JRP3
Hyperactive Member
Your descriptive sentence works just as well with a plug in hybrid or PHEV40 label. "It's a plug in hybrid that can go about 40 miles on electricity alone." Simple, concise, accurate.
-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
Pure BEV Dogma
- Thread starter bonnie
- Start date
....and leaves out the distinguishing operating characteristics that are important to drivers who prefer electric drive...
JRP3
Hyperactive Member
You mean it does something more than travel about 40 miles on electricity alone? What else can it do that someone who prefers electric drive should be aware of?
It's about what it doesn't do during those 40-some miles -- it doesn't start the engine where other PHEVs might. That's an important distinction, right?
JRP3
Hyperactive Member
The important distinction is the over all EV range, the various specific details about how each PHEV handles the ICE management during the electric range simply can't be handled by a single phrase or acronym, not even a new one. REEV, EREV, etc., provide no useful data. Coming up with a bunch of unfamiliar terms does nothing to clarify it without further explanation to the uninitiated. Plus actual behavior is usage dependent. Short range city driving the PHEV Prius can operate only in EV mode I believe, same is true of the Ford, but with a longer range. I also believe that if it's cold enough the Volt will start the ICE even if the pack is not depleted. Plus can't you manually select a "charge extending" mode and engage the ICE if you wish? I think anyone seriously considering the vehicles will do the basic research into how they actually operate. The real concern is avoiding the mess GM created with it's marketing, and that Bob Lutz is perpetuating.
BEVx is an EREV is a PHEV is an HEV and to me there's a siginificant division in terms of EV between EREV and PHEV, since EREV requires the same level of motor and inverter capability of an equivalent BEV.
You can select Hold in the Volt because it was dumb not to be able to. Hold is a range extension mode.. However, note that the Volt does not have a "blend" mode as found in the Energi and PiP.
You are right, I would not buy a 40 mile EV. I did not buy the Volt for its ICE however, as (almost) every car has one of those. What is different about the Volt is that it has EV capabilities also. That is why I bought it.
You and I are looking at the same thing (the Volt). We both completely understand it. However we are looking from different viewpoints, so we see it differently. Nothing wrong with that, it is just human nature.
GSP
Umm, but that's the whole point of the EREV acronym. It's a new label to identify plugin hybrids that can operate without unusual limitations while using only an electric drivetrain until the battery runs out. You can try to assert that it's meaningless but that's what it means according to GM and I think it communicates something useful and important.
Nobody claims the Prius Plugin or the Ford Energi are EREVs.
If it's under 15F, the engine will start occasionally to help generate waste heat. That's an asterisk-level issue. I've owned my Volt for just over 3 years and 69,000 miles and I've never had the engine start because of cold temperatures in coastal California. Even in colder climates in winter, that condition will often not be met during daytime driving and when it happens it's only occasionally during a few months in colder climates. When it happens, the engine runs only intermittently. It's not a routine limitation during typical driving conditions in many geographical areas.
Yes, but who cares? You are searching around desperately for a reason why EREV is somehow not a meaningful or useful term. Give it up already.... EREV communicates a useful idea in a single acronym. It communicates that the gas engine stays off when there is charge left in the battery except under extreme conditions (like those where Model S brake calipers are freezing up).
stopcrazypp
Well-Known Member
"Hold" or CS mode in the Volt IS a "blend" mode, just like the Energi and PiP! In this mode, above 70mph, the ICE has a mechanical path to the wheels:
http://www.motortrend.com/features/editorial/1010_unbolting_the_chevy_volt_to_see_how_it_ticks/
- - - Updated - - -
Isn't that the issue? If you have to make exceptions for road conditions (cold weather and mountain/hold mode) isn't acceleration just one part of it? And with newer cars like the Energi (which Ford doesn't bother to try to sell as an "EREV"), you can keep the ICE off even during acceleration using the EV mode and the EV top speed is 85mph. I think the only car that can satisfy the EREV definition with no exceptions is ironically the i3 REx.
I think that ItsNotAboutTheMoney was not referring to the series-parallel split power path from the engine to the wheels that the Prius, Ford hybrids, Volt, and several other HEVs have.
