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Chevy Volt Rated At 230 mpg In the City
necro81 writes "General Motors, emerging from bankruptcy, today announced that its upcoming plug-in hybrid vehicle, the Volt, will have an EPA rating of 230 mpg for city driving (about 98 km/L). The unprecedented rating, the first in triple digits, is the result of a new (draft) methodology for calculating the 'gas' mileage for vehicles that operate primarily or extensively on electricity. The Volt, due out late next year, can drive approximately 40 miles on its Li-Ion battery pack, after which a gasoline engine kicks in to provide additional electricity to charge the battery. Running off the gasoline engine yields approximately 50 mpg. Of course, the devil's in the details, because the conversion of grid-based electricity to gasoline-mileage is imprecise." Now we know the meaning of the mysterious "230" viral marketing campaign.
Chevy has been promising the Volt for years now. *IF* it ever does come out, it might be interesting - but by now their marketing campaign seems to be run by Duke Nukem.
One of many BIG questions I have: How does this thing provide heating/cooling and what impact does running these systems have on said MPG performance?
>I'm throwing the Shenanigans flag. No...scratch that...I'm throwing the COMPLETE AND UTTER BULLSHIT flag.
Have you forgotten who owns GM now? I actually think that claims now make perfect sense... they are just doing as their new bosses have done for decades.
Help Brendan pay off his student loans
I honestly don't know, but the summary would suggest otherwise. Specifically:
That strongly suggests they ARE accounting for the electricity. The question is, how? Just how "imprecise" is the conversion? I don't doubt that you are right to call BS but unraveling the BS won't be quite as simple as the objection you raised.
It is a miracle that curiosity survives formal education. - Einstein
Look at the testing yourself and see the potential loopholes. There's no reason to guess here. The information is available.
Dedicated Cthulhu Cultist since 4523 BC.
How about miles per pound of carbon dioxide emission?
Or, or in addition, miles per PRIMARY unit of energy input?
--PM
The Prius isn't plugin, so it will remain as it was.
As stated in the summary, that's the EPA's rating, not GM's rating. It comes from the same place as the MPG rating on your car right now. GM didn't calculate it, or come up with it. They are just quoting it.
And yes, it's a plug-in. (That's the point.) And that is for driving using the power from the grid. Power plants are much more efficient than the engines in cars, so I assume that's being worked into that somewhere.
That said: This is the first time the EPA has ever tried to rate a plug-in electric vehicle, and their rating system probably has a few bugs to work out...
'Sensible' is a curse word.
the devil's in the details
/. you have to actually RTFA.
... then you don't know what you're talking about ... which is how most of our politicians and most Americans operate.
aint' that the truth
For example, in politicals you have to actually RTF bill.
And on
if you don't
According to GM, I guess if I never go on longer trips, my Volt will be getting infinity miles per gallon.
Ahh, only good old GM could make a car that gets 230 mpg when it could be getting infinity mpg!
They forgot to mention the Forward Mounted, Cannon Fired Grappling Hook (TM).
The instructions were a little vauge, but the pictures showed the driver aiming on a HUD at a City Bus....so you fill in the blanks.
WTF? Over?
40 miles per day electric of your 50 mile commute leaving 10 miles to gasoline. So yeah it gets great mileage, otherwise it is like 50 to 60 max, probably lower. Too much energy loss to convert between forms of power.
the real story is, highway mileage without recharge except by the engine.
Still, lets play with numbers. Say you get your 230 mpg or more. You pay 40 grand for this privileged. Cars this size (Volt is Cruze/Cobalt size) cost around 20k normally. Lets be nice and say you optioned out well. Figure $5.00 per gallon of gas. You drive 15,000 miles a year, the Volt will burn in city mode 62 gallons, the normal car 500 ( a prius 300). $300 versus $2500 looks good. But that discounts loss of the battery, so amortize that as well. If you leave out the battery pack it still means five plus years to make up the difference IF your car only gets 30 in the city. Buy a TDI from VW and you get forty plus for around 22k.
So its hype and a bogus test meant to exaggerate the car in best possible situations. Meaning if it sticks cars will be designed to beat the test.
* Winners compare their achievements to their goals, losers compare theirs to that of others.
If you have the cheddar to drop $40k on a commuter car, you probably don't think twice about the price at the pump. Let's hope there are enough people buying this for the novelty value that it will stay afloat long enough that production efficiency can improve to the $25k/unit level.
