AND 
Calculating the Volts EPA Rating, More than 100 mpg?
Bloomberg has reported that the EPA has reached a preliminary agreement to awarding GM a 100 mpg window sticker EPA rating for the Chevy Volt.
This information reportedly came from Volt vehicle line director Tony Posawatz who noted that the EPA agreed to use a testing method that would produce at least a 100 mpg result. GM has indicated this article was inaccurate.
GM spokesperson Rob Peterson today advised me that GM has been continuing discussions with both the EPA and CARB. He noted GM has reached a preliminary agreement with CARB (not the EPA) who has agreed to classify the Volt into a “unique” category that sets it aside from hybrids and EVs, calling it a “type G” vehicle. He also advised that we are several months away from determining a Volt sticker rating, and that it will undoubtedly require road testing of pre-Volts to do so. The number 100 or greater is far from final.
I spoke with Mike Duoba who is a national expert on plug-in hybrids at the Argonne National Lab and who chairs the SAE committee charged with developing efficiency labeling standards for plug-in cars.
He describes a methodology typically used called the full charge test. In this test, the E-REV runs through standard federal driving cycles until the car switches from charge-depleting to charge-sustaining mode. It then runs for an additional cycle. One then calculates the gallons of gas used over the number of miles driven.
This number would then be adjusted by a utility factor. This value takes into account the entire population of drivers’ driving habit. For example as is the case of the Volt, 78% of drivers drive less than 40 miles, so since few are at the extremes of range, lower mpgs at those ranges would have a small contribution to the final number.
Mike feels the window stickers will have to be simple and allow people to compare among types of cars, but thinks it is likely and appropriate for the Volts mpg to wind up greater than 100.
He acknowledges that the EPA will take the recommendations of his committee into account when they finally issue the public statement, but are not obligated to be held to them.
Remember, first 40 miles, infinite mpg. After that roughly 50 mpg, but less than 20% of daily drives go beyond 40 miles. What does this mean to the consumer?
Source (Bloomberg)
102 Responses to “Calculating the Volts EPA Rating, More than 100 mpg?”
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September 26th, 2008 at 2:27 pm
Be interesting to see Toyota’s reaction to 100 mpg.
September 26th, 2008 at 2:33 pm
Be interesting to here ALL the other car makers reaction to it
Also you would think they would want it in the same class as regular cars to improve there fleet rating or I’m missing something?
How many days till I can order my Volt?
September 26th, 2008 at 2:38 pm
Does the Volt use regenerative charging like the Prius does? If you coast down a hill, brake, or release your foot from the pedal, is the traction motor doubling as a generator? If that is the way it works, it would seem that “first 40″ could be quite variable before the gas engine kicks in. If the traction motor is “just a motor” and not a generator, then the “first 40″ will be determined by the terrain the user drives in. My daily commute is about 55 miles. In each direction I have to climb over a mountain. In the Prius, it means the gas engine works significantly going up the hill along with the battery boost, but coming down the other side, the engine is off and the battery fully recharges. After you take the “goin’ over the mountain” out of the equation, my trip is sort of downhill to work, and uphill coming home. I get better millage going in to work vs. coming home (but a tankful still averages out to 48mpg).
How would this type of trip be handled in the Volt? Would I expend an disproportionate amount of battery power climbing over the mountain, and not recoup it going down the other side? If so, my “first 40″ might not be 40 at all.
In any event, a Volt would certainly allow me to use even less gas than I would in the Prius. Of that, I’m confident. Bring it on!
September 26th, 2008 at 2:41 pm
This seems to be a continuation of the discussion to the September 6th topic:
How Should the Chevy Volt’s mpg be Calculated?
http://gm-volt.com/2008/09/06/how-should-the-chevy-volts-mpg-be-calculated/
September 26th, 2008 at 2:44 pm
What I’ve seen on the Volt’s drivetrain is that it will certainly have some type of regenerative braking. I don’t think you’ll re-coup 100 percent of the energy expended going uphill that you would going downhill, but you’d re-gain some.
September 26th, 2008 at 2:50 pm
From the article:
“He (Mike Duoba) describes a methodology typically used called the full charge test. In this test, the E-REV runs through standard federal driving cycles until the car switches from charge-depleting to charge-sustaining mode. It then runs for an additional cycle. One then calculates the gallons of gas used over the number of miles driven. This number would then be adjusted by a utility factor. This value takes into account the entire population of drivers’ driving habit. For example as is the case of the Volt, 78% of drivers drive less than 40 miles, so since few are at the extremes of range, lower mpgs at those ranges would have a small contribution to the final number.”
Mike feels the window stickers will have to be simple ….
———————–
Umm…no.
What is so bloody hard about this:
EV Range: 40 miles
MPG: 50
Easy and accurate for everyone. Any flat XXXmpg will be INACCURATE and confusing for ANYONE.
I know the 100MPG is sexy, but those stickers aren’t slapped on all those cars to help the manufacturer sell them…they are there to inform the customer in the most reliable way possible of the REAL WORLD performance of the car they are standing in front of.
September 26th, 2008 at 2:53 pm
#3 Jeff Regen breaking yes, But a lot bigger battery needs more time to charge. My guess is the downhill will not charge it fully.
September 26th, 2008 at 2:55 pm
I think 100 MPG is too low. Using a typical yearly driving pattern of:
• 30 days at 8 miles per day
• 50 days at 16 miles per day
• 240 days at 30 miles per day
• 30 days at 60 miles per day
• 3 days at 450 miles per day
and assuming one charge per day (usually at night), the Volt averages 314 MPG. This type of yearly driving pattern seems fairly typical to me, so 314 MPG is probably very close to a real world typical average.
Note that, using the same typical yearly driving pattern above, the Toyota Prius Plug-In will get 70 MPG. So this type of real world driving pattern shows how stark the differences are between various types of plug-in cars.
Also note that throwing in a fudge factor to account for electricity usage is not a good idea. Electric utility rates vary dramatically from one location to another. Electric utility rates will also increasing vary by time of day, with significant discounts offered for night-time charging. And if you buy a wind turbine or home roof solar system, the electric rate will be near zero.
September 26th, 2008 at 2:55 pm
Honestly, they could’ve just done something as simple as this…
On the sticker show:
“battery milage” (40 miles)
“MPG after battery depletion” (50 mpg)
September 26th, 2008 at 3:00 pm
This is so wrong to exclude the cost of electricity in the battery.
There must be a means of converting the electric power to M/G.
I expect 75 M/G is a much better figure.
September 26th, 2008 at 3:07 pm
#10 Jonathan
I pay $0.17 per KW (Wind energy). Round that to $0.20 by the time the Volt comes out. A 8 KW charge would be $1.60. Therefore if gas is $3.20 a gal. (good luck on that price) the electricity cost would equal 80 mpg.
September 26th, 2008 at 3:08 pm
Well, for my own purposes, I would understand it to mean that under most circumstances I would not require fuel, and depending on my options package may get some slight benefit from my solar cells but will rarely get full from them unless I have to leave it at the airport for a few weeks (more common then you’d think…I also want the solar roof to keep the battery cool during this period). Then the gas engine factors in, where I know that after I am done with my initial charge, I will have to operate on a very efficient but obviously more expensive source till I can plug the thing in again.
I hope that in the owners manual, which I do want to read when it comes out (do they publish these on line?) they will clarify everything.
I’m still not overly worried about the car ‘looking’ high-tech, I’d actually rather have the ‘grantmobile’ blend in with the rest of the parking lot herd so no one tries to take my battery. This will be my first car with a security system…
September 26th, 2008 at 3:08 pm
These discussions are about more than just the sticker – the EPA number figures into GMs CAFE number.
