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None of the hybrids gets anywhere near the EC test figures on the road unless hypermiled. Not that these figures are meant to do be a realistic represnetation of what you get - how could they be? They're just for comparison. But, with hybrids, the current test methods do not specify how the battery set is charged and discharged, SFAIK. The tests are carried out by the makers. Given that the Prius battery set is controlled to maintain charge no greater than 80% full capacity, and no less than 40% discharged, there is scope for creative mpg figures by running a fully charged battery set until discharged. Hence the nonsensical Lexus figures of 40mpg plus, when they seem to get <30 mpg in actuality. Caveat emptor.
Edited by nortones2 on 23/01/2011 at 19:47
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The Prius drive-train in the Auris Hybrid does even better - 89g/km CO2 and 74.3mpg.
Although the Golf SE BlueMotion Technology 1.6 TDI 5dr Auto does 109g/km CO2 and 67mpg, or without the autobox 99g/km CO2 and 74mpg
Edited by colinh on 23/01/2011 at 20:36
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"none of them exactly eclipses the consumption and CO2 figures of their conventional petrol or diesel rivals."
Toyota Prius urban figure 70.6mpg
Let me know which petrol/diesel family sized automatic does close to this and I'll have one.
The real world figures for the Prius are a long way from the quoted ones. I averaged 28mpg in a Lexus RX400h and 45mpg is more typical for the Prius.
That said, around town they make some sense, but there are plenty of diesel cars that are more efficient on a longer run where the hybrid system is just a dead weight.
Steven Quas , Hamburg
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So these models should do the 10 mile commute each way without the engine starting up - as long as you remember to plug the car in at night!
How much does that actually cost? If I charged an electric car every night in that way, what would be the end result on my electricity bill?
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If you read the February edition of What Car magazine , they have an interesting article on the cost's of The Nissan Leaf (electric) Vs Toyota Auris(Hybrid) Vs VW Golf 1.6 TDI Bluemotion (Diesel). They include purchase price,Tax, servicing, fuel (including re charging the electric) etc. Overall the Golf was the cheapest to run due to the high cost of the electric car. Worth a read.
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Another thing to consider is cars such as the Toyota Prius are proving very reliable but the latest diesels with DPFs are having problems (expensive dealer regen or even more expensive Particulate Filter replacement etc...). A Friend of mine who lives out in the country is getting a real life 60mpg out of a Prius+
HOWEVER my issue with the Prius is that the engine/motor all runs through the CTV gearbox. The Ampera looks interesting as I believe it will be directly driven by wheel hub electric motors with no energy sapping gearbox. Electric motors can have high tourque from 0 rpm through to high revs - You can use fancy driving electronics to achieve this rather than a gearbox.
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"After the Volt battery is depleted, it switches to extended range mode, when a small 4-cylinder internal combustion engine burns premium gasoline to power a 55 kW (74 hp) generator supplying the electrical power to extend the Volt's range. In addition, while in extended range mode and travelling at highway speeds, the engine can engage mechanically via a clutch to combine with the electric motors for propulsion."
"EPA rated the Volt's combined city/highway fuel economy at 93 miles per gallon gasoline equivalent in all-electric mode, and at 37 mpg-US (6.4 L/100 km; 44 mpg-imp) in gasoline-only mode, for an overall fuel economy rating of 60 mpg-US (3.9 L/100 km; 72 mpg-imp) combined."
i.e., approx. same as the Auris
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Of course the combined MPG would very much depend on how often the petrol engine was called into service. If the daily mileage is within the battery range, all this would be done at the 93 mpg petrol equivalent.
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Re Big John's concern. Prius has a transmission, but no gearbox. Its called a power split device which has nothing at all to do with the CVT designs. Probably not as efficient as an electric motor at each wheel, but that brings other issues with it. Here's a description of the PSD - eahart.com/prius/psd/
Edited by nortones2 on 25/01/2011 at 14:36
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The Ampera looks interesting as I believe it will be directly driven by wheel hub electric motors with no energy sapping gearbox. Electric motors can have high tourque from 0 rpm through to high revs - You can use fancy driving electronics to achieve this rather than a gearbox.