The Ford PHEVs have a Charge Depleting mode that runs the ICE, "blending" energy from gasoline with energy from the plug. This provides max energy efficiency, and does run the engine less than a non plug-in HEV, but is not an EV driving experience (so it sucks, in my opinion). I think they also have a driver selectable "EV mode" that doesn't run the ICE in CD mode, like the Volt.
GSP
PS. Since this is the "picky terminology thread," it is worth noting that the i3 is not just an EREV, but a subset of EREVs that "The Air Resources Board" (CARB) labels BEVx. Only CARB makes it more confusing by classifying BEVx as a subset of BEVs, even though BEVx's clearly are hybrids per the official SAE definition.
Also, GM is fostering more confusion by referring to the ELR as an EREV, even though it does not meet their own definition of EREV (a subset of PHEVs).
Last edited:
JRP3
Hyperactive Member
How can you not see the contradiction in your statements? Simply put, the Volt needed to have both electric drive and an ICE for you to purchase it. Missing either you would not have bought it.
I think there is something wrong with it, I'm seeing the entire picture and you're ignoring half of it. Volt owners seem to suffer from "ICE blindness".
Yet we have real world examples where it only causes confusion: http://www.thetruthaboutcars.com/2012/02/fox-tests-volt-runs-out-of-juice-in-lincoln-tunnel/
And no one has tried to pretend they can run out of charge an leave you stranded, because they have been purposely and accurately marketed as plug in hybrids, unlike the Volt.
That's the point, it doesn't really matter what the minute distinction is between the operational modes of different plug in hybrid vehicles, except apparently to some Volt owners. EREV communicates nothing to those who don't already know, and those who do know it's a plug in hybrid that can go about 40 miles on electricity. I have no idea what your Model S reference has to do with anything.
Note, BMW is marketing their i8 as a plug in hybrid.
http://www.bmwusa.com/Standard/Content/AllBMWs/ConceptVehicles/i8/
Yes, blending is a CD thing and Prius fanbois consider it a virtue.
The Energi special EV mode is called EV Now and it's not a default mode, IIRC. It also limits power to 118hp and that particularly affects higher-speed acceleration.
- - - Updated - - -
Because the i8 is a plug-in hybrid. Floor the gas pedal and it'll run the engine for performance.
When my wife first took our Prius to work, a colleague asked if she plugged it in. Ignorance is everywhere. When I'm talking to people about the Volt I'll use PHEV or EREV depending on what I'm trying to convey and how much time I have.
According to Wikipedia, EV power maxes out at 68 kW which is about 91 hp. Energi owners on forums sites have said that acceleration is good in EVNow mode on city streets but is weak at highway speed and is likely inadequate for passing. In any case, the default mode is not EVNow so the engine will be started during brisk acceleration, especially at or near highway speeds or when climbing hills or other steeply graded roads. I have not driven an Energi model so I can't give my own subjective impressions.
- - - Updated - - -
Huh? How so? The ELR is just a Volt with less conservative software controls, a new body shell, and lots of fancy interior materials and accessories. I'm not aware that it's EREV-ness is any different.
- - - Updated - - -
The "70 mph" is a bad Internet meme. In reality, the Volt frequently engages the mechanical path from the ICE to the wheels at speeds as low as 36-40 mph. In any case, the point of EREV is to keep the engine off so this is an irrelevant side issue.
Ford doesn't claim the Energi is an EREV so why are we talking about it?
The EREV exceptions for the Volt are rare and obscure for many owners. For owners in the coldest winter areas, the exceptions last only part of the year and at a time when the practical performance and usage of BEVs are also constrained and limited by typical driving conditions. Optional driving mode buttons are irrelevant -- if you push a button that purposefully starts the engine ("Hold mode") that shouldn't detract from whether the default operation of the car complies with EREV.
Non-EREV cars may start the gas engine at all times of the year in their default driving mode under common and typical driving conditions or have unusually limited capabilities in an optional "EV now" mode.
- - - Updated - - -
LOL. That's ultimately linking to a FAUX News video featuring Eric Bolling. His ideological clown routine had nothing to do with whether EREV communicates a useful vehicle characteristic.
