Pure BEV Dogma

[Breezy]

The point you seem to be missing is that many of us don't feel the GM created marketing paper you keep quoting is a useful or definitive document. Both the vehicle I outlined and the current Volt are in fact PHEV's. They do in fact have a plug, and they are in fact hybrids.

That's true, by the SAE definition of hybrid. It's not true by the layperson's understanding of what a hybrid is. The Volt is an electric vehicle until the battery runs out. After the battery runs out, it's not afraid to use the engine when it's most efficient to do so. As an owner, i'm just interested in a car that's as efficient and emission-free as possible over time, not one that necessarily fits into our pre-conceived notions of what an EV should or should not be.

It's only been six years since that paper was published. Give the SAE time to adapt.

 

[ItsNotAboutTheMoney]

(I'm in agreement with Doug_G's reminder this should be about the Volt itself, hence this is a post to attempt to clarify facts)



In the Volt this is not the case. From Andrew Farah, Chief Engineer for the Volt:

First, he confirms the ICE can be one of the forces driving the vehicle:

• The Volt has three distinct motive forces in it: a large electric motor, a small electric motor/generator, and a 1.4 liter engine. Up totwo of those three forces can be combined in select ways through the Volt's secret sauce drive unit—given the road demands and state of charge of the battery—to drive the vehicle.
• ...the gas engine can only ever be combined with one of the other motive forces to drive the wheels

Secondly, he confirms that there will be conditions when the ICE does so:

• The gas engine, under most conditions, will be used to drive the generator and produce electricity, and will not be used to drive the wheels.

Finally, the criteria for the car doing so is efficiency, not solely battery depletion:

• The engine is used to partially drive the wheels when the car calculates that it will be a more efficient use of the engine's power.

You can listen to him yourself on that link above.

Additionally, reading the paper you keep posting reveals that what GM published in that SAE paper in 2008 is not what they built in 2011.

For the umpteenth time, it doesn't matter that they built it as a serial-parallel hybrid. Their paper's proposed definition makes no mention of the method of hybridization. Their original concept was a serial hybrid, but they built it as serial-parallel for practical reasons.

The car will not use the engine* until the battery drops to a predefined level. After that point there's a normal hybrid buffer. Whether it's at the top or bottom of the hybrid buffer range when it switches to CS mode is completely irrelevant.

* Yes, I know, except when it's very cold or it's in a maintenance mode.

 

[JRP3]

The point you and others seem to be missing is that the not having to run an engine to provide credible performance is an extremely important distinction.

To some Volt owners it seems.

Do you get it now, Mr JZQ2?

What I get is that you are far too emotional on the subject to continue a rational discussion.

 

[Zzzz...]

Volt is an EV. What kind of EV is not important. What important is that it gives it owners taste of saving $ by driving on electricity. And that push ppl toward not using oil on the long run.

 

[scaesare]

How many people here make reference to the engine driving the wheels, even though it's totally irrelevant to GM's suggested definition

Again, I try to present facts.

Here's the definition from the paper:

“A vehicle that functions as a full-performance battery electric vehicle when
energy is available from an onboard RESS and having
an auxiliary energy supply that is only engaged when the
RESS energy is not available.”

The E-REV is unique from a PHEV in that the vehicle, battery and propulsion system are sized such that the
engine never is required for operation of the vehicle
when energy is available from the battery.

The Volt does not operate in this manner. It engages the ICE under conditions OTHER​ than just battery depletion.

 

[ItsNotAboutTheMoney]

To some Volt owners it seems.

Yes. Lots of them. And I suspect including the many former BMW owners who've bought one.

What I get is that you are far too emotional on the subject to continue a rational discussion.

What I get is that you didn't get the important point that names matter. They matter so much that people are trying to tell GM how they must describe the Volt, using a name that doesn't separate the Volt from other plug-in hybrids that do not have full electric performance. So I ask you, why is the Model S a BEV and a performance sedan instead of just a car?

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Again, I try to present facts.

Here's the definition from the paper:





The Volt does not operate in this manner. It engages the ICE under conditions OTHER​ than just battery depletion.

Besides heat (which I what I think actually precludes it from being an EREV) and maintenance (which is necessary because of having an engine), it does not. There is a preset buffer for CS mode and the engine will only be engaged when the state of charge falls to the maximum limit of that range. If you never get to that SoC limit (excepting blah) you will not run the engine. The use of a buffer does not, in my opinion, breach the definition of E-REV, it's just how the car operates in CS mode for reasons of efficiency. If you want to be strict about the definition of "available" then you'd be requiring an EREV to deplete the battery to 0% SoC, but quite obviously nobody would engineer a car like that. I think it's perfectly reasonable to allow "available" to allow for a CS mode buffer.