September 26th, 2008 at 3:11 pm
The EPA window sticker is designed to show MPG (Miles Per Gallon), so you can compare it to other cars. It was never intended to show the COST of anything, gas electricity, plutonium…. You can’t show the COST of the electricity per mile because, well, that cost varies by location, date (Goes up over time), and even time of day for some with special electric meters.
If the EPA gives it a 100 mpg rating, so be it. It deserves an extremely high mileage figure to grab attention of the masses, given the huge gamble automakers are taking on the technology.
Remember 99% of the country, probably the world, have no clue what an E-REV is. Hell, most people don’t know what a hybrid is yet.
September 26th, 2008 at 3:13 pm
GM commercial, circa 2012:
” …your mileage may vary. It could be MUCH higher. See your local Chevy dealer for details… “
September 26th, 2008 at 3:13 pm
#6 Statik
“What is so bloody hard about this:
EV Range: 40 miles
MPG: 50″
Agreed. If they use the proposed method, some people will get numbers way less than 100mpg (down to 50mpg) and others will get way more than 100mpg (100mpg to infinity). Doesn’t make any sense. I foresee alot of confused faces at the Chevy dealerships in the upcoming years when told 100mpg (assuming the Volt ever is sold, hehe). People have the capability to understand that there are two different driving modes. The EPA and GM are trying to make it “simple” but is ending up making is more complicated. Grrrr….
September 26th, 2008 at 3:16 pm
For better or worse, it sounds like they’ll end up with a simplified composite number to try to help most average consumers, based on something like the standardized formula described above…
We would still need to see something that would help actually compare with other similar models: perhaps miles per kW for the electric motor, kW per gallon for the generator, and usable power in the battery. How else can you really contrast the efficiency of the electric motor to actually drive the car, separate from the generator or total AER? Different consumers would want different capabilities, like more AER (larger battery) vs. efficient longer drives (efficient drive and/or generator)… I suppose those details would be in the fine print somewhere.
So, (like I now see Statik and BuddyP mentioned above), perhaps we could narrow it down to the two distinct numbers we usually talk about– how many all-electric miles per charge (at low/high speeds), and average miles per gallon on generator only. Anything else hides the facts and leads to shenanigans to inflate the rating that may not translate into the real-world…
Got plug?
=D~~’
September 26th, 2008 at 3:16 pm
From the topic thread article:
“Bloomberg has reported that the EPA has reached a preliminary agreement to awarding GM a 100 mpg window sticker EPA rating for the Chevy Volt.
This information came from Volt vehicle line director Tony Posawatz who noted that the EPA agreed to use a testing method that would produce at least a 100 mpg result.”
———————————————-
———————————————-
“Reports out this morning on Bloomberg and the Detroit Free Press indicated that GM and the EPA had reached an agreement that would potentially see the Volt as the first car classified with a 100 mpg rating are ERRONEOUS.”
We called spokesman Rob Peterson to get the scoop, and it turns out that GM has reached an agreement with the California Air Resources Board, (CARB) on a unique classification for the Volt. Peterson told ABG that this classification would reflect the Volt’s true capability, essentially treating it as an EV.”
Source: http://www.autobloggreen.com/2008/09/26/gm-reaches-agreement-with-carb-on-unique-classification-for-volt/
The agreement with CARB gives GM a bargaining chip in its talks with the EPA, but Peterson cautions that the automaker and the federal agency “still have a long way to go” to finalize any agreement. The Volt may yet get that magic 100 mpg rating, but it’s not there yet.
September 26th, 2008 at 3:18 pm
Any type of MPG sticker is going to be misleading because the real answer is “it depends” and it will depend on a great many things, which are beyond the control of the manufacturer.
I agree with BuddyP, I think the real world number should only be the steady state number after the battery is in sustaining mode, which should be about 50 mpg, plus the EV range = 40 miles.
September 26th, 2008 at 3:24 pm
#12 Grant
The automakers make it purposefully very difficult to access batterys even in hybrids. I was reading about what it took to access the battery in an Escape hybrid, whew!
If someone wanted the battery from your Volt I would think the easiest way would be to just tow the whole car away!
Either way, a security system on a Volt would prob be a good idea.
September 26th, 2008 at 3:27 pm
I think the key is educating consumers… If we compare 40 AER/50 MPG to a very efficient ICE with say 60 MPG, how would the average consumer know that the first could realistically give them 300 MPG or more depending on their driving habits? Hopefully it won’t take long for it all to sink in…
Got Plug?
=D~~’
September 26th, 2008 at 3:36 pm
#20 Stew,
I didn’t know that, Thanks! That actually does help me a bit. I thought with the existing bizarre catalytic converter thefts, the battery was one 400 pound chunk of valuables. I never plan to touch the thing (don’t have the heavy lift to do it anyhow) but I know some theives are unusually clever.
I’ll still take your advice and get the system, I want the solar options and NAV anyway, so after all that skipping the alarm would be kind of dumb.
Now to just figure out if the giant battery is what starts the engine. I hope so, one less part to worry about.
September 26th, 2008 at 3:40 pm
Grant
The engine is attached to a generator, which also acts as a motor to start the engine.
September 26th, 2008 at 3:54 pm
Just so everyone is clear:
When taking regenerative braking into account, you must remember that while braking or coasting your car will NEVER recover all the energy that was used to accelerate to cruising speed. The generator/battery system would have to be 100% efficient to do that…in other words you would be violating the laws of physics. My personal thought (just a gut feeling here) is that regenerative braking will have a relatively modest effect on all-electric range.
Personally I don’t know what to think about these gas mileage rating questions. The proposed method (driving to charge depletion point, then driving another cycle with the generator) seems reasonable to me. But it is indeed misleading. Maybe the “40 miles per charge, 50 MPG after that” idea is better. But those two numbers are variable as well, so I’m not sure it would be much more meaningful in the end.
September 26th, 2008 at 4:02 pm
My 2008 Toyota Prius gets about 45 MPG, and has been consistent +/- 3 MPG pretty much regardless of driving conditions. The monitor guage shows a much wider range, sometimes giving the illusion of 39 MPG or 55+ MPG, but when I fill up its mostly 44-46 MPG.
I would expect the electric motor and 1.4L gas engine GM will use to provide similar performance to the electric motor and 1.5L gas engine in the Prius, so a mileage of near 50 MPG when beyond the batteries initial range (say 30-50 miles depending) is very credible.
I am very much looking forward to this car. It is an amazingly pleasant ride when you don’t have the gas motor kick in. This will be a big improvement over the Prius.
I will get mine loaded, with the solar options and NAV. I just hope some of the improved solar cell technology is available in two or three years. As that is when I plan to put a new roof on my house anyway, and it would be nice to get 100% off the grid, virually zero petroleum.
One concern I have is wont the gas in the tank go stale if you don’t run the gas engine for say a couple months?
September 26th, 2008 at 4:03 pm
I don’t care what the sticker says. I just want to get it in my driveway ASAP!
NPNS
September 26th, 2008 at 4:03 pm
Sounds great to me. I like 100 mpg very much. Bet some owners will be getting 1,000 mpg if they primarily use it to commute.
I just turned down a chance to purchase a 2009 Toyota Prius that is due at the dealership by Oct 15th. Sticker price is going to be $29,155 plus taxes and fees. Leather seats, package group 3 and some stuff added that was ok, but things like $449 for XM Satellite Receiver Kit and complimentary XM service for 6 months. I don’t want Satellite Radio so that would be wasting my money. Plus a few other things they stick on most of us don’t want. I have been wanting to buy a Prius as a stop gap car, but have decided to wait a few more months to see what the Honda Insight hybrid is going to look like (price and features).