Last edited:
JRP3
Hyperactive Member
It has everything to do with the fact that had it been marketed as the plug in hybrid which it is, nonsense like that, and like calling the Volt a $40,000 EV with only 40 miles of range, never could have happened. EREV communicates nothing useful since there are always further descriptions and caveats needed, and what you consider to qualify as "EREV" someone else may not, and vise versa, since it's not a real term. You claim the Ford is not an "EREV" since it doesn't meet your definition, which seems only to apply to the Volt, and maybe the ELR I guess. Just look at all your arguments as to why one vehicle is an EREV but another is not. The hair splitting is subjective. Enthusiasts can argue the details but it only fosters confusion amongst the general public.
LOL. Faux News. Eric Bolling. Of course it would have happened with little if any change to "the script". However, I certainly won't deny that GM flubbed much of their Volt marketing effort. Obviously, I think "EREV" is fine but the silly avoidance of "hybrid" and PHEV was a mistake along with the poorly communicated story around the planetary gear transmission.
I guess "hair splitting" is subjective. I don't see it that way. Ford doesn't claim the Energi is EREV so I don't think there is any confusion or dispute about that. EREV or not EREV is largely, although not entirely, about battery power output which is itself closely associated with range capacity and physical pack size and cost. As batteries improve and future PHEVs come out with higher capacity batteries I think EREV cars will become more common. If you have enough battery power there isn't much point in starting up and blending in the ICE when there is still juice left in the pack.
JRP3
Hyperactive Member
I agree that future plug in hybrids will have more battery only range and performance, and that logical progression nullifies any need to create a new label for them. The Volt/Ampera really does seem to be the best of the current crop, the i3 could have been but it's crippled by poor styling, an ICE that seems only to provide something of a limp home mode so it's not a great hybrid, and too limited range in it's pure EV form so it doesn't advance EV technology.
The i3's REx is intentionally limited. The BEVx classification intends that the range extender is rarely used and the limited caoability allowed BMW to use a small, efficient engine. The i3 is providing what many PEV enthusiasts have been wanting.
Hair splitting for sure.
The fact is that batteries are expensive and in today's market, it makes a lot of sense to have a gas engine backup a smallish battery. The Volt does this. The Ford products are really less "EV" because they need an ICE for everyday driving. That is why the Volt is different. Sure, you can go EV only with a Ford but most won't. Whereas with a Volt, almost everyone is driving pure EV until the battery runs down. That is a pretty important distinction.
The Volt is also superior because it was designed ground up as a EV with ICE backup. The Ford products are available in non plug in forms and the batteries for the plug in kill the cargo area. The batteries are also not centrally located near the floor as the Volt is. The fact is the Volt shares just a few more characteristics with a pure EV than the Ford products.
The PIP is even less "electrified" and in the world of plug in's is not even close to an EV.
There is a hierarchy and ignoring the Volt's position and saying it is comparable to a PIP is dishonest.
The biggest problems with the Volt are that it is a Chevy and it is quite small. The 2 reasons that I didn't buy one.
I can't believe I am defending the Volt but it was a more significant step than the Ford products which incidentally get pretty bad hybrid gas mileage.
The fact is that batteries are expensive and in today's market, it makes a lot of sense to have a gas engine backup a smallish battery. The Volt does this. The Ford products are really less "EV" because they need an ICE for everyday driving. That is why the Volt is different. Sure, you can go EV only with a Ford but most won't. Whereas with a Volt, almost everyone is driving pure EV until the battery runs down. That is a pretty important distinction.
The Volt is also superior because it was designed ground up as a EV with ICE backup. The Ford products are available in non plug in forms and the batteries for the plug in kill the cargo area. The batteries are also not centrally located near the floor as the Volt is. The fact is the Volt shares just a few more characteristics with a pure EV than the Ford products.
The PIP is even less "electrified" and in the world of plug in's is not even close to an EV.
There is a hierarchy and ignoring the Volt's position and saying it is comparable to a PIP is dishonest.
The biggest problems with the Volt are that it is a Chevy and it is quite small. The 2 reasons that I didn't buy one.