The Ampera/Volt doesn't have wheel motors, it has a very interesting powertrain.
AIUI the engine primarily drives a generator, and the motor primarily the wheels. However, there is a planetary gear and some clutches that connect it all up, allowing the elec motor access to a couple of different ratios, but importantly for the petrol engine to also provide some torque to the wheels during (I think) high speed cruising. It is quite innovative and GM were very coy about it, but there are explanations of how it works if you search in Google. I'm certainly not going to try and explain it all.
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The critical bit about cars like the Leaf, when the technology is expensive and probably a long way from being optimised is that the economic case is pretty weak, so the purely rational purchaser has to think about it a bit.
Basically I reckon it will suit long-distance commuters that typically travel maybe 50 miles a day. Not enough miles and you don't get the benefit of the reduced fuel cost. Too many and you'll be driving in brown trousers (and thick sweaters in winter). Obviously that is contingent upon there being charging points at each end, which is beginning to happen (know they are in Leicester/High Cross and Bham/Bull Ring for instance).
I haven't read the What Car article, but the thing that I would hope to see there is a sensitivity analysis on annual mileage - it would be interesting to see where the break-even point of Leaf vs Bluemotion is. The key point is here is that (comparatively) the Leaf is expensive to buy/cheap to run, whilst the Golf is cheap to buy/expensive to run. Hence you need to "sweat the asset" to make it worth the money.
Another thing to note is that it's worth changing to an E7 tariff if you will be charging an electric car (but take note of when your cheap rate starts/ends to maximise usage, and put your dishwasher etc on a timer too), but your "day rate" will be a bit higher than if you're on the cheapest single-rate tariff.
Of course, all of the above assumes an entirely (economically) rational purchaser. But spend more than 10 seconds browsing this kind of forum and you'll find out that people aren't rational in that way, otherwise the world would be much duller as we'd all drive Hyundais, and Alfa Romeo would be long dead.
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Okay, let's guess the car's efficiency is around 30kWh/100km. A bit of research shows low 20-something for GM EV1 or BMW Mini-E, but lets round up a bit for real life. That is charging efficiency, so it reflects the power you're feeding in from the mains.
A 10 miles round trip is 32km - roughly a third of a 100km, so it'll be 10kWh for your daily commute.
So then it's just a question of finding a suitable electricity tariff. It would be sensible to use Economy 7 and charge at night. (A standard mains socket can supply 3kW, so no reason your daily charge should take much more than 3 hours, even if you don't have a special high-current charging port).
A quick web search suggests night-time rates are below 6p/kWh. So that's under 60p per day.
Someone else can do the sums for petrol - but it would certainly be at least a couple of pounds per day.
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Yeah, it's much cheaper because domestic fuel isn't taxed (ok, there's VAT at 5% but compared to fuel duty, that's negligible). But electricity isn't fuel, it's an energy carrier. Where does electricity come from? In this country, over 3/4 of electricity is generated from fossil fuels-so an 'electric' car is getting a tax free ride (and generous state subsidies) just because it uses fossil fuels indirectly!
Still, it will fit in well with our incoherent energy strategy. Tax petrol at the same rate as diesel, even though a gallon of diesel is heavier and contains more carbon. Have even more generous tax breaks for LPG (even though it's barely any more carbon efficient than gasoline or diesel. Have no tax on aviation fuel at all. Give subsidies to the over 65s to spend on winter [fossil] fuel and encourage rainforest destruction in Indonesia to produce eco friendly bio fuels. Still, incandenescent light bulbs are now banned, so we're sorted, right?
This is what happens when we let arts gratuates decide energy policy...
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Yeah, it's much cheaper because domestic fuel isn't taxed (ok, there's VAT at 5% but compared to fuel duty, that's negligible). But electricity isn't fuel, it's an energy carrier. Where does electricity come from? In this country, over 3/4 of electricity is generated from fossil fuels-so an 'electric' car is getting a tax free ride (and generous state subsidies) just because it uses fossil fuels indirectly! Still, it will fit in well with our incoherent energy strategy. Tax petrol at the same rate as diesel, even though a gallon of diesel is heavier and contains more carbon. Have even more generous tax breaks for LPG (even though it's barely any more carbon efficient than gasoline or diesel. Have no tax on aviation fuel at all. Give subsidies to the over 65s to spend on winter [fossil] fuel and encourage rainforest destruction in Indonesia to produce eco friendly bio fuels. Still, incandenescent light bulbs are now banned, so we're sorted, right? This is what happens when we let arts gratuates decide energy policy...