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
Getting worse mileage than the best in the world isn't exactly something to complain loudly about... Even on the engine, it gets better than a Prius.
'Sensible' is a curse word.
Nissan said last week that its all-electric vehicle, the Leaf, which comes out in late 2010, would get 367 m.p.g., using the same E.P.A. standards. so don't worry, the volt is already 137 mpg behind the competition
Everybody seems to think I'm lazy I don't mind, I think they're crazy
I'm supposed to believe that, in 2 years of hybrid development, you've developed a production vehicle that will get almost *5 TIMES* the gas mileage of Toyota's hybrid model (that they've been developing and improving on for over 12 years)?
No, you're supposed to read the summary at the very least and understand that it's talking about an EPA-established conversion from electricity usage to equivalent gasoline consumption for EVs. Regardless of the particulars of the method, it's no surprise that this number would be much higher for something running purely off an electric motor vs. the Prius which is using its ICE most of the time even for short trips.
So if a guy drives every day back and forth to work, less than 40 miles, he's only using the plug-in electricity. But the GM exec's aren't counting that electricity he's using, only his actual gasoline used on occasional longer trips, towards the "Miles Per Gallon" rating. I guess GM thinks that people don't pay for their electricity, and that electricity doesn't come from power plants that burn fossil fuels too.
According to GM, I guess if I never go on longer trips, my Volt will be getting infinity miles per gallon.
No, Smartiac, they are counting the electricity you use. The value is only for short trips that solely use electricity. It isn't infinity because they are in fact trying to account for that electricity, but put it in terms of the standard MPG. That conversion metric has a whole host of problems with it, but it isn't ludicrous on its face. EVs are extremely efficient, and power plant electricity generation is extremely efficient compared to the ICEs in automobiles. So whatever reasonable conversion you come up with, that's probably in the ballpark.
The MPG will be much lower for longer trips because there they actually have to burn actual gas. But even that is 50mpg (again using the EPA guidelines which aren't perfect for normal cars either).
The enemies of Democracy are
In all fairness, everywhere they drove during the test was downhill.
WTF? Over?
>it has to lug around a heavy internal combustion engine
That tiny 1.0L engine that runs a generator? Id rather be able to put gas in it when I cannot find electricity, thanks. My neighborhood BP hasnt exactly switched over.
>Long range electric or efficient internal combustion. Please, please, pick one.
The battery tech isnt here. Perhaps you can wish for faeries to power the car while youre at it because youre being 100% irrational.
Hell, even if you do this, you still need to convince the gas stations to switch over, because you'll sometimes be in a situation where you need power, now, not overnight. Early adopters appreciate a little convenience.
I would just like to point out that I'm sick of the American auto industry treating us Canadians and the rest of the metric world like second class citizens. You in the US all enjoy your wonderfully efficient 230 mpg, whereas we are stuck with only 98km/L, less than half!! For shame.
I plan to start a boycott until this terrible treatment of the metric world halts.
Who's with me?
Why in the hell couldn't GM have just come out with a normal 50MPG car that didn't suck ass like the Metro? That would sell well and be a ton cheaper to make.
I am becoming gerund, destroyer of verbs.
>Power plants are much more efficient than the engines in cars,
True... only that assumes we are building more that will be able to supply the expanded demands on the grid.
It's been how long since we've built a new nuclear plant in the US? Coal is being attacked at every turn, solar and wind still being too expensive and too inefficient to meet current demands.
If we see massive purchases of plug-in cars... you are going to be seeing more rolling blackouts and exploding costs of all forms of energy... and not just in California.
Help Brendan pay off his student loans
How many gallons of electricity does it hold?
My UID is prime. Hah!
As stated in the summary, that's the EPA's rating, not GM's rating.
While I agree with you in your evaluation, keep in mind that detractors can point to the "government" (EPA) and to GM and say they're the same thing.
It doesn't hurt to be nice.
I'm not sure why people are hating on this car so much other than the fact that it's GM and everyone is mad at them for the whole bailout thing right now.
.75 gallons? You're going to complain about that?
The only real difference between this car and previous hybrids is that this one will go 40 (maybe, I'm guessing closer to 30) miles before it kicks into hyrbid mode.
