Of course he was probably emitting less CO2 than I would do at that speed
> I doubt even that. A car going 85 MPH emits needs the same amount of energy as another
> car going 85 MPH (this of course ignores diffrences in aerodynamics and drivetrains though -
> but you get my gist)
LOL! Yes, most things are the same, if you ignore all the differences...
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I see quite a few Prius's being driven at speed. Let's face it, they benefit from a low BIK for car tax and can still tell their friends that they are saving the world.
Strange when you think of it, this Prius at that speed would be worse environmentally than my large S-Max that delivers an average of 46MPG.
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How so? A Prius at 85 should still manage at least 50mpg.
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And think about the huge amount of smug being produced (you will have to have seen a particular episode of South Park to understand this :)
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has it occured that the prius may have had a heart transplant with a engine that might be a little more exciting, and was the Prius doing 85 mph down a mine shaft when you saw it
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"How so? A Prius at 85 should still manage at least 50mpg."
I think those original figures were found to be optimistic and so reduced, it was in the press recenty, but I didn't pay much attention as I don't have one.
At 85MPH it's just an ordinary car carrying a weight penalty of redundant generators, batteries and motors etc....
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"has it occured that the prius may have had a heart transplant with a engine that might be a little more exciting"
There's a thought. Stuff a V6 engine into a Prius and avoid the congestion charge!
Initial reaction when I saw the Prius this morning was that the driver is probably pretty smug with his green credentials whilst doing exactly what we all do when necessity or habit takes over.
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They've already done that, pretty much - see the Lexus GS450h.
3.5-litre V6, 0-62 in 5.9s, 35.8mpg combined. And CC-exempt.
36mpg doesn't sound that great to me, but for comparison:
GS430 = 4.3-litre V8, 0-62 in 6.1s, 24.8mpg
GS300 = 3.0-litre V6, 0-62 in 7.2s, 28.8mpg
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At 85mph it's one of the most aerodynamic cars available, with an low-displacement Atkinson-cycle engine (longer expansion stroke than compression stroke) running at high efficiency. And that more efficient engine is only viable because the generators/batteries/motors.
And how heavy do you think the Prius is? Last time I compared Toyota specs, its weight was halfway between the Corolla and Avensis, which is exactly where it should be, as that's its size.
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KMO: " How so? A Prius at 85 should still manage at least 50mpg."
On what factual basis do you make that statement? Yes, it's aerodynamically efficient, yes, it had an efficient engine, but it's tilll moving a heck of a lot of air. And, once you've stopped accelerating, your mass is irrelevant.
So, where does "at least 50mpg" come from?
OK. Here goes. "A Prius at 85 should only manage a maximum of 5mpg." Just as factual.
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No chance whatsoever will a Prius do 50MPg at 85MPH.
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What does your Prius do at 85mph then?
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"What does your Prius do at 85mph then?"
Ownership of a Prius is not a prerequisite of knowing that your 50mpg figure is plucked out of thin air.
Facts, please.
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What does your Prius do at 85mph then?
That's not much of a defence really. It is a 1.5 petrol car doing 85MPH.
It might do 50MPG at 70MPH, maybe even 75MPH but not 85MPH.
Even a diesel car of its size would probably not return 50MPG at 85MPG, wind resistance is just too great at that speed.
I admit I'm going on educated guess work rather than facts but I'm sure that amongst the forum somebody will prove me right.
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We have been provided with a lot of these through our hire car provider at work. Not had one myself, but my colleague was well pleased with achieving an indicated 120 - more than his expectations, although I suspect that a hill may have been involved in the equation.
I am not sure if its my companies policy to have them, or the hire car companies (Sixt)
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I have to say that people who think a Prius is in anyway more 'environmentally friendly' than even a V8 lardwagon are either stupid or on drugs.
How much energy do you think it costs to manufacture that things batteries? How much energy will it take to recycle or dispose of them? Never mind the vehicle itself.
I can see an argument for ZEV in towns to cut down on local polllution but with cars that take their juice from something like the national grid (not the Prius) where do people imagine the electricity comes from? Jesus perhaps? It comes from stinking, polluting power stations.
