Bishop Hill Why electric cars are really coal cars
Apr 6, 2011 Energy An interesting look at arguments for electric cars by a Professor of Chemistry:
It is claimed in a Royal Academy of Engineering (RAE) report on electric cars that they are in any case cleaner because 80 - 90% of the energy put into them in terms of electricity is recovered in terms of useful power at the wheels, to be compared with 20 - 30% in a conventional oil-powered car. Well, that sounds good, but the reality is that only about one third of the energy in the coal or gas actually ends-up as electricity because of the Second Law of Thermodynamics and the Carnot Cycle limit - the other two thirds being thrown away as heat. Thus the electric car is harvesting in terms of well-to-wheel miles only about 27% of the original fossil fuel energy, so not that much better than the standard car running on petrol or diesel. The difference is merely whether about the same quantity of waste heat energy is thrown away at source or in the vehicle.
Reader Comments (63)
Have the transmission losses from generator to user been accounted for?
Lord B beat me to it - but also what about issues around dealing with batteries once they die, with the associated need to produce new ones. I dont know how long they last, but I am sure it will be significantly less than the lifetime of a typical car!
Well, to be fair, there is at least a possibility that the heat from generating the electricity can be used rather than thrown away. The heat created by a petrol/diesel car is pretty well all thrown away. However, with with CHP schemes, it is possible to do useful things with the heat from generating electricity, such as heating homes and other buildings, or supplying glasshouses, etc. Of course, at present, very little of this is done, so the negative view of electric cars is fair.
The heat created by a petrol/diesel car is pretty well all thrown away.
Not all, was very warm and toasty driving home late last night, electric coal cars range is limited even more in cold weather due to no spare heat being available.
It also generates UHI which is used (ok ignored) by CRU to support AGW.
Why is it that I feel I should expect more from a professional body than this? especially when its title includes the word "Royal".
True, for a given value of truth. It used to be that companies such as Arthur Guinness, when they were at Park Royal, purchased large quantities of coal for combustion on chain grate fired boilers . The high pressure steam raised was first used to generate electricity, some of which was sold under contract to the National Grid. Then the steam was used for process; brewing their stout. Finally the steam was used for space heating and only then released to atmosphere. The thermal efficiency was in the region of 85%. I know this because I used to work for the National Coal Board in the time of Robens.
District heating systems, grouped around power stations were big business in the 1960s. Waste heat from Battersea power station used to be sold to Dolphin Square. Greenhouses for tomato growing etc., are profitable when supplied with heat and CO2. As for transmission losses, it made economic sense to send coal 100 miles by rail than to generate electricity and send it down the wires. That was the case 50 years ago, but post modern economists ignore rationality and cook the books.
It might surprise you and your readers to know that over thirty years ago HMG made a serious, and seriously underfunded, attempt to develop electric car technology. I worked on it and wrote about for TAV just before Climategate and indeed the current hooha about electrics Here:
http://noconsensus.wordpress.com/2009/11/13/electric-cars/
Kindest Regards
Re: Mike Edwards
I remember seeing a program, a few decades ago, where they cooked their evening meal using the heat from the engine generated whilst driving home from work.
Yes I know its a ridiculous idea but it was fun watching the presenter eat half cooked, fume soaked food and saying "Hmm, lovely." without a single grimace.
If there was a battery which could store 100x the charge per unit volume of present devices, then electric cars would be viable (you wouldn't need those charging stations -- just slot in a new battery every few months and take the old one to be recharged.)
30 years ago, Arther C Clarke said that such an invention was overdue, but we still haven't made much progress in that direction.
Perhaps we should redirect all that money wasted on global warming research on something like this which would have measurable environmental benefits.
Rick Bradford, improved battery technologies are being pursued very hard for a wide range of obvious reasons. It's a tough problem.
But if you generated the electricity from nuclear (or wind!) . . .
I bet those who drive cars rather like it during 6 months of the year when the engine warms up and they can heat the interior of the car, and demist their windows, so some of this 'waste heat' is of considerable use. Sure, if I had an electric car I could run a heater directly from the battery and get heat faster, but then that's just consuming additional energy.