September 26th, 2008 at 4:23 pm
I still want to REMOVE the ICE and then get…. how many mile per dollar?
I do have some expensive electric rates.
How about the remove ICE mod. Can we do it? I can carry around a cheap quite generator that weights 50 lbs in a pinch.
September 26th, 2008 at 4:24 pm
The first 40 miles are not “infinite” miles per gallon except in the very narrow sense of “how much actual gasoline is being burned”.
The energy is still coming from somewhere — in the case of the US electrical power generation, much of it is coming from coal, so there are still CO2 emissions even when in electric mode.
The ANL methodology takes this into account. It uses the efficiency of transmission of electricity, etc. to turn a “miles per kWh of electricity” number into “miles per gallon of gasoline equivalent” number. Note that this number is very high (more than 100 mpg) for the Volt.
The million-dollar question here is how the averaging is done between (actual mpg when in gasoline-hybrid mode) and (equivalent mpg when in electric mode). Remember the former is about 50 mpg and the latter is something very large.
It sounds like ANL is pushing for a weighted average where the weighting is done according to a sort of distribution function of the driving habits of Americans. This is exactly what I would do if I had to design the system.
The real problem here is trying to reduce something that really should be three numbers (all-electric range, miles/kWh when in electric mode, and miles per gallon when in gasoline mode) into one number (overall miles-per-gallon equivalent). But the EPA has decreed that the public can’t handle more than one number, and so they have to come up with something.
September 26th, 2008 at 4:24 pm
#25 Stuart Says: “One concern I have is wont the gas in the tank go stale if you don’t run the gas engine for say a couple months?”
————————————————————————————-
Welcome to the forum. This question has been asked for around 14 months. We know a few things:
1) GM will likely use a bladder in the gas tank. This seals the gasoline from any air, which is supposed to make the gas last longer, maybe 6 months.
2) You can buy a gas additive that make the gas last a year or longer.
3) GM has said they will solve this issue in a very unique way, but we haven’t heard any particulars.
Anything beyond that is speculation.
September 26th, 2008 at 4:28 pm
“Mike feels the window stickers will have to be simple and allow people to compare among types of cars, but thinks it is likely and appropriate for the Volts mpg to wind up greater than 100.”
*** *** ***
It appears that part of the complication is that they want the consumer to be able to use a single set of estimates to compare mileage between ICE vehicles, HEV, PHEV, and RE EVs. Good luck. Let the wrangling continue.
September 26th, 2008 at 4:29 pm
Just a little bit on regenerative braking. Published figures from California indicate recovery of about 7%. For example if a car got 100 MPG without regen braking, it would get 107 MPG with regen braking.
If the EPA goes with the proposed method, it would not be an accurate measurement, and like the bogus initial ratings for hybrids, will have to be reduced by at least 25% in the future. One, the method does not account for the cost of the miles driven electrically, and two, the split should be 1/3 gas miles, 2/3 electric miles, so if the AER is 32 miles, the vehicle should be driven 48 miles, burning gas in its charge sustaining mode for 16 miles. And then the cost of the electric charge should be converted in equivalent gallons, and then the equivalent gallons added the the gallons burned over the entire 48 mile cycle. For example 8 KWH cost about $1.20 or 1/3 of a gallon. So if the car got 50 MPG for the 16 miles, it would burn 1/3 of a gallon. The mileage then would be 2/3 of a gallon for 48 miles or 72 mpg.
September 26th, 2008 at 4:31 pm
Lots of opinions about how to calculate the MPG for the Volt. It doesn’t really matter to anyone in the know. We know that the mpg is going to be high. Some will be higher than others by a factor of 10, others will be lower. It will all depend on how you drive the Volt — miles per day and number of gallons used. Most of us will go less than the 40 miles per charge and will use very little gasoline. We will have great mpg. Even if you do count the cost of electricity and some how work it into the mpg equation, the Volt will be an extremely fuel efficient vehicle.
Go GM and Go, Go Volt.
September 26th, 2008 at 4:33 pm
This reminds me of the movie semi-pro when Andre 3000 does an Alley-oop and the ref doesn’t know what to do
http://www.youtube.com/watch?v=CIKcIjbhsHE
September 26th, 2008 at 4:55 pm
#6 Statik
I agree.
40 AER – 50mpg
Someone please explain to this group the negative aspects of using AER with mpg. If it is current EPA tests, laws and/or policies, they have 2-3 years to fix it.
September 26th, 2008 at 5:00 pm
To those who want to pull out the engine, first, the car’s software isn’t built to work that way. The two operate as an integrated unit, this is not designed as a full-electric and trying to turn it into one won’t work well.
For a full-electric, try Chevy later, or Tesla now.
September 26th, 2008 at 5:02 pm
I agree.
40 miles electric-50 mpg
Simple. 100 mpg would be misleading and will sooner are later to a lawsuit of people saying ‘ It doesnt get 100 mpg!!! I drove it 100 miles and it took 1.5 gallens!!!
Why does goverment have to make things compicated? As simpla as 40 miles electric-50 mpg. I dont know why I keep repeating myself, but this shouldnt even be a question its so simple!!!
September 26th, 2008 at 5:07 pm
Jeff #35
I think it has to do with the fact that the EPA wants the average consumer to be able to make a comparison between vehicles with one set of figures. All cars sold in the U.S. must use EPA FE test results to advertise their vehicles. The problem is that the playing field has changed and as you point out so must they. Unfortunately asking the EPA to change is in fact asking Washington to change, but there is always hope.
.
September 26th, 2008 at 5:11 pm
My suggestion:
http://img221.imageshack.us/img221/9596/voltepavt2.png
September 26th, 2008 at 5:19 pm
#39 kubel
Nice. I like it.
=D~~~~~~~~
September 26th, 2008 at 5:23 pm
#39 Kubel, that’s EXACTLY what should be done.
Three numbers. (A) All-electric range, in miles. (B) Miles/kWh when in all-electric mode. (C) Miles/gallon when in gasoline mode.
The problem here is that the EPA wants ONE number, not three.
September 26th, 2008 at 5:29 pm
Not looking too great.
I just did some math.
Assumptions:
Using standard EPA HWY cycle (they always quote the HWY # as it is usually highest. In those with regen breaking, both cycles are pretty much equal, anyways)
That means 10.26 miles.
40 miles AER means 4 cycles deplete the battery.
41.04 miles travelled, 1.04 are on gas.
It then completes 1 more cycle while on gas, bringing the total to 1.04+10.26, or 11.3 miles
Now, we were quoted 100mpg, so using 100 miles per 1 gallon, the total distance is 40+11.3 or 51.3 miles. This calculated to 0.513 gallons to go that distance using the 100mpg figure.
that means it used 0.513 gallons to go 11.3 miles, or 22mpg.
However, this does not take into account their “utility ratio” or whatever it was called.
I’m not sure how that would change things, nor am I in a state of mind to think of how to calculate it.. it’s been a long day, hah.
September 26th, 2008 at 5:29 pm
Keep it simple:
Completely charge/fuel the vehicle.
Drive the vehicle until you have exhausted both the charge and fuel.
Your average is 57 MPG.
September 26th, 2008 at 5:31 pm
NPNS!!!
September 26th, 2008 at 5:50 pm
I just checked again. The city cycle is actually longer.