In my opinion the entire drive to 'environmental friendliness' is nothing more than a confidence trick and people that buy a car like the Prius are kidding themselves for the most part.
Can see it's usefulness in avoiding the congestion charge though.
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If you go to www.greencarcongress.com/2006/05/fuel_consumptio.h...l and click on the top right graph, you'll see that at 85, a prius is returning something like 27mpg.
Interesting, and something I'd hitherto only suspected, namely that it's worse than several other mainstream cars under these conditions.
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Sorry, thats per US gallon. COmparison still relevant, but absolute figure is now 32mpg.
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The fact a Prius is less fuel effecient at speed than many 'mainstream' cars has been frequently documented in the motoring press.
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In the Times today, it said that Toyota have had to withdraw the misleading ad for the Pious (sic) that it emits up to 1 tonne of CO2 less than similar cars. This hot on the heels of having to withdraw a similar ad for the Lexus humbug hybrid about having zero guilt when driving it.
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The fuel efficiency of the Prius and other hubrids (did you see what I did there?) has become a big deal among those who pooh pooh environmentalism.
But fuel efficiency is not what it was originally conceived for. The point of a Prius is not to use tiny amounts of fuel, but to reduce smog-inducing emissions in major cities such as Los Angeles. The primary market for these things is the United States and when they first appeared very few Americans gave a thought to their gas mileage because gas was cheap. What they did care about though was being able to breathe on Wilshire Boulevard without making the linings of their lungs bleed or their eyes shrivel up to the size of pickling onions.
Now that gas is expensive the Prius's frankly pathetic fuel economy figures are being examined. But that does not detract from the fact that on short urban journeys the tailpipe emissions are much lower than a conventional car. In fact under many circumstances the Prius will add nothing at all to the filthy chemical soup that passes for air in much of Southern California.
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ruins the place where the batteries are made and disposed of though
add that to your little equation and the environmental credentials fall off a cliff face
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ruins the place where the batteries are made and disposed of though add that to your little equation and the environmental credentials fall off a cliff face
Why should Toyota care about that? They saw a market and designed a car for it. It sold pretty well and they made some money, which made the shareholders happy. Environmental bandwagonism came later and only then did the serious weaknesses of this design become an issue. If idiots buy it because they think it is "green" in a wider sense than not forcing bystanders to consume hydrocarbons, then Toyota wins again. Why should a company care if its customers are idiots as long as their money is good?
I have a suit to sell here. Yes, I know you can't see it, but hey, it looks lovely on you.
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Amazing how some people just lap up propaganda like that. Read that in the Mail on Sunday, did you? They've recently had to pull that story from their website archives, because it was a catalogue of lies and half-truths.
Some people seem to have an almost obsessive dislike of the Prius, and will seize on anything to try to make it look bad. Don't ask me why. And sometimes they just make stuff up (like the infamous CNW report that was written to show a Hummer was greener than a Prius).
Just calm down - it's only a car. It's no miraculous panacea, but it's pretty good at what it does - being an relatively low-emission, low-fuel consumption, quiet, automatic transmission family car. And as has already been pointed out - the design goal was low emissions as much as low fuel consumption.
No-one's claiming it's a super-efficient motorway cruiser. But it's not at all bad, especially for an automatic petrol car.
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I agree with KMO. The Prius is an interesting vehicle, very quiet around town and obviously quite frugal on fuel. The battery story is just a load of cobblers.
More to the point here though is the line being taken by so many people that it isn't any more environmentally friendly than a lot of other cars. That in turn underlines the fact that cars are not environmentally friendly. Do we really want to harp on about this depressing truth until we start feeling guilty and squalid like tobacco smokers?
Perhaps some of us do already. Not me though.
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I have to agree with you KMO and if people really understood Toyota's intentions when launching the car (nearly 20 years ago now as a concept) I think they could see the benefit in doing it. Toyota developed a whole new design and product introduction process that has saved them millions of $'s in that 20 years - it was not just about the car.
It also taught them about new technology.
I also see people like to jump on the environmental issue concerning the manufacture of the batteries and the supposed pollution that some newspaper printed whilst forgetting the mess an oil tanker makes when it spills into the sea/coastline and the refinery explosion in Texas (or even the war in Iraq).