It's true - only about 33% of the energy from coal or gas ends up as electrical energy at the power station itself: thermodynamic principles at work.
Don't forget about the losses in electrical power transmission to everybody's homes (5-10%) and the losses in charging and discharging the battery (chemical energy), and the additional loss in converting to motive power.
The true figure for the electric car is under 22% when all the losses are taken into account (and worse again if you have to run an electric heater to keep warm in winter), making the electric car worse than a modern internal combustion engine. But that still doesn't tell the full story because the electric car is so much heavier, so driving losses are higher. Currently, the amount of fossil fuels consumed to drive 100 miles in an electric car are higher than they are in a diesel car. No contest.
But this comes as no great surprise. If you start with fossil fuel and want to power vehicles, so long as you try to keep everything as efficient as possible you are always going to end up somewhere in the 20-30% range for overall efficiency based on inviolable principles of thermodynamics.
Factor in everything else: range, weight, charge/fueling time, and electric cars are not very practical. Their main use perhaps is as a second car for those who can afford such conspicuous consumption and waste of the earth's resources, their main car being a fossil fuel car.
Another reason why electric cars are coal cars.
"Wind farm efficiency queried by John Muir Trust study"
http://www.bbc.co.uk/news/uk-scotland-12985410
"Analysis of UK Wind Power Generation November 2008 to December 2010"
http://www.jmt.org/news.asp?s=2&nid=JMT-N10561
Those figures are damning.
I'm sure it is a tough problem -- maybe the Tobacco mosaic virus will help.
It just seems to me, as it seems with fusion power, that progress is not as dramatic as with some other difficult technologies which were made serious priorities (the Manhattan Project, for instance).
Incidentally, I sometimes wonder whether the hard Green movement would welcome either development -- clean available fusion energy and a way to store all that energy in a convenient and portable way.
Wake me up if the MSM get hold of the story. I'd just love to see the faces of all the CAGW alarmists when they open their morning papers and realise they have been killing the planet by running their Toyota Pious.
FarleyR, The Toyota Pious is a different beast - you'd don't charge it up from the mains - it powers up its own batteries from its engine. Still, as we discussed here a few weeks ago (on this thread - yes it has a different title and the post is unrelated, the Prius is less efficient in terms of miles per gallon than a Beemer. That was based on an albeit not-so-scientific test as reported in the Times, which lapogus linked to from that thread.
Lordy, next thing they'll be telling us plastic bags are better for the environment than paper bags! [oh yes, so they have!]
A 'carbon accounting' company on my patch has produced a report which shows electric cars as producing 75g/km emissions (upstream electricity generation). That compares with a vaunted 105g/km for the new Kia Picanto.
Report: http://www.ecometrica.co.uk/ecometrica-press/technical-papers/your-electric-vehicle-emits-75-gco2km-at-the-power-station-2
Background detail: http://cameronrose.blogspot.com/2011/03/measuring-emissions-from-green-cars.html
O/T
Rees has won the Templeton prize... says it all really... fits him perfectly, glad he has, shows him for what he is...
Guardian: Martin Rees wins controversial £1m Templeton prize
Mac - don't forget the number of lovely blocking anticyclones which were (and are regularly) a feature of the winter of 2010 - when the output from windfarms reached a massive 0.1% of demand (not sure how this relates to capacity)... The BBC seems to have forgotten those - but then they would, wouldn't they..??
Re electric cars - surely we all knew that they are really coal cars - its only the government (DECC and DoT in particular) who don't..?
They really do think we're stupid, don't they..?
I note some pertinent comments about the severe limitations of batteries above. The lack of progress here is indicative of physical and chemical constraints that may not ever be overcome.
So for now we have lithium ion. One never hears about the ecological impacts of ramping up to mega-unit production worldwide of giant LiION batteries.
Nor one word about sustainable safe disposal of same once their <5yr charging life is over.
And what if we consider the energy budget (and emissions budget) for battery production, transport to point of sale, and ultimate disposal?
I wager the picture looks even worse then.
I have always seen electric cars as little short of sheer desperation. They are anything but green.
Reminds me of the saying from a few years back, when California was at the height of its eco-enthusiasm...