 

[Doug_G]

I'd like to welcome all the Volt posters over to the Pure BEV Dogma thread. Feel free to continue to argue meaninglessly over the classification of different plug-in cars. Please note, however, that personal attacks are not permitted in the forum. This discussion is right on the edge of being thrown over to snippiness. Dial it back, please.

 

[Jeff N]

Since we now know that under certain conditions the Volt uses its ICE to directly engage the transmission to move the car forward it not really that either.

GM's EREV definition states no requirements on how the powertrain functions after the gas engine starts up. It only requires that neither torque demand or vehicle speed can cause the gas engine to run and it requires the vehicle to be highway capable as defined by a CARB report.

I see that links to GM's EREV definition have been posted many times here recently so you shouldn't have any problems finding it.

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Besides heat (which I what I think actually precludes it from being an EREV) and maintenance (which is necessary because of having an engine), it does not.

Just to be clear, GM's EREV definition does not include any criteria about cabin heating. You appear to be speaking about your own personal definition of "EREV". GM's definition also does not include any criteria related to maintenance modes although any vehicle with a gasoline or diesel range extender will inherently need them.

Again, GM's definition boils down to 3 criteria:

1. No extender starting due to driver torque demand
2. No extender starting due to vehicle speed.
3. Vehicle must fit Full-Performance EV class criteria in CARB report when it runs on battery

That's it. There are lots of other words in the paper but when taken in their full context that is all that their definition requires.

 

[ItsNotAboutTheMoney]

GM's EREV definition states no requirements on how the powertrain functions after the gas engine starts up. It only requires that neither torque demand or vehicle speed can cause the gas engine to run and it requires the vehicle to be highway capable as defined by a CARB report.

I see that links to GM's EREV definition have been posted many times here recently so you shouldn't have any problems finding it.

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Just to be clear, GM's EREV definition does not include any criteria about cabin heating. You appear to be speaking about your own personal definition of "EREV". GM's definition also does not include any criteria related to maintenance modes although any vehicle with a gasoline or diesel range extender will inherently need them.

Again, GM's definition boils down to 3 criteria:

1. No extender starting due to driver torque demand
2. No extender starting due to vehicle speed.
3. Vehicle must fit Full-Performance EV class criteria in CARB report when it runs on battery

That's it. There are lots of other words in the paper but when taken in their full context that is all that their definition requires.

I disagree. In that paper GM mentions the emissions benefit of E-REV's ability to avoid cold engine runs. Having to start the engine because of low temperature means there will be cold engine runs. 15F is very cold, but it's not what electrical devices would generally consider an extreme low.

 

[Jeff N]

I disagree. In that paper GM mentions the emissions benefit of E-REV's ability to avoid cold engine runs. Having to start the engine because of low temperature means there will be cold engine runs. 15F is very cold, but it's not what electrical devices would generally consider an extreme low.

Reducing emissions is discussed as a benefit of an EREV approach in the paper along with several other benefits but it is not part of the definition of E-REV (as they call it) in the "MAIN SECTION" on page 4 of the document (page 6 of the PDF file). The key paragraph listing the requirements for an EREV vehicle says:

The operation of an E-REV looks similar to that of an Initial EV PHEV; however an E-REV must maintain this mode of operation on all operating schedules when energy is available from the battery. An E-REV does not need to start the engine for speed or power demands from the driver and therefore does not need to transition to a Blended operation strategy when battery energy is available, unlike the Initial EV PHEV.

These are requirements on the propulsion behavior of the vehicle. There is no stated requirement with regards to cabin heating, maintenance modes, or the propulsion behavior after Initial EV has ended.

 

[rolosrevenge]

http://www.media.gm.com/content/dam/Media/microsites/product/volt/docs/paper.pdf

You say potato. I say, read that document and then tell me potato. Especially on page 4 where they proposed a definition of E-REV be:



(RESS=rechargeable energy storage system)
... which makes no mention of serial hybrid operation and instead only emphasizes that it functions as a full-performance BEV in EV mode.

PS When will the 70mph meme die? In CS mode the Volt couples the engine when the car estimates that it'll be more efficient to do so.