This car is a great concept and for the vast majority of people I know, will provide essentially gas-less lifestyles (except on road trips, but if you're taking THIS little thing on a road trip, you did something else wrong). And if you need to go 70 miles instead of 40 in one day, you spend what?
This is the kind of technology that can break the oil companies hold on the auto industry. yet people continue to bitch about how it's not good enough for them. I say fuck you all and I hope other companies follow in this car's footsteps. All technology has to start somewhere and this is the first version of a gas-free car to hit the market. Give it a few years and we'll be seeing cars that go 60 miles on one charge, then 100, then maybe even more. Give it time, stop bitching and appreciate how far we have come, not how much you still want to happen.
That is not an argument to stop building electric cars. That is an argument to start building more powerplants.
Which is a good idea, and another discussion.
'Sensible' is a curse word.
So I guess there is no conflict of interest there?
The Chevy Volt has great mileage, by Presidential Executive Order.
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
From The Atlantic: GM's Volt Offers Amazing Mileage, But At What Cost?
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So its hype and a bogus test meant to exaggerate the car in best possible situations.
Or, for people who live in an optimal situation, say 20 miles from work with mostly in-city driving, it is as great as advertised.
I drive a TDI Golf. I get 45 MPG. But it's all high way, 80 miles a day. If I were driving stop light to stop light, my mileage would plummet. Diesels with a nice short final drive are the kings of the highway, but full electrics dominate on surface roads with lots of stop and go action.
Also, not sure on the Volt, but I believe Toyota offers a battery recycling plan that dramatically drops the cost of replacement, and I think the more recent generations of batteries are shooting for 10 year service windows.
If I had a 20 mile or less commute in a town of more temperate weather, I would definitely look at the Volt as a serious contender for my next vehicle.
-Rick
"Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
RTFA.
They discuss the electricity consumption/cost in the article, and that the number is an estimate that's hard to calculate since many people will use the battery exclusively about 75% of the time.
I agree, it's hard to calculate to give both an accurate and realistic number. If you drive non stop until the car both runs out of electricity and petrol, then calculate distance/gallons then that's an accurate number. But is it realistic? This car isn't designed for the cross-country road-trip in mind, but even still it would get hybrid (or better) mileage due to charging over nights.
So what number do I care about? Driving cross country or day to day driving?
Similarly I could try driving my hybrid on the highway, flooring it the entire way and I wouldn't get the advertised numbers.
Granted, it would be nicer to know "how many bushels of coal are needed to charge it to capacity" and then try to find an analogy between bushels of coal -> gallons of diesel -> gallons of petrol. Then you can say those 40 miles required so much diesel, which is about so much petrol. Then again, the entire country doesn't use coal-burning-plants so even then it wouldn't be accurate.
> It's just like the people who drive "green" cars like the Prius. Do they not
> realize that the car will only run for about 100,000 miles before they have
> to replace some ridiculously expensive component? "But it's for the
> environment!" they'll claim. So the majority of consumers in the USA are
> concerned with "the environment" over their pocketbook? I think not...
Source please? Our neighbors purchased the first Prius in our metro area, and Toyota gave them a thank-you gift of a lifetime warranty so they have no incentive to under-report problems. Their Prius is around 120k and has had zero major maintenance required. Including batteries. That's pretty typical of Prius experience I have read about.
sPh
The 230 figure is designed to account for how most people will drive the vehicle and uses a government standard test methodology. The important thing is that the same test is applied to all equivalent vehicles. Since 90% of people drive 40 or fewer miles in a day, it's not an unreasonable number if recharged as designed.
If you wanted a better figure of how it would last for a day's worth of driving you could take the total driven range and divide that out to get miles per gallon. Perhaps even quote it with a qualifier as something like 100MPG/300kWh to account for the electrical contribution (my figures are made up but you get the idea). This would allow to easily account for the cost of the electricity as well as the extended range from batteries and post battery range once you have drained the initial charge.
Regardless of how you interpret the results the car is impressive even if it is too expensive. Give it a few years and you should be able to get something like this for a lot less money. I've already talked over with my wife and we want to get a vehicle like this and solar panels on the roof in about three years when costs drop. I figure it should drop my monthly expenses a fair bit and be good for the environment.
Of course the VW Polo gets good mileage; the engine only puts out 74 HP. The Volt electric engine is rated at twice that (150 HP), and still manages good efficiency overall.