'What's the definition of a zero-emissions vehicle in California..?'
'An electric car for which the power is generated in Nevada..'
@John of Enfield
Why is it that I feel I should expect more from a professional body than this? especially when its title includes the word "Royal".
Which answer would you prefer:
(a) Because 'Royal' denotes a seal of approval from a meritorious institute which is fully intellectually equipped to decide which bodies do most to further humanity.
(b) Because 'Royal' is a warning that the holders and distributors of this vapid title are offspring of plundering despots who dispossessed the population of their rightful lands for their own personal greed, and then forced the dispossessed to become 'subjects' of said thieves (or offspring thereof) in perpetuity?
And then further parasitise said 'subjects' through 'civil lists' and seeking homage through dirge-time worship songs. Bargain, eh?
Your call, don't let me lead you :-)
@ FarleyR
I'd just love to see the faces of all the CAGW alarmists when they open their morning papers and realise they have been killing the planet by running their Toyota Pious.
They will simply deny it.
@ Rick
I sometimes wonder whether the hard Green movement would welcome either development -- clean available fusion energy and a way to store all that energy in a convenient and portable way.
Interesting point. I think the green demand for an infinite supply of energy with minimal to zero environmental impact is an intentionally impossible demand which they confidently expect will never be met, and therefore western civilisation will just have to shut down instead.
It's analogous to creationists constantly demanding evidence of a transitional lifeform in the fossil record. When you present them with something which patently is half-bird, half-dinosaur, such as Archaeopteryx, they simply demand fossil evidence of something that is halfway between Archaeopteryx itself and birds (or dinosaurs). The question is not honestly asked, because if an answer is provided, the question will be changed.
An environmental movement is worthwhile in theory, but the one we actually have has painted itself into a corner of abject irrelevance. Having opposed coal because of smog, nuclear because of supposed radiation risk, and now gas because of CAGW, they now in effect oppose a proper energy supply per se. They can't come out and say this, and this is why they bang on about wind and whatnot.
Cameron Rose "A 'carbon accounting' company on my patch has produced a report which shows electric cars as producing 75g/km emissions (upstream electricity generation). That compares with a vaunted 105g/km for the new Kia Picanto."
Well, now, our company runs a VW Golf diesel which does under 100g/km by official figures. Of course, it's really, really easy to measure the CO2 per km with a petrol or diesel car since it comes out the exhaust pipe, and is a piece of cake to calculate to high accuracy by weighing the amount of fuel used from the fuel tank and multiplying by a simple factor.
And it's really, really easy for someone trying to sell electric cars to fiddle the numbers because there is no such measurement on CO2 that can be done on the car itself, either by measuring direct emissions or weighing anything. So there will be all sorts of assumptions and inferences and, you can be sure, all sorts of inefficiencies conveniently forgotten about to work up a number for the CO2 produced at the power station to make it better than it really is.
The truth of the matter is that the conversion from fossil fuel to electricity is only 33% or so at the power station. Adding transmission losses, charging and discharge losses, and losses in converting the electricity to motive power you end up in 22% territory or so, which is worse than a modern diesel car. Claims that electric cars produce less CO2 than diesel cars of similar size are therefore bunk, but it's easy to see how they could bend the truth as I described above, and the reason they might want to do so should be obvious.
I guess we can go back to horses and carriages -- but then we will be pumping methane, a much stronger green house gas into the air.
Cameron
You should also remember to include the greater embedded carbon in an electric vehicle which requires rare earth metals for its Chinese built electric motor and huge, relatively short life time, batteries to store its charge.
Ed
From the paper you link to Cameron.
"A well-to-wheels analysis can be taken further still by asking about the relative emissions associated with manufacturing a traditional combustion engine car versus an electric car and its batteries. We won’t answer that very complex and detailed question with figures here but suffice to say that based on our experience the embodied emissions of the materials used in manufacture of a vehicle tend to be 15% to 20% of a vehicle’s “lifetime” emissions, when all the emissions associated with fuelling the car throughout its life are taken into consideration. The key point is that, at least on a CO2 basis, the main impact a vehicle has in its lifetime is in the consumption of energy when it’s being driven."