According the the paper the SAE defines a hybrid as “A vehicle with two or more energy storage systems both of which must provide propulsion power – either together or independently." and a PHEV as “A hybrid vehicle with the ability to store and use off-board electrical energy in the RESS (rechargeable energy storage system)." According to those definitions, the Volt is a PHEV as set forth by the SAE. Their paper proposes that a new definition is needed because PHEV's don't imply the capability of full EV performance even though it is not precluded by the definition. This claim was not cited. Had I reviewed the paper, (I review for IEEE and Elsevier Journals regularly), I would have required them to cite more sources. Additionally, their definition is rather ambiguous "A vehicle that functions
as a full-performance battery electric vehicle when energy is available from an onboard RESS and having an auxiliary energy supply that is only engaged when the RESS energy is not available."
Define full performance? It really isn't in the paper. We've seen that it can accelerate from 0-100 faster with the engine on than off, does that mean it isn't full performance? Additionally, they had to invent another definition for an "Urban-Capable PHEV" where they arbitrarily limited its performance to differentiate it from an E-REV so they could claim the E-REV was something special. This paper is not very sound and you'll note that it appears the same year that GM goes crawling to congress for money.

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The Volt does not operate in this manner. It engages the ICE under conditions OTHER​ than just battery depletion.

That's because you left the asterisks out of the definition. :wink:

 

[qwk]

According the the paper the SAE defines a hybrid as “A vehicle with two or more energy storage systems both of which must provide propulsion power – either together or independently." and a PHEV as “A hybrid vehicle with the ability to store and use off-board electrical energy in the RESS (rechargeable energy storage system)." According to those definitions, the Volt is a PHEV as set forth by the SAE. Their paper proposes that a new definition is needed because PHEV's don't imply the capability of full EV performance even though it is not precluded by the definition. This claim was not cited. Had I reviewed the paper, (I review for IEEE and Elsevier Journals regularly), I would have required them to cite more sources. Additionally, their definition is rather ambiguous "A vehicle that functions
as a full-performance battery electric vehicle when energy is available from an onboard RESS and having an auxiliary energy supply that is only engaged when the RESS energy is not available."
Define full performance? It really isn't in the paper. We've seen that it can accelerate from 0-100 faster with the engine on than off, does that mean it isn't full performance? Additionally, they had to invent another definition for an "Urban-Capable PHEV" where they arbitrarily limited its performance to differentiate it from an E-REV so they could claim the E-REV was something special. This paper is not very sound and you'll note that it appears the same year that GM goes crawling to congress for money.

I think that the reason that everyone is freaking out over the Volt being called a hybrid, is the fact that the Prius is a pretty crappy hybrid, going by today's technology standards. The Volt is a much better hybrid, so I can understand Volt owners not wanting to be grouped together with all other hybrids. When somebody mentions "hybrid", most people automatically think Prius, just like a tissue being called a Kleenex. If the Prius didn't exist, this thread wouldn't either.

 

[dsm363]

That's why PHEV 40 is a good way to write it. P for plug in which the Volt has. Hybrid for two sources of power. EV for electric vehicle which the Volt is and 40 for 40 miles of EV range. Don't see how Volt owners could get offended by that definition.

 

[Jeff N]

Additionally, their definition is rather ambiguous "A vehicle that functions
as a full-performance battery electric vehicle [emphasis added] when energy is available from an onboard RESS and having an auxiliary energy supply that is only engaged when the RESS energy is not available."
Define full performance? It really isn't in the paper. We've seen that it can accelerate from 0-100 faster with the engine on than off, does that mean it isn't full performance?

The definition comes from a CARB document which is cited as reference [5] immediately following what you quoted from the SAE paper. See page 9 of this executive summary version of that report (same definition section as the longer version). It is available at:

http://www.arb.ca.gov/msprog/zevprog/zevreview/panel_executive_summary.pdf

It defines "full-performance battery electric vehicle" relative to city and neighborhood cars in order to classify vehicles by their propulsion capability:

A. Full Performance Battery Electric Vehicles (FPBEVs)
Full Performance Battery Electric Vehicles are defined in this report as BEVs fully capable of high speed U.S. urban/suburban freeway driving.

B. City Electric Vehicles (CEVs)
City Electric Vehicles are defined in this report as BEVs with limited acceleration and top speed (e.g. 50/60 mph) and thus not suitable for high speed U.S. urban/suburban freeway driving, although at present they must meet all Federal Motor Vehicle Safety Standards (FMVSS) requirements.

C. Neighborhood Electric Vehicles (NEVs)
Neighborhood Electric Vehicles are defined in this report as BEVs capable of top speeds between 20 and 25 mph that meet FMVSS 500 and are limited to roads with posted speeds of 35 mph or less.

The SAE paper does not state any requirements or state any definition relative to a vehicle's propulsion characteristics after the engine has started.

 

[Breezy]

I think that the reason that everyone is freaking out over the Volt being called a hybrid, is the fact that the Prius is a pretty crappy hybrid, going by today's technology standards. The Volt is a much better hybrid, so I can understand Volt owners not wanting to be grouped together with all other hybrids. When somebody mentions "hybrid", most people automatically think Prius, just like a tissue being called a Kleenex. If the Prius didn't exist, this thread wouldn't either.