Have fun trying to get up to highway speeds or up a steep hill in your Polo.
I wish they would have kept to their original listing of "40 miles on a single charge, 50 MPG when running off the generator". The EPA needs to come up with some new measuring standard for this type of car, or some idiot is going to put one gallon of gas in his uncharged Volt for a 200 mile trip one day, and bitch and moan when he runs out of gas in the middle of nowhere after 50 miles.
Sounds like the MPG is non-issue for this car, unless it's operating beyond that 40 mile range. In that case, we need something new....
Miles per dollar?
Miles per kilowatt?
Miles per Newton (or whatever we can equate all fuels to)? (i have no idea)
In any case, the 40 Mile range is AWESOME for some people. i could go for a few days w/o charging.
Utilizing the synergization of benchmark e-solutions to pre-workaround action items!
If cars like the Volt and the Leaf even LOOK to be successful, oil traders will begin to run from the market, sending oil prices plummeting.
Is it not possible to calculate the thermal heat in 1L of gasoline when burned at STP at the stoichiometric ratio? If we can get BTU or BTUh out of it, we've got something to work with.
Then compare that to the kWh at your power meter to charge the vehicle enough to travel until the battery system shuts down. (Disable the gasoline system on Volt-like cars.) Count miles. Repeat, average, etc.
I was able to find the right figures for natural gas, so I was able to figure out if it was better to use a single-room space heater or turn up the furnace. (Unsurprising result: A little bit of electricity for one room is better than a lot of gas for the whole house.)
They're also throwing around figures like "40 cents to charge, for 10 kWh, at Michigan off-peak rates." OK, sure, but in Ontario, that'll set you back over a Canadian dollar, as almost nobody has time-of-day metering. Massachusetts will be closer to $2 USD (20 cents/kWh)--which is still half the price of gasoline at last summer's prices in Ontario ($1.25/L).
Here we go. 125,000 BTU in 1 gallon of gasoline, which is about 37 kWh.
So, at 40 miles/10 kWh we've got 4 miles/kWh, which I didn't need Google for but so you can see what I'm doing (show your work). That's the easy one.
I've seen 50 miles/gallon cited for the Volt, so we want miles/kWh... 1.36 miles/kWh.
Both of those are "at the pump/plug" numbers: What you use in electricity net of any generation and transmission losses, compared to volume of gasoline from the pump at your filling station net of energy used to process it from the Alberta tar sands.
(My physics teacher would freak out at that SI and US Imperial unit soup, too.)
What I want to know about all of these electric things though... especially if they're quoting Michigan off-peak power prices... what happens in winter? Those of us in northerly climates don't just throw away all of the thermal inefficiency in the internal combustion motor. We vent some of it in to the passenger cabin as "heat". I'm not giving that up; and resistive electric head for the passenger cabin will kill your battery range real fast--everyone's left just the headlights on and needed a boost at one point, right? That's only about 180 Watts (two headlights + assorted markers.)
I'd be worried that if all my runs were full-electric, that is to say that my 10 mile commute never required the car to dip into the gasoline, that without treatment, the gasoline could break down and gum up the injectors - like when you store a boat or mower over the winter...but who wants to drive around with a stabilizer-mix full time? that's gotta put a big hit on efficiency and power if you ever need the combustion engine to kick in.
i don't think i've ever seen that issue discussed when hybrids are brought up.
That was my original reaction. Based on the CNN Money article especially, they seem to be making the assumption that, in battery mode, the car would use not only no fuel, but no energy.
But they I saw the claim that the charge to take the car 40 miles would cost $0.40. That's a penny a mile, and at current gasoline prices of about $2.50 a gallon, translates neatly into about 250 MPGeq (miles per gallon-equivalent, on a cost basis).
I agree that MPGs aren't the best measure, because it makes comparison between different vehicle types more complicated. $/M is not workable because the cost of different energy sources is not constant, and would just add another dimension to the already highly variable efficiency rating.