The 15 -20% referred to here may be true for a conventional car but is essentially unknown for an electric car because they are still an emergent technology. I suspect that the motor and battery will remain a relatively big source of embedded carbon! For a start the battery needs replaced fairly regularly but engines don't.
@EddieO,
"You should also remember to include the greater embedded carbon in an electric vehicle which requires rare earth metals for its Chinese built electric motor and huge, relatively short life time, batteries to store its charge."
Agreed. My contribution was only about emissions and, er (see the link) price.
Kia Picanto: About £8k
Nissan Leaf: About £31k
While I am skeptical of the claimed advantages of electric cars versus gasoline or diesel, one advantage shared by electric and hybrid cars is the ability to make use of the braking energy, especially in urban driving. I suspect that there are some transportation uses where a diesel/electric hybrid would be quite competitve.
"Re electric cars - surely we all knew that they are really coal cars": well of course we do, but if we fear very high prices for transport fuels, that may be reasonable. So someone might care to compare coal-> electric cars with coal->diesel/petrol cars. Fischer-Tropsch will have a few inefficiencies too.
At about the time that 'Climategate' broke, a wealthy friend in NZ who had not thought much about CAGW one way or the other was persuaded to purchase a used Prius for sales staff at one of his businesses. His accountant (a convinced Green) did the persauding, but when the Prius's battery needed replacing for more than the purchase price of the used Prius after only a few months of service, the penny dropped for my friend. He not only got rid of the Prius, he got rid of the accountant when he found that, with everything considered, the Prius had proved far less cost-eficient than the Toyota Prado, a luxurious 7-seat 4x4, which my friend used at that time as his personal and business transport.
Made suspicious by the experience with the Prius, he began to investigate CAGW at that point and it took him only a few months to arrive at the conclusion that it seemed little more than 'hysterical scaremongering'.
He is a shrewd and hardheaded businessman with considerable investments in farming. I asked him why he had made such a firm decision about CAGW in such a short time and he replied that it was easy in terms of normal 'due diligence' one would apply to any business proposition - 'no whorthwhile, concrete evidence to support the alleged facts'.
Just remember, even though the coal plant has a limited efficiency, it's also a very highly tuned efficiency, whereas the IC engine, having to operate over a vast range of throttle settings, isn't. One source says that of the energy present in the fuel, only 21% of it goes to moving the vehicle
http://mb-soft.com/public2/engine.html
That's already lower than the overall efficiency of the electric car including the power generation! Does anyone know the efficiency of the petroleum distillation process? How much energy does it take to make a gallon of gasoline? If it's on par with the efficiency of the coal power plant (which wouldn't surprise me at all), then you'll have to reduce the efficiency of the IC engine even further!
And if, as some propose, we go to solar or nuclear or wind, then there's no effect whatsoever on the transportation system. By divorcing the liquid fuel from the system, where the electricity comes from no longer matters.
Going to electric vehicles is a smart move from an energy efficiency standpoint. To say otherwise shows a lack of understanding in the systems involved.
http://blogs.forbes.com/warrenmeyer/2010/11/24/the-epas-electric-vehicle-mileage-fraud/
Dean_1230, you are right that if we start to get all our electricity from solar or nuclear (or, unlikely in my book, wind) then the objections to electric cars start to change. But the original post is about the current state of affairs (plus perhaps that in the immediate future). Electric cars are not very efficient at present. Nor are hybrid cars - D Johnson points out above that they can do kinetic energy recovery. But so can conventional cars - as was pointed out in the article I linked to. The people who go on and on about how environmentally friendly electric and hybrid cars are are at best talking about future virtues - not current ones.
Just how much extra electricity generating capacity and infrastructure will we have to install if we are to switch to using electric cars on a large scale?
Are we also going to take into account the carbon/energy cost of doing this?
It would be interesting to know the number of gigawatts of generating capacity required if electric cars did all of the current car return trips under 60km.
Some decades ago, the Chairman of the Coal Board was taken to task by an interviewer because he had an electric fire in his office when he ought to have had a coal fire.
His reply was on the lines of, "Electricity is coal by wire".
plus ça change, plus c'est la même chose - as they say in Paris.
