeys; we should be encouraging people to walk, cycle or take the bus for these. Encouraging people to use an electric car may in fact create extra mileage from private cars, which is completely counter productive.
miketuallyFree MemberI did see a calculation somewhere that showed the CO2 emissions from electric cars are about the same per km as a fairly economical petrol car. Given that there is the potential to improve the efficiency of electric cars and electricity generation, electric vehicles could be a good solution for people who really do need to drive.
What’s really needed though, is more investment in cycling, walking and public transport…
-m-Free MemberI do think the market for an electric scooter would be a good one.
These are a common site in many Chinese cities; they are styled like conventional scooters but electrically powered. Presumably there are factories churning them out at a reasonable price, so it would just take someone to start importing them, set up a dealer / service network etc.
I’ve no idea how good they are, range, charging time etc, or how long they last, but the Chinese consumer is fairly savvy – if they didn’t work there wouldn’t be many of them about.
SoloFree MemberMr Salmon. You don’t want people buying new cars ?, if so, thats pretty harsh on all those whos’ jobs rely on the motor trade. What would all those people do for a J.O.B.
Anyway, Has anyone here seen James May’s review of the Honda saloon car which runs on Hydrogen ?. In his presentation, he makes some good genaral points about car useage.
I agree, those using their car for the <3 mile journey are possibly being a bit irresponsible. But be careful, what would be the sensible minimum car useage distance ?.
I don’t like electric cars, same if not more pollution, and as someone here has pointed out, it just removes the pollution out from under out noses, the high street. To a more remote location.
Out of sight, out of mind ?.
Consider also the energy intensive production process to create an item which is seldom recycleable such as a car battery, and contains exotic and toxic materials. Then, electric cars, for me at least, seem an unattractive proposition.
What would we do with the millions of batteries we’d have when they start to lose their performance ?.Agree with another here who pointed to public transport.
I utterly hate cycling through my town centre for all the emmissions from tired old buses which kickout huge volumes of cr4p.
Perhaps local Gov should lead by example, rather than through the parking meter and clean its public transport act up first.
Running old diesel buses and telling everyone else that they’ve got to run an ultra clean car is rubbish.I want clean buses, now !.
Solo.
ransosFree MemberI’ve looked up some numbers on the web. An electric car might expect to travel 70km on a full charge – which takes 10kWh. The long-term conversion factor for the national grid is 430g CO2/ kWh. So a full charge for the electric car would emit 4300g CO2. If it travels 70km per charge then this is 61g CO2/ km. That’s comfortably better than any conventional car on the market (98g/ km for Ford Fiesta Econetic).
However, a new generation of diesel-electric hybrids is likely to hit the market soon, promising emissions as low as 80g/ km. That will be for a “proper” car meeting all safety legislation, and won’t neeed recharging. So unless there’s a significant breakthrough in battery technology, I just don’t see a future for electric cars.
BeveledEdgeFree MemberI thought the advantage was in efficiency: 20% for petrol cars compared to 95% for electric cars. Or something like that 😕
Also, more efficient to transport energy as electricity in wires than petrol in lorries to petrol stations.mrmoFree Memberit may be 95% for a car, but the efficiency of a power station brings that efficiency right down.
coffeekingFree MemberYes a power station is SLIGHTLY more efficient than a modern car engine at creating power from the fuel so gram for gram less CO2 is produced, however the problem is that your electric car has/needs:
Charging – charging is not 100% efficient, neither is discharging (losses on both directions) and to add to that this only gets worse as the car ages.
The batteries used in the cars contain some really unpleasant chemicals that need to be mined, refined and packaged into cells that have a finite life of <10 years. Most of this production is done in other countries where emissions controls are lower.
Massive investment in infrastructure is needed and really is only useable for short commutes – I think the longest range I’ve seen on a production vehicle is around 200 miles. This means I’d need a second car (and the space it takes up, extra VED, extra insurance etc) to get to other places I visit other than work.
If we switch over to electric cars instead of D/P cars we need to significantly increase the number of power stations we have. We already have a problem with not enough power stations and whether or not to use nukes etc.
Bear in mind that a new car has to be manufactured, that takes a lot of energy too. And how many people can afford a new car? Personally I could be classed as “comfortable”, I can pay my bills happily etc. I couldnt afford to buy a NEW car without some sort of finance deal which would mean me paying more in the end. Ive never bought a new car, IMO that’s just throwing money away into something that depreciates by 50% in the first couple of years.