11.04 miles
making it 55.2 miles travelled, 0.552 gallons (using the quoted 100mpg number), 15.2miles in 0.552 gal is 27.8MPG
Again, I can’t reverse the “utility factor” as I don’t know how it is calculated.
September 26th, 2008 at 5:50 pm
I think the EPA approach is totally meaningless. It should be very simple. Here it is: (1) unlimited on first 40 miles from fully charged battery (1) 50 mpg when engine kicks in
September 26th, 2008 at 5:57 pm
#43 Gas Electric Volt:
This means with 40 miles electric range and 300 (?) miles gasoline range, you’re heavily weighting the overall mileage towards the gasoline-mode mileage. This does NOT reflect the equivalent miles-per-gallon that most drivers of the car will see in their daily driving. Not only is it unfair to the Volt, it’s not even accurate.
The best way to do it is this:
- For every “miles driven” you’re going to get a different overall mpg number, reflecting a different weighting of electric-mode and gasoline-mode mpg.
- Calculate this number (overall equivalent mpg) for every “amount of miles driven per day” from 1 up to, say, 300.
- Average all these numbers using a weighting factor according to the daily miles driven of American drivers. (In an earlier post, I called this a “distribution function” which will be familiar to any engineers/physicists here. EPA is calling it a “utility factor”.)
Yes, this involves a lot of math, but it’s all done behind the scenes by the EPA. The car buyer sees only a single “weighted-average equivalent daily mpg” number.
Of course, if you drive 300 miles a day, you’re going to see a much lower overall mpg (since most of your driving will be done in gasoline mode on the Volt). But it’s impossible to avoid this except by using THREE numbers instead of one to characterize the fuel economy of the vehicle.
September 26th, 2008 at 6:11 pm
#27 N Riley
I just turned down a chance to purchase a 2009 Toyota Prius that is due at the dealership by Oct 15th. Sticker price is going to be $29,155 plus taxes and fees. Leather seats, package group 3 and some stuff added that was ok, but things like $449 for XM Satellite Receiver Kit and complimentary XM service for 6 months. I don’t want Satellite Radio so that would be wasting my money. Plus a few other things they stick on most of us don’t want. I have been wanting to buy a Prius as a stop gap car, but have decided to wait a few more months to see what the Honda Insight hybrid is going to look like (price and features).
————————
I’m the same way. I’m not going to buy any ‘this gen’ Prius regardless, I think it is nice, but it is going to becomeo bsolete fast…all the new hybrids coming, and especially the next gen Prius announcements soon.
Funny, you mention the Insight, I attempted to go down to my local Honda dealer today and buy/order/put a deposit on one, sight unseen, he wouldn’t take my money…barely even knew about the car. The manager knew more…but all he would committ to is starting a makeshift list and putting my name on it. (Doesn’t sound to promising for this April 2009 release–and this was a monster dealership too).
I’ve pretty much conceeded I’m not getting a plug-in anything for a long time, and I want something to top up my ‘eco-smugness’ while I wait. I’m of course still getting the first 4 seat plug-in I can get from anyone…but this should give me something to look forward to short term.
So I’ll have a 3-4 year old Insight and a plug-in, in 2010…or 2011…or 2012. I figure might as well go for it now, it’s not like it will not have a 98% resale value if I don’t like it right? lol
I’ll keep you posted on the progess.
(=
September 26th, 2008 at 6:14 pm
It seems that there is an assumption that MPG in charge depleted mode (running of the ICE/genset) is 50mpg. This will again depend on the driving cycle and of course there will still be different figures for highway and city. This is why this isn’t so straightforward.
September 26th, 2008 at 6:23 pm
Composite numbers are not adequate. The need to state electric range and mpg after depletion to be more informative.
September 26th, 2008 at 6:34 pm
This is totally ridiculous.
It only makes sense for the following:
1. Display the miles per charge. (You can then compare battery sizes, and efficiencies.)
2. Display some type of efficiency rating on using the KW of the battery. (Factoring in regenerative braking) (Allowing you to see how well they use the available power.)
3. Display the MPG on the engine. (Compare to other cars, after the battery runs out.)
Using the EPA formula, the Tesla would get an infinite rating for its window sticker, since it does not use any GAS.
This would give the consumer a method of comparing different cars which will be coming.
So the tesla, could then be compared to the volt when using the batteries.
Providing one simple number for the masses is useless for everyone.
Hopefully, they smarten up to these issues before they release this single number.
September 26th, 2008 at 6:39 pm
Hey jefro 28.
Strip out the engine/generator? Don’t do it! An electric car club here in Silicon Valley have thought of this for YEARS and the answer has always been, “Can’t be done.” (!) I’ve never gotten a clear answer as to ‘why’ but it seems to be you can’t charge the battery while the electric motor is powering the car and/or the generator can’t power the motor with enough electricity to run at safe speed/performance levels. (i.e. 0-60 in two minutes or a top speed of 30mph, something like that.)
SO. What GM has managed to do is what the shade tree wizards in SILICON VALLEY have been unable to do. At least with hacking together components that are “off the shelf.”
The person who came up with the inverter for the Impact/EV1 DID build a tow along generator for an EV that did work so it could be done if you were an uber-genius but his company (AC Propulsion) never did follow it up. And of course a trailer with an ICE motor on it is nothing like a Volt which is an attractive, practical, four door sedan. For all of you wondering what a Volt would be like as a pure EV check out AC Propulsion’s Scion conversion. I’d pick the Volt over the all electric Scion. Just my opinion.
September 26th, 2008 at 6:44 pm
I propose 2 ratings, so we can compare the volt to competitive models.
First rating: Miles per Kw, battery only
Second rating: Miles per gallon after battery depleted
And a range estamate for battery only plus ICE assist range
September 26th, 2008 at 6:55 pm
27 N Riley: I just turned down a chance to purchase a 2009 Toyota Prius that is due at the dealership by Oct 15th. Sticker price is going to be $29,155 plus taxes and fees
And people were complaining about Prius prices killing Volt sales? For $10,000 more, the Volt would be worthy of consideration since they will likely all be quite well-equipped. Throw in a tax rebate of up to $7500, and the Volt would be a no-brainer.
If you’re thinking of buying a stopgap car, I wouldn’t… since the deprecation of a new car would pay for a lot of gas for your existing gas-guzzler.
September 26th, 2008 at 6:57 pm
Sticker:
40 MPC
50 MPG
Energy Star Rated!
September 26th, 2008 at 7:02 pm
The problem is the EPA is trying to approach this as if they were a big Bureaucracy! They’re trying to fit a square peg in a round hole (or a 120 plug into a 240 outlet). Their ratings are designed the old fashion way – for miles per gallon.
But for most drivers, most of the time, they will not use ANY gallons at all. So they need to admit that the Volt is the first of it’s kind, and they will need another way to inform the public for comparison.
I’m still open, but I like some of the simpler suggestions like Statik, Buddy P, Aspherical, jscott1000, plus…
Been on vac. Missed the site. But as I drove down interstate 77 thru Va., I couldn’t help think of being in the Volt, coasting down those long mountains, and arriving at the bottom with 10 or 20 extra miles of electric range! Ya!!!
=D~~~
September 26th, 2008 at 7:45 pm
There are no cars on the road where the EPA fuel economy rating is accurate to real world driving. Who drives 55 on the highway? That is the speed EPA uses for highway mileage. The volt will be no different. If the 75 MPH drivers get hold of a volt they won’t get 40 AEM either.