Agree with most of that, except "incoherent energy policy". I am not aware that we've really had an energy policy at all? :-) Would point out that as EVs take off, the fossil fuel mix on the grid should steadily decline. I would also say that the differential taxation can be justified to achieve the policy ambitions of low carbon and energy security. Luckily this "more electric" future means you get one by doing the other.
Civil servants and their political masters are also completely incapable of seeing the "whole system" picture of energy flows (and the associated cash flows) - the massive subsidies for solar panels on roofs are being paid for by a levy on suppliers, which increases all their costs equally, hence people struggling to pay their gas bills this winter are paying more to subsidise investors in solar. Only saving grace at the moment is that there aren't enough systems installed to meaningfully impact our bills yet.
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How will EVs cause a decline in fossil fuel mix? You're simply swapping direct fossil fuel emissions for indirect ones. Pump sales decline but grid use increases-and we've got a shortage of grid supply as it stands. The well-to-wheel efficiency of an electric car isn't greatly superior to that of a good diesel/petrol car.
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You ignore the fact that swapping petrol for grid supplied electric means that valuable oil is not wasted by burning it away. That oil is needed for other things such as plastics, medicines etc. It could also mean that a country is less held to ransom by OPEC.
Switching to electricity also opens up other possibilities such as hydro, solar and wind generated sources. If you live in Canada for example, most electricity comes from Hydro.
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The vast majority of our electricity comes from fossil fuels-and the proportion is rising, not falling. Hydro, solar, and wind are a bit of a joke in this country and that isn't going to change soon. We haven't got the space or the head of water that Norway and Canada do. Electric cars would be great if we had an abundance of electricity. As it is we have a deficit (another one!). Until we sort out our electricity generation, electric cars are a tax-dodging distraction that we can do without. It's like the 'hydrogen economy' fallacy. Once you factor in the thermodynamic cost of producing the hydrogen, and combine it with the inconvenience of storing it, you realise that one has gone in a big circle and wasted energy in the process.
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Yes, obviously, fossil fuels are used to generate electricity. You may view Hydro, solar etc. as a joke, but increasing use of them is going to be necessary - fossil fuels aren't going to last forever. Switching to electric and electric hybrid vehciles is all part of the process that the world needs to go through to decrease the dependencies on fossil fuels. Decentralisation of electricity generation to your house, is another way in which efficiency can be increased, and this will only help to make an electric car cleaner.
Solar panels will get more efficient, wind generation will get more efficient: Throwing your hands up in the air and saying 'we aren't there yet' and 'it is a joke' is no reason to stop the progress that needs to be made towards removing dependency on finite fossil fuels. I disagree that Hybrids are a distraction - their Co2 output is relatively low are their economy is excellent - these are good things, that need to be encouraged.
I agree that Hydrogen is a dead end.
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Wind power has a major problem.. It does not work in cold frosty weather. Period...
And capacaity utilisation over the years from 2007 to 21010 is under 28%.. So we need to install nearly 4 times the capcity actually needed to at peak requirements to meet the peak : but have 100% backup for when it does not work.
And 100% backup is either nuclear or fossil..
Only a fool would plan on that basis. We have...
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And what happens when that backup fossil fuel runs out? Do we say "oh dear, we spent the last 50 years ignoring the problem and we have no viable mature, sustainable, developed alternative"? Not a good place to be in. Fossil fuels are not the future. The problem isn't going to go away by saying the present alternatives aren't good enough.