It is by no means a perfect car but Toyota should be congratulated for exploring the technology and we all get the option to buy cheaper cars as a result of the manufactring process improvements they got out of the development programme.
I wonder if BMW would be doing all the re-genration stuff they do now if Toyota had not had the courage to go down this route in the first place.
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KMO: "And sometimes they just make stuff up"
What, like the fact that it'll do 50mpg at 85mph?
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> How much energy do you think it costs to manufacture that things batteries?
It takes less than you think it does. The production energy of any car is something like 15% of its total lifetime energy use. The Prius does use a bit more in production, but recoups it several times over during use.
It's no doubt less energy efficient in its lifetime that a Toyota Aygo or something of that size.
The batteries are very easily recyclable - far more so than the mass of batteries powering all your iPods and digital cameras. Toyota will pay you a couple of hundred pounds to return them.
Weird how people obsess about the batteries - about 3% of the total mass of the car, and far less toxic than the lead-acid things in their own vehicles.
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It's not exactly a 1.5-litre car; its expansion stroke is longer than its intake, so its intake is more like a normal 1.2-litre car. So it's running at a more open throttle, and hence more efficiently.
I'd agree that I probably overstated the mpg for 85mph - not least because of the over-reading speedo - it pretty much has the full 10% overread, so what I was thinking of as 85 is more like 77.
(May partially explain why Priuses seem slow...)
In my experience I'd say 55mpg at a real 70mph is possible (as long as the wind isn't against you - crosswinds hurt significantly), but it'll drop below 50mpg before you get to a real 80mph.
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Strange that magazines tests peg the Prius at high thirties mpg on motorways then isn't it?
Or are they 'making it up' as well.
I for one wouldn't deny it's a VERY interesting bit of kit, I can imagine the fun I'd have watching it's economy display (not being sarcastic) and trying to get the best out of it. What I do however find rather amazing is when people I've met who own one get all holier than though about what a great job they are doing for the environment. Quite clearly they aren't- particularly as none of them live in a city.
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You do make a good point OldHand and I think we should not create a connect with the smugness of some drivers to the efforts that Toyota are trying to make in reducing the reliance of the car on crude oil supplies.
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.....I'd agree that I probably overstated the mpg for 85mph - not least because of the over-reading speedo - it pretty much has the full 10% overread, so what I was thinking of as 85 is more like 77.........
KMO can back-pedal at an indicated 77mph, whilst using very little fuel ;-)
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KMO can back-pedal at an indicated 77mph whilst using very little fuel ;-)
That's what you're supposed to do in Priuses actually barchettaman... HJ in his test said it suited a certain driving style using lots of overrun, and he said it was frugal in medium-speed home-counties A-road conditions if I remember correctly. I imagine it would be very economical indeed - most cars are - in leisurely progress on French A-roads, 60-70 mph up hill and down dale.
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The nickel plant in Canada, which is where the Prius deniers get their fun, has been there for years. Its primary purpose is extracting and processing the nickel in yer spoons etc....Not to mention as a catalyst (Raney nickel) in margarine making and many other industrial processes.
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That's the fastest I've ever heard of, these things are normally blocking the middle lanes on motorways at sub 70MPH speeds, ...
in reply to tr7v8, see this post by vin[p]:
www.honestjohn.co.uk/forum/post/index.htm?t=50588&...f
Prius economy - Vin {P} Fri 30 Mar 07 11:50
Yesterday I was overtaken on the M3 by a brace of Priuses (Prii?)
I was making what I like to class as keen progress. They were doing a minimum of 90mph. ...... .....
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"I'd agree that I probably overstated the mpg for 85mph - not least because of the over-reading speedo - it pretty much has the full 10% overread, so what I was thinking of as 85 is more like 77."
And according to the same graph, at 77, it's be doing 33miles per US Gallon = 40mpg.
"In my experience I'd say 55mpg at a real 70mph is possible"
And at a real 70mph, they were getting 35mpgUS = 42mpg.
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That may be what that graph says, but it certainly doesn't tally with my personal experience. I've never seen anything as low as 42mpg while cruising at a (real) 70mph. 50-55mpg is typical, in still conditions.
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