Take Care,
TED
September 26th, 2008 at 7:48 pm
GM shows EV1 and Volt together at the Alternative Energy and Transportation Expo in Santa Monica. Who knew they still had a functioning EV1 kicking around?
Couple direct links if anyone is interested.
http://gm.wieck.com/forms/gm/EV1ChevyVolt02.jpg?download=049238
http://gm.wieck.com/forms/gm/EV1ChevyVolt04.jpg?download=049236
http://gm.wieck.com/forms/gm/EV1ChevyVolt01.jpg?download=049239
September 26th, 2008 at 7:59 pm
And while we are at it. How come these weren’t part of the ‘oops, we accidently leaked some pictures, that just happened to be the executive’? These are much better than the pasty old white guy crew.
Molly Peck, National Advertising Manager
http://gm.wieck.com/forms/gm/X08CO_EX065.jpg?download=049127
Theresa Priebe, lead interior designer
http://gm.wieck.com/forms/gm/X08CO_EX073.jpg?download=049122
I’d much rather have these two telling me ’sweet nothings’ about the Volt that Wags and Lutz.
/non 56K modem file size warnings…high speed only, lol
September 26th, 2008 at 8:42 pm
It really doesn’t matter what the final EPA numbers are, as long as they are consistent between other models. It must take into account the amount of miles the car can go before the ICE fires up. That way the Volt would get a higher number than say a plug-in Prius that has only 1/2 the battery capacity (just an example – the specs have not been made public).
I have to say I like the idea of giving the consumer both values (before and after battery depletion). That way they can calculate their own more realistic numbers.
I think it’s going to be a complete re-education of the driving public. It’s going to take time and a lot of marketing dollars by manufactures but I think it will become second nature quickly.
I also like the idea of having cars available for week-long rental. This way the customer can see exactly what he/she is going to typically get. It might get drivers very excited to see they don’t need much gas at all! Most drivers that are concerned about their gas usage do not drive hard and crazy. Most will dive like grandmothers and get very good numbers.
September 26th, 2008 at 9:20 pm
Obviosly for all PHEV vehicles MPH value depending on the distance it covers, so EPA should have to re-look at its own rules.Other wise any decision of the EPA is likely to be questioned by other HEV makers.
September 26th, 2008 at 9:52 pm
#57 Statik
Look at the shine on that EV1, it looks like it probably has under 100 miles on it!
September 26th, 2008 at 9:53 pm
#58 Statik
Agreed, think how much better the response would’ve been had they leaked only those two pics.
September 26th, 2008 at 10:06 pm
George K # 55
“But as I drove down interstate 77 thru Va., I couldn’t help think of being in the Volt, coasting down those long mountains, and arriving at the bottom with 10 or 20 extra miles of electric range! Ya!!!”
*** *** ***
It’s known as the Walter Mitty-Volt syndrome. They think there will be a definite cure by 2010-2011.
September 26th, 2008 at 10:38 pm
that ev1 is the freaken ulgyest things i have ever seen i am so glad that i dont have to look at those things on the road. thanks hummer
September 26th, 2008 at 10:56 pm
#63 Grizzly
It’s known as the Walter Mitty-Volt syndrome. They think there will be a definite cure by 2010-2011.
Oh, ya!!!
September 26th, 2008 at 11:29 pm
The RATED mileage is already a pipe dream on every car sold today. I’ve seen the real-world mileage figures of a lot of cars and it’s never what’s on the sticker!
September 26th, 2008 at 11:34 pm
Would be nice if the stated mileage was derived from road testing.
Use increments of 50 miles.
50 mile drive = 200 mpg?
100 mile drive = 100 mpg?
150 mile drive = 75 mpg?
200 mile drive = 50 mpg?
The public needs to understand the first 40 miles are all electric.
Prius mileage is constant and fairly easy to compute. The Volt, and other cars in the future will produce astounding mileage figures if running on all-electric mode. The sticker should relay that message.
September 27th, 2008 at 12:24 am
canehdian #44:
I’m not sure what you are trying to say, but I think that the Volt ICE is said to use about 50 mpg, when it is on. That means (according to your figures):
55.2 total miles traveled, with 15.2 miles of them with the ICE on so
15.2 miles / (50 miles/gallon) = 0.304 gallons of fuel spent, giving
55.2 miles / (0.304 gallons) = 181.6 mpg
Not too shabby!
September 27th, 2008 at 12:40 am
Lyle asks “what does this mean to the consumer?”
The real question is “what does this mean to GM?”… the reason why is that for GM it means the higher the EPA MPG rating, the more high profit margin gas guzzlers they can sell and still meet the CAFE numbers. At 100mpg rating for the Volt, for each Volt they sell they could probably sell 3 Hummers.
Let’s also keep in mind that we’ve recently learned that the 40 miles/charge range for the Volt is based on a “city cycle”, would like to know what the range is (or will be) highway at 65mph?
The sticker should give two different sets of numbers… one set is the range in BEV mode, the other set should be in the “charge depleted” mode. As everyone should know by now the composite MPG with a series hybrid like the Volt is dependent on both the assumption that the vehicle is plugged in every night, and the average number of miles driven per day. A single set of numbers just doesn’t make any sense. Folks driving less than the BEV only range will use zero gas and that’s what’s important.
September 27th, 2008 at 2:16 am
I think the problem is that conveying what the Volt means to the average person looking at the EPA sticker is just going to be hard for a while.
If the person looking at the sticker hasn’t done alot of homework before looking at the car there is just too much information to convey to them in 10 seconds. And ANYTHING the EPA does to make the Volt’s numbers “comparable” to standard vehicles will fall short.
Because of the Volts configuration, moreso than ever your indivdual “mileage may vary” and thats going to require an explanation.
We all follow this car and other PHEV efforts so we know but I’m amazed at when I talk to people about the Volt how long it takes me to get through to them how it works. Most people just think “oh, like a Prius” but it’s just not that easy.
Don’t forget, we all quote the 40 Miles AER but thats likely just a city rating so even the AER is going to require explaining. I highly suspect that if I drive at freeway speeds that 40 is going to be some number less because faster travel is just less efficient.
September 27th, 2008 at 6:50 am
Just as a note, here is what GM proposed:
____________________________________
So if the Volt were to get, say, 50 miles a gallon while operating solely with its gasoline engine, the fuel economy rating would be 100 mpg.
Even so, that would be highly theoretical, much more so than for other cars. A Prius gets about 45 mpg in city driving no matter how far you drive it. The Volt’s fuel economy estimate would apply only in one specific scenario.
GM’s solution: Embrace the complexity.
A fuel economy window sticker proposed by GM in an April 2008, presentation to federal regulators shows fuel economy measured three ways: City and highway miles per gallon, city and highway miles per kilowatt hour and city and highway range (electric-only and total range.)
Assuming car shoppers know their local electrical rates, that information should allow them to judge how much the Volt would cost them to drive compared to other cars.
_______________________________
Here is the link:
http://money.cnn.com/2008/09/15/autos/volt_mileage_ratings/
So I beleive GM actually has the best solution, but apparently the EPA wants the consumer to be able to compare the Volt to other conventional vehicles.
September 27th, 2008 at 7:05 am
I agree that it really should list an AER range and an MPG for the ICE. That would make the most sense for the consumer.
But isn’t the real problem the CAFE standards? I think the reason they are trying to come up with a single number is so they can be used for the fleet average. Trying to figure in vehicles like the Volt must be giving them fits!
But do I really care what is on the sticker???? Except for the price, of course………..
Statik #58: You have violated just about every “politcal correctness” rule with that post!!!!! HAHAHAHAHAHAHAHA!