I can't believe I am defending the Volt but it was a more significant step than the Ford products which incidentally get pretty bad hybrid gas mileage.
stopcrazypp
Well-Known Member
The ELR is not an EREV because it does not get "full performance" with the ICE off (0-60 time is lower). The Fisker is also not an EREV for the same reason (0-60 and top speed is lower in EV mode).
GM's definition (as opposed to colloquial definitions which vary depending on who you ask) has the following two criteria:
It must be a "full-performance" EV when the ICE is off.
The ICE must never turn on until the battery is depleted.
http://www.media.gm.com/content/dam/Media/microsites/product/volt/docs/paper.pdf
The i3 REx is the only car that meets both criteria with no exceptions (and it makes sense given it started as a BEV with the "range extender" added afterwards). The Volt satisfies the first but not the second (unless you ignore exceptions).
Originally GM's definition was much simpler: EREV = series PHEV, but they couldn't use that definition after they changed the Volt's design.
So as long as they have the default on "EV now" it's automatically an EREV by your definition?
Last edited:
That's true for a Volt as well -- performance is a bit better at speeds above 45 mph or so in hybrid mode with the engine running. So?
Nothing in GM's SAE paper that you linked to states any requirements about EREV behavior after the battery runs out of grid charge and the engine starts up. This EREV requirement of yours does not come from GM or this SAE paper that you link to.
The paper's definition of "full performance" in EV driving is not relative to the performance of the vehicle in it's later extended range phase.
Here's is the paper's definition of "full performance":
That definition is about fully capable drivability and performance and is ultimately relative to other competitive vehicles in the same class ($20-$40k compact sedans or hatchbacks, for example).
While the goal is clearly to avoid starting the engine while charge remains in the battery, the paper's more specific definition is relative to general PHEV's needing to start the engine during EPA test cycles (and beyond those power requirements during typical use of the vehicle):
I think it's self-apparent that GM's definition of EREV was meant to be inclusive of the Volt.
We haven't seen all the details of the i3's range extension behavior yet but it's a certainty that the engine will start up occasionally for maintenance purposes (lubrication, burn off stale fuel, etc.) before the battery is depleted. I guess you aren't counting that exception. The only presumably remaining difference from the i3 is the Volt's behavior of occasionally running the engine at temperatures under 15F (-10C) to use the waste heat to assist in cabin heating.
GM showed off the concept Volt at the Detroit Auto Show in January 2007 and committed to build it by the end of 2007. This SAE paper was published in 2008. The non-seriesness of the Volt's range extender was first revealed in September 2010.
Do you have a link to GM's "original definition" that required that "EREV = series PHEV"? Even if you do, I'm not sure it's more than a footnote-worthy historical artifact and I doubt it was more formal than this 2008 SAE paper.
In any case, I've never been clear why anyone cares whether a hybrid is series-only or is capable of series/parallel operation as long as it does not detract from the driving experience. It is possible to notice the parallel-to-serial transition in a Volt in extended range operation if you suddenly slam the accelerator at speeds above 40 mph (I haven't noticed the transition in many months of recent driving). Other than that, the power is seamless and there is no sensation of gear shifting etc. as in a conventional transmission. The parallel capability increases efficiency and reduces fossil fuel consumption and we're all in favor of that.
In any case, serial vs. serial/parallel has nothing to do with when the engine is started or running and therefore has nothing to do with this SAE paper's EREV definition.
The Ford Energi models when switched into "EV now" mode are getting close to what I would consider EREV but subjective experience reported by owners at Energi forum sites indicate that acceleration power is weak at highway speeds. I wonder how capable it is at maintaining a US06 cycle on steeper uphill grades.
In other words, how competitive is it with the general performance expected of a vehicle in its class and price at highway speeds and climbing mountain roads? Is it "full performance"? I'm suspicious that it is not fully capable. As I said earlier, I haven't had a chance to drive one yet.
According to an INL (Idaho National Laboratory) report, the Volt can drive 87 mph up a 6% highway grade on battery power alone and that is consistent and competitive with other vehicles in its class.
Last edited:
Similar threads