So assuming your elec car works at ~100g/km CO2 (at the power station, long tailpipe theory) why should I pay vastly more taxes, get no rebated etc for recycling my second hand TD that manages ~110g/km?
Personally I think it’s just another giant vote-grabbing attempt with no thought behind it.
Also, more efficient to transport energy as electricity in wires than petrol in lorries to petrol stations.
Not sure that’s true – I have no figures on the fuel economy of trucks but power transmission losses over wires are vast – think in the realms of 35%.
BeveledEdgeFree MemberPower Stations are about 40% efficient, and what about nuclear, renewable etc.
WiredchopsFree MemberI agree coffeking, lets keep things exactly the same as they are now, we’re clearly doing nothing wrong.
BeveledEdgeFree MemberWhy are we having this debate anyway, hydrogen is the way forwards.
SoloFree MemberTranspoting electricity via wire. Thats some wiring there, have you seen that stuff. What does it take to produce that, transport it, lay it, maintain it, etc. Hardly cheap and clean.
Tessla produced an electric car based on the Lotus Elise. Customers had to have 3 phase fitted to their homes to charge the thing !.
And do you want a 600Kg battery behind you when you hit something….Solo.
coffeekingFree MemberWiredchops – preeching to the wrong person, I work in renewable energy research 😉
I just dont think electric cars are the way forward.
SoloFree MemberJust a thought. Has there been any research into the physical effects on the human body from being in such a close proximity to a high powered electric motor. EMFs and all that jazz ?.
Solo.
cynic-alFree MemberThey should just stop car production which must use a massive amount of energy & resources.
Cars are too cheap.
SoloFree MemberCynic-al.
Ah, a voice of someone who has nothing to lose from such a suggestion. Lets stop the industry you rely on for work. 🙄Agreeing with CoffeeKing.
Solo.
MrSalmonFree MemberYou don’t want people buying new cars ?, if so, thats pretty harsh on all those whos’ jobs rely on the motor trade. What would all those people do for a J.O.B.
That’s a good point, but I’m not sure it’s a reason to keep propping up something that is (IMO) becoming increasingly unsustainable- I’m talking about the current car-centric culture here rather than how they’re powered. And if that car-centric set up is to be replaced with something else won’t that create a lot of new jobs? I know it’s easy for me to say when it’s not my livelihood, but still, I think that in the long run keeping churning out cars to keep people in jobs might turn out to have been a bit short-sighted.
ransosFree MemberIt takes approximately 5 tonnes of CO2 to manufacture a new car. If I switched from my current car (170 g/ km) to a more efficient car (120g/ km) it would take me 21 years (!) before the CO2 costs of manufacture are offset by reduced tailpipe emissions. Whilst I only do a low mileage, even a normal mileage would take over 5 years to pay back.
ooOOooFree MemberConsider that the average car weighs 20 times more than the driver…. means that under 1% of the energy in that tank goes to propelling you if it’s just you in the car.
Thank the lord for bikes, one of the few forms of transport where the user weighs more than the vehicle.
coffeekingFree MemberIMO there is an aweful lot of waste in society. Following on from TJ’s point that we waste too much (such as household insulation etc), we waste a lot with car design too – approximately 1/3 of the fuel energy is “lost” to the cooling system and out into the environment. That energy can be harvested and fed back into the process and/or used to ease the mechanical load on the engine (thermoelectric alternators, currently being developed by BMW, not very efficient but worthy work). Braking energy recovery – vast wasteage could be recovered there fairly efficiently (as per the F1 cars) – cars at cruise take very little power/fuel, its mainly acceleration that uses fuel.
coffeekingFree Memberransos – I agree, switching to a new car isnt a clever idea (especially when you do few miles), switching to a battery powered car is even more mental – go dig up the figures for the CO2 required to create the half-ton batteries used in them!
cynic-alFree MemberSolo I’m not being entirely serious, I know it would never happen, just a bit of a shame, capitalism & consumerism and all that.
ooOOooFree MemberYou’re still hauling around over a ton of stuff with you.
If we do ‘need’ cars then I doubt they would get much more efficient than this
aPFree MemberHow many billions of pounds does traffic congestion cost us every year then?
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