They will have to come up with something better, MPG is just not going to be useful as EVs begin to penetrate the market. The best would be some form of distance per unit of energy, or energy required to travel a certain unit of distance. There would have to be some way to correct for any losses. One virtue of MPG is that this is built in. Take the miles you drive and divide by the number of gallons of gas you buy, and the resulting number automatically takes into account any losses due to heat, operating conditions, evaporation, or whatever. I is straightforward to convert a gallon of gas to the HP or KWh it contains (although I don't have the coefficient at hand, I'm sure it's easily found). For electric drive, it would be easy for the control system to determine how much power it's drawing from the battery, but there needs to be a way to correct for the fact that you will necessarily be putting more energy in than you will ultimately get out, either using some estimate of the battery's efficiency (probably not a good idea, since that will change over time), or maybe circuitry on the charger that will measure the total energy put into the battery (which adds complexity).
Right now, though, they needed some quick and dirty way to come up with some comparison between the Volt and its competitors, all of which measure their efficiency in MPGs. If they really can get 40 miles out of $0.40 worth of electricity, then at today's gas prices, yes, the 230MPG claim is credible. However I don't know how credible that particular claim might be.
*range is 100 miles
Gray Davis did.
The example that illustrates the point. As the wiki points out, Davis would have been happy to stop the brownouts, only the only clear way he could have done that is by removing price caps on long-term contracts that had been established through California's energy market de-regulation (CA de-regulated its power grid, but established caps as some sort of hedge against.. er... power generation companies and market makers abusing their position by creating artificial scarcity).
It's sort of a bad example, because none of the brownouts at that time were caused by a lack of generator capacity; it was all caused by Enron and Reliant calling up their plants and telling them to call in sick for the day, causing spot prices for power to rise on account of lower supply, and calling their other plants and telling them to ship their capacity to Nevada, so they could (1) arbitrage cheap Nevada power into expensive California power and (2) sell transmission line capacity to themselves, causing the price of transmission capacity to go up and making the cost of piping the California poer to Nevada and back even more profitable.
Don't blame me, I voted for Baltar.
Electricity costs me $0.19 per KWH and it takes 10KWH to fully charge Volt's batteries, for a total of $1.90
Gas around here is about $2.50/gallon, so a full charge is equivalent to 0.76 gallons of regular. Which means 52.6 mpg at my current gas and electricity costs. After the charge is exhausted, the car is rated for 50 mpg.
However, I live NJ, so our gas is cheap and electricity expensive. In other places the math might be drastically different.
If con is the opposite of pro, is Congress the opposite of progress?
Very weak. 40 miles on battery and then ~ 50mpg for the remaining 10 miles and you get the stupid mileage figure. Yes you can average 230mpg over the first 50 miles you drive on a fresh charge. Of course driving just another 10 miles would drop the mileage figure substantially. I guess it's time to have two mileage ratings. The first would be gallons per 100 miles with a fully charged battery, the 2nd would be gallons per 100 miles on a fully depleted battery.
_GP_
I bought my 2002 Prius after a six month wait time. I paid more for it then a comparably equiped gas car. There was no economic rationale for my purchase -- I did it because I loved the car, and had the privilege of driving a cutting edge piece of engineering for going on seven years now, with minimum maintenance and hassle. There's something beautiful about driving with virtually no noise and I still smile when I roll up to a stop sign and the engine shuts off.
Moreover, I am willing to pay higher than market rate because of the externalities associated with having the world's first mass-produced electric car:
I am supporting an environmental technology that I believe in.
I am supporting green-tech projects, built in America.
I love driving on electric power only.
I am willing to take a risk on buying the Volt or the Prius or any other quasi-experimental first-generation piece of tech hardware because I have the money.
I am buying it because as a child I wanted to know why I couldn't put a windmill on top of the family car and use wind power to make it go.
Maybe Chevrolet's engineers are just insisting on being thorough and working the bugs out BEFORE release... which is a concept too many software engineers seem to have forgotten? That fleet of 50 "beta" Volt cars that's been on the road wasn't just for advertising, ya know.
Sorry, but buying any new car is the opposite of being green. A lot of polluting resources go into manufacturing a new car. If you want to be green, you (in order) move to within walking distance of work, take a bus/train, or get a fuel-efficient used (already manufactured) car.
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
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...why do these stories about hybrids, fully-electrics, etc. always elicit responses like "but it freezes here, which kills performance" and "but I drive 200 miles every day, will it be able to do that? No."
I don't hear anybody ranting on the Mini for not being able to support a soccer (hockey?) mom with her 3 kids+entourage+equipment.
I don't hear anybody complaining that a Ford Excursion is crap up in northern Alaska because the tires keep sinking into the thawing dirt roads.