September 27th, 2008 at 7:15 am
Does anyone know if there is a chance to use CH4 for fueling this car?
September 27th, 2008 at 7:48 am
“Remember, first 40 miles, infinite mpg.”
———————-
40 mile (CITY ONLY), infinite mpg.
I want to know the estimated mpc when running at highway speed 65 mph (at least legally in most US states).
Can someone show me a video of an mule with the Volt power train running on pure battery at 65mph? (I know, how would I know if it was running of battery or ICE…). I am really wondering how developed the power train is.
September 27th, 2008 at 8:22 am
#73 Jim I
I agree that it really should list an AER range and an MPG for the ICE. That would make the most sense for the consumer.
But isn’t the real problem the CAFE standards? I think the reason they are trying to come up with a single number is so they can be used for the fleet average. Trying to figure in vehicles like the Volt must be giving them fits!
But do I really care what is on the sticker???? Except for the price, of course………..
Statik #58: You have violated just about every “politcal correctness” rule with that post!!!!! HAHAHAHAHAHAHAHA!
—————–
Political correctness? What is that? Too bad site analytics don’t tell you male-female breakdown of this site, that would be interesting. (Just a little light hearted jovial humoUr ladies…no offense).
Speaking of the CAFE standards, I wouldn’t even try to calculate the Volt into them. I would just give GM vehicle credits, like sell a Volt –dropped two other vehicles out of your fleet CAFE calculation (*cough* trucks *cough*)….or something of that nature.
September 27th, 2008 at 8:39 am
A simple plan is to give a number for mpg as obtained over the first 200 miles, starting with a full gas tank, full charge, full whatever. Doing that has a multitude of advantages –
It’s simple. Ordinary people can understand it quickly.
It can be applied to all vehicles.
It gives an incentive to do better.
The first 200 miles is roughly a week’s driving for many people, so it is an understandable number of gallons for an understandable distance.
Posts above advocate using 2 numbers. That is not a good thing to do. Most people will not understand these numbers. Most cars will have zero for AER. So people will look at the Volt and say that its performance is other number, and doing that will place the Volt at a disadvantage.
I realize that people here want numbers that give more detail. That can be added in the fine print at the bottom, or on another sticker, or whatever. Most people find more detail just more confusion. They like the present system, which is set up to allow people to compare cars with one number, as a starting point, using a system that applies to all cars. Mpg over the first 200 miles does that.
September 27th, 2008 at 8:40 am
From Statik @#6:
What is so bloody hard about this… those stickers aren’t slapped on all those cars to help the manufacturer sell them… they are there to inform the customer in the most reliable way…
_______________________________________________
Maybe in Canada my friend, but this is the USA. I’m afraid that the lines between government and business are blurred too easily and too often on this side of the border. It is easy for most Americans to recognize when government sticks its nose too far into the private sector. Unfortunately, most here would view what you call common-sense as excessive government interference. Here, putting an “organic” label on a can of soup is often nothing more (or less) than a feat of persistant lobbying by large food corporations.
September 27th, 2008 at 8:43 am
#67 avatar Says: “The public needs to understand the first 40 miles are all electric. Prius mileage is constant and fairly easy to compute. The Volt, and other cars in the future will produce astounding mileage figures if running on all-electric mode. The sticker should relay that message.”
————————————————————————————–
I think most people will understand when you tell them that the first 40 miles are all electric. That’s pretty easy.
What most people won’t understand is how much gas this will actually save them over other plug-in cars. If a Plug-In Prius gets 150 MPG for the first 17 miles, how does that really compare with the Volt? Specifically, how will the EPA rate the MPG for the Plug-in Prius vs. the Volt.
Toyota will have a Plug-In Prius model out around the same time as the Volt. The Plug-In Prius will be essentially the same as the regular Prius, except the NiMH battery will be replaced with a Li/Ion of the same physical size, and there will be a plug-in charger port. Switching to Li/Ion will double the electrical storage, yielding an 8-mile all-electric range. But with the Prius, as soon as you step on the gas, or if you go 65 MPH or more on the highway, the gas engine will come on. There really is no all-electric range. So instead, these cars are currently advertised as 100+ MPG.
Using a typical yearly driving pattern from post #8, the Prius Plugin will get an average of 70 MPG. The Volt will get 314 MPG.
September 27th, 2008 at 8:48 am
Lyle’s title for this thread includes a question, “Calculating the Volts EPA Rating, More than 100 mpg?”
My answer is that 100 mpg excessively UNDERSTATES the Volt’s actual equivalent mileage capability for the vast majority of buyers. However, I agree that it’s important to quote a single number (and state it in mpg to allow quick direct comparison to all other cars). The reason is an average car buyer will devote only 1-2 min to reading the window sticker, so it MUST quickly convey a single mpg. Also, most people grasp and remember simple NUMERICAL EXAMPLES, not detailed explanations.
Considering this, my suggestion for the Volt’s window sticker content is…..
============================================================================
Approx 4 out of 5 (78%) of all US daily trips are <40 miles/day. For these trips, this vehicle’s equivalent EPA gasoline mileage is*….
150 MPG …….[(40mi / 8KWHx10cents/kwh) x 300cents]*
*10cents/KWH is well ABOVE the off-peak rate for over-night charging and $3.00/gal is well BELOW the cost of regular gasoline in most areas of the US, therefore 150 MPG is LESS THAN what most owners can expect.
============================================================================
Below this on the window sticker trip mileage examples can be shown….
“For approx 1/5th (22%) of all trips exceeding 40 miles/day**….
60 miles/day: 90 MPG (0.27 gal + 20mi at 50mpg = 0.67 gal per 60 mi = 89.55mpg)
80 miles/day: 75 MPG (0.27 gal + 40mi at 50mpg = 1.07 gal per 80 mi = 74.77mpg)
100 miles/day: 68 MPG (0.27 gal + 60mi at 50mpg = 1.47 gal per 100 mi = 68.03mpg)
200 miles/day: 58 MPG (0.27 gal + 160mi at 50mpg = 3.47 gal per 200 mi = 57.64mpg)
300 miles/day: 55 MPG (0.27 gal + 260 mi at 50mpg = 5.47 gal per 300 mi = 54.84mpg)
**For trips of 60 to 300 miles it is assumed that the cost of gasoline is $3.00/gallon, that NO gasoline is needed for the first 40 miles and that ONLY gasoline (no electricity) is needed for the remainder of each trip distance shown above
=======================================
=====================================
The above table(s) present the Volt’s mileage in a simple yet comprehensive way.
September 27th, 2008 at 9:02 am
An interesting artical posted on the 26th from the Calgary Herald speaking to how Aggressive Driving and Air Conditioning could cut mileage range estimates for the electric car.
http://www.canada.com/calgaryherald/cars/story.html?id=719bbee4-b52a-4e4b-a579-6cfb9353e985
September 27th, 2008 at 9:05 am
The rating system with a utility factor proposed by Mike Duoba/SAE seems to be the best proposal for evaluating millage for an E REV that I have heard yet.
I have a slightly wacky solution that of course won’t fly but makes sense for all vehicles in the long run. This would be to adopt the European convention l per 100 km as opposed to mpg. You could run the Volt and all other cars through a slighly longer US driving cicle and do gallons per 100miles. This is important because it turns out that mpg actually gives people a false perspective (Increasing efficiency on poor millage vehicles is saving more fuel. More fuel is saved moving from 20 to 25 mpg than from 35-50 and from 12 to 14 mpg saves even more than both) on efficiency and individuals tend to choose more optimal choices if millage is depicted in fuel per a given distance. Anyway if you haven’t seen this article (The Miles per Gallon Illusion) I think most folks here would be interested to read it. If some of you have wondered why GM started there full hybrid program with full size SUVs this is why (still doesn’t make sense from a marketing perspective but it’s why they did it).