Dean_1230
Please demonstrate your level of understanding of the systems involved:
- Energy used and CO2 emitted by global-scale manufacture of Li ION battery packs?
- Energy used and CO2 emitted by global-scale disposal of Li ION battery packs?
- Environmental impact of global-scale manufacture of Li ION battery packs?
- Environmental impact of global-scale disposal of Li ION battery packs?
Thanks.
I think us skeptics are making the same mistake that the alarmists make, but in reverse, the alarmists say petrol/diesal cars bad/ electric cars good.
Patently it is better to have electric cars, buses and commercial vehicles in cities to reduce concentrated air polution and noise. Outside cities and for long journey petrol/diesel vehicle come into their own.
The arguments about efficiency should take into account that electric cars must be heavier than the equivalent capacity car driven using hydro-carbon fuel?
So in summary It's horses for courses:-)
Dean_1230
Er, no, wrong on nearly all points. "Going to electric vehicles is a smart move from an energy efficiency standpoint. To say otherwise shows a lack of understanding in the systems involved." What little you know!
Your 'source' (C.Johnson, a graduate physicist from Chicago University) states "a conventional internal combustion engine cannot have an overall efficiency of greater than around the low 30% range...the most efficient production engines are around 25% and most vehicles on the highways now have engines which have around 21% overall efficiency."
So, compare on an like-for-like basis. You can't compare a brand new electric car with 'most vehicles on the highways', which obviously includes older cars. So compare the best production electric cars with the best current production petrol/diesel cars, and try to be a bit more objective.
The other thing is that petrol and diesel car efficiency is increasing all the time. It will never get beyond 30% efficiency using conventional piston engines, but there is still some way to go (37% is the theoretical limit). And we can expect internal combustion improvements will take this up to 60% or so using different types of IC engines e.g. Wave Disk http://www.newscientist.com/article/mg20928035.100-shock-wave-puts-hybrid-engines-in-a-spin.html
On the other hand, electric cars can't get much more efficient than today's 22% because of generator efficiency (around 33% for fossil fuel power stations with steam turbines) and distribution losses, and the basic resistance of copper wire, which I don't think anyone is going to improve on in the near future, since they won't be switching to silver wire. Perhaps after many years the best electric vehicles might attain 25% where the technology will flatline, but latest internal combustion engines are already better than electric and will continue to improve way beyond 25% efficiency.
@ Dean 1230
Does anyone know the efficiency of the petroleum distillation process? How much energy does it take to make a gallon of gasoline?
Depends how you define it.
Refineries burn fuel oil to provide the heat for the various processes. How much they burn depends on how many units there are, but a fag-packet estimate for a modern deep conversion refinery would be about 6% (the technical term for this is "own use and loss", or "fuel and loss", or some portmanteau term of both).
The price a tonne of fuel oil was $648.50 yesterday, per Platts European Marketwire. A 10 million tonne (75 million barrels) a year refinery (about the European average size) thus consumes annually 600,000 tonnes of fuel oil worth $389million. From this it produces 75 million barrels of various products, so the cost in fuel to produce one tonne of refined product is about $5.20 a barrel.
Put another way, 94% of the crude that goes into a refinery comes out as a usable product.
You could argue that there's a further cost involved in building the refinery and supplying it. Refineries are expected to last 30 years and one such as described would cost about $2 billion to build. So over its lifetime, it'll process 300 million tonnes of crude at a capex cost of about $6.70 per tonne, or $1 a barrel. No idea what the energy cost of $3 billion of EP&C is, I'm afraid, but it's obviously not going to be the whole of the $3 billion. Maybe 10% of it? Say $0.10 a barrel?
Then there is the cost of the fuel used to ship the oil to the refinery. This depends on where it's coming from but if you figure a freight cost of say $1 a barrel and assume half of that is bunkers you probably wouldn't be far wrong.
So to sum up we have:
OU&L: $5.20
Fuel used in construction: $0.10
Fuel used in supply: $0.50
Total: $5.80 per barrel.
There are generally reckoned to be about 7.9 barrels to a tonne of gasoline, and gasoline yesterday was worth $1,119 per tonne. So a barrel of gasoline is worth $141.65 a barrel and you have to spend about $5.80 in fuel to get one.