Who last complained about a Scuderia Spider (open top car) because they lived in Seattle and, well, dur?
Not every single car is going to fill your specific needs and desires; thank goodness, then, that there is a wide range to choose from.. and with the Volt and other initiatives, those whose desires include having a non-gasoline car to drive short distances regularly in non-extreme (4 months of freezing is extreme enough, tyvm) weather will be having that choice available to them, just as you have had the choice between a myriad of cars that will happily run with little performance loss at 30F and the heater blasting at full.
Peak electric use is during the day. Cars will mostly charge at night.
They're using surplus capacity; no new plants needed.
Welcome to the Turing Tarpit, where everything is possible but nothing interesting is easy.
The SI unit you might be looking for is Joule. Every form of energy can be brought back to Joule - be that electrical energy or chemical (potential) energy.
http://en.wikipedia.org/wiki/Joule
It doesn't get 230MPG. It gets 230MPG if you start on battery, drive until the battery is dead, and then drive a little bit farther on gas. You must consider that the energy that was stored in the battery had to come from somewhere, namely the on-board gas-fired electric generator. Of course, since they don't consider gas that was burned putting that energy there for the test, they can claim these ridiculous numbers.
It's all an elaborate fraud designed to dupe people...
I read somewhere that the method the EPA is currently using to measure mpg for these cars is to see how much fuel is consumed for 51 miles. What happens is the car runs on the batteries for 40 miles, then on gas for 11 miles. So, the average for all 51 miles was 230G, which means the total fuel consumed was approx .2217 Gallons. But, .2217 Gallons / 11 miles approx. = 49.62 MPG (when not running on the batteries).
If the EPA used any value less than or equal to 40 miles, the car would appear to get infinite miles per gallon. If they used 41 miles, then it would appear to get 2034MPG. Basically, by choosing how many miles to use as your 'standard', you can really choose *any* value > 49 for MPG. As the miles increase, the value would asymptotically approach the true MPG when running on fuel.
Because if you put in some gasoline in a new one it will still be there a decade later when you look again.
I will be interested to see if it can hold a charge for 40 miles when it hist -20 in Minnesota. I know Li works well in the cold compared to other batteries, but there is still an effect.
A plug-in hybrid's "miles-per-gallon" rating can be made arbitrarily high -- it just depends on the gasoline/grid electricity "blend assumption" made during the calculation.
So you can see why a miles-per-gallon statistic is worth very little when it comes to plug-in hybrids.
Instead of coming up with an arbitrary blend assumption that won't exactly match the behavior of any driver, the EPA should simply publish two economy ratings: the miles-per-gallon when the car is propelled strictly by gasoline, and the miles-per-kilowatt-hour when the car is propelled strictly by grid electricity. Yes, this is more complex than publishing a single figure of merit, and a small percentage of consumers will never understand it, but on the other hand, it would cause lots of consumers to study the issue and actually learn something. And avoid the unrealistic hype of "zomg, the 230 mile-per-gallon car!"
How about miles per pound of carbon dioxide emission?
No good. This figure is also going to vary quite a bit, depending on the assumed gasoline/grid electricity blend. (Plus, not everyone buys into the alarmism over CO2.)
That that is is that that that that is not is not.
A good heater shouldn't require more than around 1.5 kilowatts, the size of a space heater that can keep a small room toasty. The Volt's engine is rated at 111 kilowatts.
So running the heater shouldn't cost more than around 1% of your total range.
111 kW is the peak output of the engine. Your math only makes sense if the engine is running at peak output the entire drive, but not during normal driving conditions.
First I'll make an intuitive argument: Peak engine output would only happen if you're flooring the accelerator. In this case, the batteries will discharge rapidly and you will travel at a high speed. Ignoring second-order effects, the car will still travel the maximum range of the batteries (i.e. 40 miles) but in a very short amount of time. Intuitively, if the heater is only turned on for a short amount of time compared to the distance traveled, it won't have a large effect on range.