Since most people will not have access to the article here is a link for a video by the authors describing their research and findings.
http://www.youtube.com/watch?v=K2XSuw02vKA
‘The MPG Illusion’ Richard P. Larrick* and Jack B. Soll
Science 20 June 2008: Vol. 320. no. 5883, pp. 1593 – 1594
September 27th, 2008 at 9:06 am
We need a new number for all cars: An EPA Efficiency Rating
Using the 40 Miles Per Charge / 50 Miles Per Gallon numbers mixes units. MPG is a measure of efficiency. Miles Per Charge is not a measure of efficiency because it doesn’t take into consideration the size of the battery. It needs to be Miles per kWh. Using MPC is the same as stating what the Miles per Tank are for a gas car.
Say GM makes a Plug in Hummer with a 320KwH pack. It gets 80 MPC. “Wow! That’s twice as good as the Volt!”… but it’s only 1/10 the efficiency. The EPA window numbers can’t be based on range.
An Efficiency Rating can be weighted however the EPA sees fit. Maybe Miles Per Joule or some unitless number so they can weigh each fuel source based on it’s environmental cleanliness. They can even provide a chart that has different driving habits so you can look up your personal annual estimated fuel cost for different vehicle efficiencies.
September 27th, 2008 at 9:35 am
Whenever the sticker issue is raised we always end up talking about it from a consumer issue. For GM the more important issue is CAFE.
Certainly a sticker with 100 mpg isn’t a bad thing for GM but you’re not going to see consumers walk into a showroom knowing nothing about the Volt and buying a $40K compact because of the sticker. Sales will be driven by sales and marketing. A message such as “If you are are like 80% of Americans you will never use a drop of fuel” is more powerful than “100 mpg.”
September 27th, 2008 at 1:11 pm
The Volt electric range will be all over the place.
[quote]The goal is to promise drivers of a lithium ion battery-equipped electric hybrid vehicle a 64-kilometre range on one charge, but that may be a gross exaggeration, he said. [/quote]
How the car is driven and accessories used will have a big impact on the electric portion of the drive.
[Aggressive driving -- faster acceleration and driving at faster speeds -- may cut that range to between 45 and 51 kilometres. Using the air conditioning may reduce the vehicle's range to around 24 to 32 kilometres, he said. In response, the vehicle's gas-powered engine will kick in two or three times during an excursion, which actually is a cost-effective response and will help extend the life of the battery, he said.[/quote]
Need to keep doing the hypermiling techniques since they will still be necessary even if driving the Volt.
September 27th, 2008 at 1:19 pm
Stating miles per gallon on an electric car is as dumb as gallons of fuel oil per hour in my wood stove.
Kilowatt hours per mile for the first 40 miles after charging, miles per gallon for over 40 miles after charging.
If electric cars are to be compared, then KWH/mile is a necessary figure.
September 27th, 2008 at 1:26 pm
The Volt electric range will be all over the place.
How the car is driven and accessories used will have a big impact on the electric portion of the drive.
http://www.canada.com/calgaryherald/cars/story.html?id=719bbee4-b52a-4e4b-a579-6cfb9353e985
Need to keep doing the hypermiling techniques since they will still be necessary even if driving the Volt.
Sorry for the double post. The website said I didn’t have permission to edit my posting…
September 27th, 2008 at 9:05 pm
Some comments from CARB
http://www.detnews.com/apps/pbcs.dll/article?AID=/20080927/AUTO01/809270368/1148/&source=nletter-business
September 28th, 2008 at 10:41 am
#86 Storm Says: “If electric cars are to be compared, then KWH/mile is a necessary figure.”
————————————————————————————–
Yes, KWH per 100 miles needs to be listed for comparing EVs.
But what if I’m comparing a Volt to a Plug-In Prius? The Plug-In Prius doesn’t really have all-electric range, so they advertise in terms of MPG. Same thing with a Saturn Vue Plug-In.
Or what about comparing a Volt with a regular car, like a Honda Civic?
So as I’ve said many times, you need all the detailed info, but the average combined MPG should be the most prominent, like this:
• Average combined mileage (MPG)
• Electric Range (miles city/hwy)
• Mileage During Electric Range (MPG city/hwy)
• Mileage After Electric Range (MPG city/hwy)
• Electric Energy Use (KWH/100miles city/hwy)
This rating system would allow ALL types of plug-ins to be compared with each other and with regular cars.
September 28th, 2008 at 10:45 am
The Average combined mileage would be calculated by the EPA using a typical driving pattern for a year. Assuming a single charge per day (usually at night), the typical pattern might be:
• 30 days at 8 miles per day
• 50 days at 16 miles per day
• 240 days at 30 miles per day
• 30 days at 60 miles per day
• 3 days at 450 miles per day
The exact numbers may vary, but the point is that this type of driving pattern could be used by the EPA to estimate the average MPG of all plug-in vehicles on a level playing field.
I’ve created a quick spread sheet using the typical driving pattern example above in order to give a rough idea of what this might look like for the 4 plug-in cars coming out in 2010. Obviously, these are preliminary estimates which will change as these vehicles get closer to production, but it gives an idea of what I’m suggesting.
Saturn Vue plug-in
• Average combined mileage (MPG): 50
• Electric Range (miles city/hwy): 17/14
• Mileage During Electric Range (MPG city/hwy): 148/132
• Mileage After Electric Range (MPG city/hwy): 34/32
• Electric Energy Use (KWH/100miles city/hwy): 25/30
Toyota Prius plug-in
• Average combined mileage (MPG): 70
• Electric Range (miles city/hwy): 17/15
• Mileage During Electric Range (MPG city/hwy): 154/138
• Mileage After Electric Range (MPG city/hwy): 48/45
• Electric Energy Use (KWH/100miles city/hwy): 17/19
Chevy Volt
• Average combined mileage (MPG): 314
• Electric Range (miles city/hwy): 42/38
• Mileage During Electric Range (MPG city/hwy): ∞/∞ (All Electric)
• Mileage After Electric Range (MPG city/hwy): 52/48
• Electric Energy Use (KWH/100miles city/hwy): 18/22
Fiskar Karma
• Average combined mileage (MPG): 340
• Electric Range (miles city/hwy): 52/48
• Mileage During Electric Range (MPG city/hwy): ∞/∞ (All Electric)
• Mileage After Electric Range (MPG city/hwy): 46/43
• Electric Energy Use (KWH/100miles city/hwy): 18/22
September 29th, 2008 at 12:25 am
The EPA looses any credibility by publishing a simple-minded number like “100 MPG” for the Volt, or any EV.
“Tits on a Bull” anyone?
September 29th, 2008 at 7:57 am
I know it’s small beans compared to GM’s normal cash flow, but the 100 mpg threshold would also entitle them to an automatic payout of the $25 Million “X-prize”.
http://www.xprize.org/news/automotive-x-prize-seeks-100-mpg-car
To put it in other terms, $25 Million in cash is the equivalent of selling 25,000 cars and making a $1,000 clean profit per vehicle. A little bit of negotiating and arguing is a small price to pay for that icing on the cake, although it clearly isn’t their motive.
September 29th, 2008 at 9:36 am
#6 Statik
I agree.
40 AER – 50mpg
I disagree.