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I think your comment on wind power may possibly a little dated: www.renewable-energy-sources.com/2009/11/09/ge-2-5.../
"According to the Canadian Wind Energy Association (CanWEA), Canada surpassed 2,000 megawatts of installed wind power capacity last year and is expected to exceed 3,000 megawatts in 2009. Wind currently supplies about one percent of Canada’s electricity demand, with the country’s wind turbines representing more than 2,800 megawatts of generating capacity, enough power to meet the needs of more than 860,000 homes. The province of Ontario is currently Canada’s wind leader with 1,162 megawatts of installed capacity, providing clean electricity for over 300,000 homes.
GE currently has a strong wind presence in Canada, with an installed base of 938 MW (39 percent) nationwide and 780 MW in Ontario (62 percent). GE is also a lead supporter of CanWEA’s “WindVision 2025” initiative to work with federal and provincial stakeholders to provide 20 percent of Canada’s electricity with wind power by 2025, resulting in an estimated 52,000 new “green collar” jobs and $79 billion in new investment nationwide.
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Edited by bodgerx on 26/01/2011 at 12:26
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Wind currently supplies about one percent of Canada’s electricity demand,
Virtually Negligible-and Canada has the advantage of a great deal of space. All the rest is aspirational guff. We all want clean, sustainable, affordable power-but that in itself isn't a policy, it's an aspiration. Denmark can only manage to have such a large proportion of its electricity generated by wind because it relies on other countries' base load (gas and nulcear) which, frankly isn't responsible or sustainable-it's a typical 'emissions elsewhere' fudge. Nasty, profit grabbing, dirty, electricity companies have huge cash reserves and a wealth of engineering expertise. ALL of the 'eco' sources of electricity currently on offer have been carefully analysed by expert engineers and have ALL been found to have significant shortcomings. If you think you can do better, good luck to you.
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1% is a start. I don't think I can do better - I'm not an energy engineer. The fact is there will be no choice in the future if fossil fuels disappear.
Decentralising energy generation is also a positive step in the right direction - the amount of inefficiency and loss from generating power centrally and distributing can not be the future.
You may call all this aspirational guff - but this is the future. The alternative is no power, or 100% nuclear.
Yes, every source of energy generation has its short comings - fossil fuel burning has a major one: there is only so much of it and then it's not coming back. Doesn't get anymore show-stopping than that.
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Well, I am an energy engineer (HD diesel), and on current performance, 'eco' alternatives look very poor once you strip away government sponsered externalities (tax/subsidies etc). There is no shortage of fossil fuels, just a shortage of clean, conveniently situated resouces. Coal and oil shale resouces are very plentiful. Of course the extraction, envirnonmental and processing costs are greater-but there is no hydrocarbon armageddon looming. They key thing is to decide whether CO2 emissions are the problem, or fuel resouces are the problem. If the it's the former then we indeed have a problem, if it's the latter, it's a paper tiger.
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Plentiful but not infinitely lasting. There is a key difference.
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My comment on wind pwer in winter is not dated.
On frosty cold days, there is little wind. Period.
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I think you may need to do a little research - the cold per-se isn't necessarily an issue. You said it isn't possible period. I don't think that is the case.
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45 mpg is pretty poor for a Prius Gen 2. Most people will average mid-50's or more without trying. 60+ is achievable with some basic technique.
Gen 3 Prius is capable of even more.
I get 54mpg in my Gen 1 Honda Civic IMA and it is rated at 57 I think. To say that these Hybrids are a long way off on the official figures is a little unfair - considering how the same should be true for other cars.
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For what it is worth, my Gen 2 Prius over 35,000 km of accurate fuel and distance recording [ including odometer correction ] has reurned 4.48 l/100 km average under all types of New Zealand driving. I do a reasonable proportion of long-haul driving including a fair bit fully loaded, so I am satisfied that it does what it says on the tin. Speed limit here is 100 km/hr, which is where I set the cruise control [traffic permitting], so nobody can accuse me of being a doddering petrol-miser. { Others more mathematically-minded can do the conversions.}
In Europe I drove a new Pug 307 station wagon 1.6 diesel over about 7000 km in France, Italy, and Switzerland. That returned 4.3 l/100 km on my driving style. All types of road, and over passes rather than through tunnels. 140 km/hr by GPS on the autostradae.
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I suspect Honda are more pessimistic in deriving their test figures, otherwise they would have less "disappointing" numbers for the CRZ .
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