Now, we can look at a more sensible way to determine the effect of the heater: look at the capacity of the batteries. Wikipedia tells me that the batteries can store 16kW-hours. It also tells me that the range of the electric motor is 40 miles. Again assuming no second order effects, we can assume that a 20 mile drive consumes 8kWh (distance/maximum distance * battery capacity). Given your assumption that an electric heater pulls 1.5kW, it's easy to plug in some numbers:
20 mile drive @ 60mph -- 8kWh consumed by engine, (1.5kW * 20 minutes) = 0.5 kWh consumed by heater
20 mile drive @ 40mph -- 8kWh consumed by engine, (1.5kW * 30 minutes) = 0.75 kWh consumed by heater
20 mile drive @ 20mph -- 8kWh consumed by engine, (1.5kW * 60 minutes) = 1.5 kWh consumed by heater
Case 1: 8/8.5 = 94% efficiency (-6% range)
Case 2: 8/8.75 = 91.5% efficiency (-8.5% range)
Case 3: 8/9.5 = 84% efficiency (-16% range)
As speed decreases, the more the heater affects the range of the car. Again, this is intuitive, because at slower speeds, the heater is operating (and draining power) for a longer period of time compared to distance traveled. 20-30mph speeds are common during a typical heavy commute and would reduce range by up to 15%, much more than the 1% you predicted.
And to show that the peak wattage calculation does indeed work assuming maximum speed, we can take the quoted maximum speed of the Volt's engine (180mph) and use my method above:
20 mile drive @ 180mph -- 8kWh consumed by engine, (1.5kW * 6.6 minutes) = 0.16kWh consumed by heater
My method: 8/8.16 = 98% efficiency (-2% range)
Your method: 111/112.5 = 98.7% efficiency (-1.3% range)
The two are very close considering that most of the assumptions I've made about performance aren't accurate at extreme high or low speeds.
"This new bogus number is because of GM working with/lobbying EPA. I can't believe EPA caved into such a content free meaningless number."
Why not? It's just one federal government agency working with another one!
Here is more background on GMs push for this kind of rating:
http://www.bloomberg.com/apps/news?pid=20601103&sid=a2GgcMQbsIcU&refer=us
"General Motors Corp. said it reached a preliminary agreement that clears the way for U.S. regulators to certify the Chevrolet Volt, an electric vehicle that can be recharged at home or with a 1.4-liter gasoline engine, as the first 100 mile-per-gallon car."
When I read this article last year it sounded like GM was pushing forward this kind of nonsense measurement. Sound like a coup for GM.
Lets do a little real-world figuring.
It's 14 miles to work for me. If I drive it to work each day, my mpg is going to be infinite.
Town is 20 miles 1 way, so 40 miles round-trip. If I can charge it back up before going to the gym, my mpg will again be infinite. If not, it will likely be very, very high.
I do go on long trips during the weekend, about 500 miles last weekend. OK, if it's getting 49 mpg on the open road, which isn't all that much of a stretch considering the aerodynamics, hybrid mode with the regenerative braking and all, I've still got a winner with 460 miles at about 49 mpg = 9.38 gallons. That's going to look real good at $4 a gallon, and... how about $7 a gallon? In case anyone was wondering, an economic "recovery" is impossible because as soon as there is prosperity, the ragheads will jack up the price again, and the more prosperity, the higher the price. They'll make as much money as they can while once again ruining our economy. And, they'll be able to do it, until we all buy cars like this one, and can tell them to stick it.
As for the battery in 10 years, how do you know what a battery is going to cost in 10 years, or whether this one will need one? There are hordes of science people working on battery breakthroughs, and someone is likely to be lucky or good in that amount of time, and this car will then go 300 miles on a charge, charge in 3 minutes flat, and cost $200 for a new battery. Well, it could happen... But we have to start thinking seriously about these sorts of vehicles, or we're going to continue to be toast, and easily defeated by those with the oil.
Why are there so many haters on this car? If anyone thinks that this is the end all be all solution to the problem, they are freaking idiots. This is just the first volley across the bow of the PRACTICAL electric car idea. With mass production brings decreased costs and better technology over time. If all car companies waited until the technology were perfect before producing it, it would be another full decade before anything hits the market. Yes, GM has screwed up in the past, but don't hold that against them with this car. THIS IS A GOOD START.
http://www.tomandemily.com
So what is the milage rating of the tesla Roadester or the Nissan Leaf ?
... <insert infinity symbol>
How about
G
There's something wrong with a calculation method that yields a claim of "230 miles per gallon" for a vehicle that cannot drive 230 miles on one gallon of gasoline.
Energy by conversion is never environmentally friendly in any form. Hydro wrecks the landscape, burning fuels pollutes the air, nuclear creates radioactive waste, and even solar, wind, and wave have negative impacts on the environment. The only way to truly protect our environment it to produce the cleanest energy possible and use that energy responsibly, and sparingly.