Does that help?
Hm.
I wonder - do all the electric-car-enthusiasts think for a moment that the day may well arrive where they have to decide between charging up their car or running their heating/cooking/washing/lighting, never mind TV and/or PC, given the lack of investment in power stations of whatever flavour here in GB? And especially given the various warnings we've seen recently about possible electricity rationing, without everybody running an electric car?
A fairer comparison for the electric car would be the horse & carriage: limited range, long recharge time, blankets & hot-water bottle, alternative fuel for lights and the prime mover fuel source comes directly from solar radiation while sequestering CO2. To do a comparison with the modern IC engine does the electric car a disservice.
@ simpleseekeraftertruth (Apr 6, 2011 at 6:30 PM):
"A fairer comparison for the electric car would be the horse & carriage: limited range, long recharge time, ..." - yep, but think of all the new 'green' jobs to be had when we go back to horse & carriage! Ostlers, coach-builders, wheelwrights, coachmen, grooms, stable boys ... all the muck to be mucked out and taken away ... my, wouldn't our unemployment numbers shrink ...!
;-)
One of you said something about throwing away or recycling batteries. This is a most excellent point. There is not one battery technology nor will there ever be one, that will not produce huge costly programs of disposal.
No matter how many times a battery can be recharged the number is finite. Then comes the dirty work. Oil and Coal are relatively clean fuels. A battery is a dirty piece of machinery. Don’t believe it? Take one apart.
I would suggest that we tend to prefer our cars reasonably enjoyable to drive as well as being able to get us from A to B, so the engines are generally way bigger than they need to be. As performances have improved we now have cars with moderate sized engines that give the kind of performance, certainly cruising ability, that fifty years ago would have required a large capacity and thirsty engine. Due to traffic and dawdling drivers, I rarely exceed fifty MPH on my daily commute. If my car had say a 500cc engine instead of its 1400 turbodiesel, it would be pretty depressing to drive but would get me to work in exactly the same amount of time but would use less fuel and produce fewer emissions. I'm not sure what the performance of electric cars is like nowadays but I suspect that it is not that good. How economical and polluting would a conventional car be if it only had to match the performance of an electric?
As someone who grew up in Alberta, Canada, we had the annual event around Dec 1 when a sheet of cardboard was inserted in front of the engine radiator to reduce windflow and allow the engine heat to be retained for quicker heating of the passenger compartment, allowing the engine to run a little hotter and improve performance, and reduce warm-up time when the vehicle was parked outside overnight at -30 C. For about 4 months of the year, most Canadians consider the 'waste' heat from an ICE to be a very desirable byproduct of internal combustion.
Ditto for incandescent light bulbs, those wonderful distributed heating elements that give off 'waste' visible light.
George Steiner
Re battery disposal, it was me. It never seems to feature in the 'must electrify personal transport' message. I wonder why.
Get one of these and choose to be as inefficient as you like:
http://www.autoblog.com/2011/02/21/volvo-v60-plug-in-hybrid-detailed-ahead-of-geneva-debut/
SFT:
Modern combined-cycle gas turbine generators, which are very common now, generate electricity at a 50% thermal efficiency, up from about 45% in the 1990s. These provide a large and increasing share of the electric generation in most countries. Modern coal plants and standard-cycle gas turbines are at about 40% efficiency now. Transmission losses in a small country like the UK are probably at about 5% (they are 7-8% on average in the US).
Under reasonable assumptions, you probably come out a bit ahead in "well to wheel" efficiency with electric vehicles compared to ICE vehicles -- but certainly not enough by itself to justify a complete reworking of our infrastructure.
Electric vehicles have suffered from a form of "mission creep". The original push for EVs in the 1980s and 90s, led by California, was to reduce the pollutants (real pollutants, not CO2) resulting from vehicles. "External combustion" as in electric generation, produces far lower pollution than equivalent power produced in internal combustion engines. However, the technology wasn't close to ready at that time. (It is getting closer now, but still quite a ways away.) So interest waned. Somehow it got resurrected in the battle against climate change, where it is not all that appropriate.