If the goal is to sell the Volt primarily to the quantitatively oriented, the above formulation is ideal. These people will learn what AER means, it will be able to draw the inference, while still looking at the sticker, that they will not burn gas during the next 40 miles. Some of them will be aware that the electricity they do use will cost a lot less than gas. They will intuitively develop a blended average of battery and gas costs, and conclue that the Volt offers extraordinary energy economy.
While people who think this way dominate this board, they probably account for 1-2% of the population,
If the goal is to make the Volt a mass market car, the above formulation would be a problem. The public makes decisions with about as much mathematical rigor as Paris Hilton does. So faced wth a sticker that says:
40AER/ 50mpg
The typical consumer will say: 50 mpg? That is only 7 mpg better than the Prius, and it costs more. Plus you have to deal with plugging it in, I think I will just go with the Prius.
The way to really sell this is to develop an equivilent mpg rating that in one number, captures gas use, electricity use, electricy cost, and typical driving habits. That way, you will see
Volt 100 mpg
Prius 43 mpg
Gee, the Volt costs more, but you get 57 miles per gallon for your extra money. Do you have it in green?
September 29th, 2008 at 12:03 pm
BluesBrian Says:
September 29th, 2008 at 12:25 am
The EPA looses any credibility by publishing a simple-minded number like “100 MPG” for the Volt, or any EV.
“Tits on a Bull” anyone?
The Volt is revolutionary technology, so it shows a revolutionary mpg rating. There is no reason this should lose it credibility. It really is more than twice as energy efficient as the Prius, and the numbers need to show that.
We (and the EPA) need to think out of the box, and come up with an mpg-evquivilent rating which is comparable with the mpg rating of gas cars, and captures the true energy usage based on the way the cars are actually driven by consumers.
September 29th, 2008 at 12:11 pm
If you come up with some bogus / twisted way to calc EPA mileage, it will be the death of the electric car.
Consumer will complain, word will get out, and sales will stagnate.
GM knows of bad public reputation and how quickly sales will stop ….corvair, vega, olds diesel, quad 4 , fiearo, turbo 200, Grand National Buick
October 1st, 2008 at 12:09 pm
I agree with Kyle above. The whole thing would be a lot easier if you Americans used the L/100Km unit (or Gallons/100Miles if you must) like the rest of the world.
A more honest metric, however, would be $/100Miles, which would include the cost of electricity. Even more honest would be $/3years, which includes maintenance. But what people really want to know is purchase price + $/3years.
Regardless of the unit, the Volt and other PIHVs will look good.
October 6th, 2008 at 7:36 pm
don’t buy an american make car, they don’t last as long as japanese, therefore brake down sooner and become garbage for the earth.
jap cars = good for environment
u.s. cars = bad bad bad
October 13th, 2008 at 9:48 am
The incredible and astonishing thing about regenerative braking is not so much the power it recovers, but
THE BRAKE PAD WEAR IT PREVENTS!
When scanning the processor of my neighbor’s 2001 Prius, which had 113,000 miles on it at the time, as I was analyzing the systems waveforms (which is what I teach to auto techs), and I repeatedly asked how many miles he had on it. ( I hadn’t seen the odometer).
He repeated 3 times to my skeptical 3 questions of how many miles it had on it all during the 45 minute scan.
When I got out to inspect the pads, THEY STILL HAD 30 TO 40 PERCENT PAD LEFT on the originals! How many front brake jobs would have been needed? 2 front brake jobs and probably a rear brake job as well. THESE ARE THE SORTS OF TERRIFIC THINGS THAT ALL THE NEW ENGINEERING WILL BRING TO THE CONSUMER.
(Yes there will likely be more fuel system cleanings if “TOP TIER” fuels are not used by owners.)
Note: I have always used “TOP TIER” fuels in my motorhome (which I am selling to make way to buy a Volt), and, the fuel has never gone stale the twice-a-year I fill up the tank in it.
(Shell 87, if I am allowed to say so).
Dan Petit, Austin, TX
October 13th, 2008 at 3:27 pm
[...] John. GM-VOLT : Chevy Volt Electric Car Site
December 24th, 2008 at 4:42 pm
The correct EPA rating is now in number of kW-hr/100 miles (that’s number of kilowatt hours per 100 miles.
The lower the number, the more efficient the vehicle is. The Tesla Roadster, for example, is EPA rated at City: 32kW-hr/100 miles, Hwy: 33kW-hr/100miles. My Zero X motorcycle (full electric) averages 2kW-hr/100 miles in real world driving (7,000 miles street riding, so far, with zero maintenance). That means that my Zero X motorcycle is more than 16 times more efficient than a Tesla Roadster.
Here’s my best guess at the Chevy Volt EPA rating using power pack only, with the propsed 16 kW power pack and a 40 real world mile range. To maximize power pack life, using a lithium ion base, and being extra cautious, the power pack would never exceed 80% (also makes the recharging faster) and never go below 40% (real world indicates that a 20% to 100% range, managed extremely rigorously, would be possible with about the same power pack life span), which means thaht 40 miles would use 40% (80% minus 40%) of the power pack capacity (16kW).
Now consider that 100 miles is 2.5 times 40 miles.
The calculation: (16kW-hr times 40% times 2.5) divided by (40 miles times 2.5) = (16*0.40*2.5) kW-hr/ (40*2.5) miles = 16Kw-hr/100 miles
This means that the Chevy Volt, with a propsed curb weight 800 pounds heavier than the Tesla Roadster, using more conservative power pack management, would be twice as efficient than the Tesla Roadster, which I doubt. This tells me that GM is confident enough in the battery performance, after their extreme testing of two manufacturers, that they are using the most agressive power management possible (probably 20% to 100%, which equals 80% of power pack capacity), in which case the calculation becomes:
(16kW-hr times 80% times 2.5) divided by (40 miles times 2.5) = (16*0.80*2.5) kW-hr/ (40*2.5) miles = 32Kw-hr/100 miles
This matches the Tesla Roadster efficiency exactly, though the CHevy Volts looks to have a higher curb weight by 800 pounds. The difference – probably in improved battery performance from 2008 (the 2008 Tesla Roadster EPA ratings date) to 2010 expectations for the CHevy Volt release.
It wouldn’t surprise me if, based on this, that Tesla is already capable of getting below 30kW-hr/100 miles from their latest power packs, on the weight difference.
I think my work is reasonable based on the final results, but if someone else can improve on it, please chime in.
Note: This is the correct metric for series hybrids, such as the Chevy Volt. For parallel hybrids the gas fueled portion can be converted from miles per gallon to the new metric kW-hr/100 miles and each portion averaged, weighted by miles for a combined result of a single number in kW-hr/100 miles.
December 24th, 2008 at 4:54 pm
Dave G had it best, but Dave’s and my numbers don’t match and he has everything being far more efficient that the Tesla Roadster on kWh/100 miles, which I highly doubt. The difference is probably in how conservative the power pack management estimate is, as I can’t imagine that the Prius et. al. don’t use electric motors that are twice as efficient at the Tesla Roadsters (indeed, I’m pretty sure that’s not possible, with the already extremely high efifciency of existing electric motors). Dave G seems to be assuming a 40% of capacity usage (40% to 80% range), which is in line with existing nickel power packs in most current hybrids and some electrics. But I distrust the results using that. Again, consider that a Tesla Roadster is already EPA rated at 32.5 kW-hr / 100 miles mixed city/hwy.
Can someone resolve this difference with Dave G’s results?
December 24th, 2008 at 4:55 pm
Remember, the lower the number of kW-hr/100 miles, the more efficient the vehicle.