So... what's left? Maybe we should start doing things that are less bad to the environment right now and progress towards that, rather than just argue how we can't live without doing bad things to the environment and just give up on it.
Interesting.
They should specify Mpg given two figures:
(1) Average Mpg + Kwh (loss of charge) given a very long trip, e.g. 48 hours of travel around the city since the last plugin. Given that the vehicle started with a full charge, and will not be allowed to be plugged at any later time during the trip.
and
(2) Average Mpg + Kwh usage for a short trip, say 6 hours.
The problem is the one synthesized figure doesn't give everything you need to know to understand the efficiency
Some people will be primarily interested in the amount of GAS the vehicle consumes.
Others will be interested in the cost and the total overall environmental footprint. Considering this is not a solar powered car; the electricity it utilizes costs something.
It could use less gas but still cost more, if it has large batteries that need to be charged, and the Kwh consumption of a short trip is high enough. Esp. consider also the weight of the added batteries.
Also, there is this matter of, what happens to the Mpg, when the batteries run out of juice, and the trip has only just begun?
Depending on the type of battery, capacity may be lost over time also, and the vehicle may soon drop close to 50 mpg, within 5 or 6 years of purchase
And what if your IC-based car has the transmission crap out at 10 years?
In theory, the Volt's electric drivetrain should be really reliable and require almost no maintance, and the Volt's gasoline engine which only has to run occasionally and at a constant speed should likewise last a long time and require little maintaince*. On the other hand, the IC-based car, all other things being equal, will require more maintance and will probably require more repairs over the same time period.
Besides, if the Volt's gasoline engine is good enough to charge the battery while on the freeway, then even if the battery is completely shot the car should still be drivable and therefore not worthless.
*Not that I would be surprised if GM managed to screw this up
Fair enough, I just think it's a little jaded to think that all environmentally friendly labelled products (or cars, VW Diesel TDIs, Priuses, etc.) are not doing some part in helping the environment as opposed to other, less environmentally-friendly, options. I agree that greenwashing certainly occurs, but Luddism isn't a choice for pretty much everyone and that there are more responsible choices out there.
Interesting.
Small city commute is for me up to 10 miles (twice , so up to 20 miles a day). I keep hearing car , car , car , mpg, mpg , mpg, and I SMILE. With such a small commute you can use a *bicycle* and have a bajillo miles per gallon, and do sport, save on car cost (I have a 11 miles commute). Sure you have to be a bit more warry on car, but if you live in a city with bike lane (I do) this can be very safe. Lately I even added a trailer on it so that I can buy up to 80 kg of stuff, so I need only a car ONLY in case of 1) medical emergency 2) non city commute. 230 MPG ? HA !
C. Sagan : A demon haunted world:
http://www.amazon.com/gp/product/0345409469/
visit randi.org
I really don't think this is the end of the world. And the best part- for us nuclear fans- is that a big electricity crunch would be just the stimulus needed to build new plants. I know it takes a while to get them online but the transition to electric vehicles won't happen overnight, either.
Ah but nuclear power plants can't be built as fast as wind turbines can. Doing a quite search the Salem Nuclear Power Plant was the largest electrical generation nuclear powerplant. It has 2 reactors, one capable of generating 1,174 MW and the other 1,130 MW for a total of 2,304 MW. However if you erect 20 5 megawatt wind turbines a month in 2 years you'll add 2,400 MW of capacity. Could a nuclear powerplant be built and brought online in 2 years?
Backed by French government loans Areva, also owned by the French government, started building the Olkiluoto Nuclear Power Plant in Finland in 2005. Originally it was scheduled to be built in 2009 as "the world's largest and safest nuclear plant". Today, it's not scheduled to be finished until 2012 at the earliest, and it's 2 to 3 billion dollars over budget. Fact is is cost overruns for nuclear powerplants considerably add to their costs. As the freemarket institute CATO reprint of a "Forbes" magazine article says, the nuclear power industry is "Hooked on Subsidies". Notice where it says "How do France (and India, China and Russia) build cost-effective nuclear power plants? They don't. Governmental officials in those countries, not private investors, decide what is built. Nuclear power appeals to state planners, not market actors."
Falcon
Should there be a Law?