Yes, I believe that's pretty much it, at least for me. I wouldn't even go so far as to call the Prius crappy, but the Volt operates very differently from it and the "other" PHEVs on the market, because it's normally electric, then gas. That's the way it's designed to run all the time, not in a special mode or under certain specific conditions. There is an important distinction there that is not adequately addressed by the PHEV definition alone.

Certainly, to address the topic of this thread (that we've been moved to), there is no reason the Volt or i3 REx should not be called "electric vehicles."

Personally I'm not bothered by the PHEV moniker as a general classification, with EREV as a specific subcategory.

 

[ItsNotAboutTheMoney]

According the the paper the SAE defines a hybrid as “A vehicle with two or more energy storage systems both of which must provide propulsion power – either together or independently." and a PHEV as “A hybrid vehicle with the ability to store and use off-board electrical energy in the RESS (rechargeable energy storage system)." According to those definitions, the Volt is a PHEV as set forth by the SAE. Their paper proposes that a new definition is needed because PHEV's don't imply the capability of full EV performance even though it is not precluded by the definition. This claim was not cited. Had I reviewed the paper, (I review for IEEE and Elsevier Journals regularly), I would have required them to cite more sources. Additionally, their definition is rather ambiguous "A vehicle that functions
as a full-performance battery electric vehicle when energy is available from an onboard RESS and having an auxiliary energy supply that is only engaged when the RESS energy is not available."
Define full performance? It really isn't in the paper. We've seen that it can accelerate from 0-100 faster with the engine on than off, does that mean it isn't full performance? Additionally, they had to invent another definition for an "Urban-Capable PHEV" where they arbitrarily limited its performance to differentiate it from an E-REV so they could claim the E-REV was something special.

A simple functional definition for full performance would be that performance in EV mode enables it to drive without use of the engine at speeds up to and including all legal or recommended highways speeds in a wide range of conditions, including appropriate use of climate control, with acceleration not materially limited in comparison to similar conventional vehicles, unless the acceleration is similarly limited when the engine is available for use.

(I think that heating in EV mode is important to cut cold running of the engine.)

But really, to me the "full performance" meaning is intuitively obvious. Would people think that the acceleration in EV-only mode sucks compared to other cars? Does it suck similarly when it can use the engine as well? And I'd add, is it going to have to run the engine for heat?

Really, I don't think an exacting scientific definition is an issue here. The document makes the concept clear.

This paper is not very sound ...

Well, that's really neither here nor there. What matters is whether the E-REV approach leads to a materially different product compared to the usual PHEV approach so it's valid for GM to use a different name, and whether the name they chose is accurate.

...and you'll note that it appears the same year that GM goes crawling to congress for money.

I don't see the relevance of that point. Do you think that politics and economics should decide the validity of terminology for a type of car? Is your opinion of the naming based on your views on government intervention in the market?

 

[Doug_G]

Well, that's really neither here nor there. What matters is whether the E-REV approach leads to a materially different product compared to the usual PHEV approach so it's valid for GM to use a different name, and whether the name they chose is accurate.

Yes, the Volt is materially better than the Plug-in Prius. Much better. That doesn't necessarily mean it deserves a unique moniker. GM decided to create a new moniker for marketing reasons. But they also advertised it as "the electric car that goes farther", which simply seeded confusion in the market. So I don't take their word as gospel.

Car companies are known for spouting acronyms to differentiate the product, while leaving consumers with no clue what they mean. How many people know what VTEC is? Variable Valve Timing and Lift Electronic Control. Still don't know, right? Basically it allows Honda to reduce fuel consumption under gentle driving, and boost performance at the expense of economy when driving hard. I bet 99% of consumers have no clue what VTEC is. So what is any consumer going to make of PHEV versus EREV? Not much.

I would argue that this sort of terminology is fairly pointless. What's better is if the dealer can explain the advantages of their car to the consumer. Unfortunately GM dealers are doing a terrible job of selling the Volt. Indeed most are trying hard not to sell it.

 

[ZsoZso]

I think that the reason that everyone is freaking out over the Volt being called a hybrid, is the fact that the Prius is a pretty crappy hybrid, going by today's technology standards. The Volt is a much better hybrid, so I can understand Volt owners not wanting to be grouped together with all other hybrids. When somebody mentions "hybrid", most people automatically think Prius, just like a tissue being called a Kleenex. If the Prius didn't exist, this thread wouldn't either.

IMHO, the problem stems from Toyota starting out with a missleading marketing term calling the basic Prius a hybrid. That car is 100% gasoline powered vehicle. The battery + electric motor serves as a temporary storage and reuse system for reducing the energy loss during breaking via the regenerative breaking system. In other words it is a fuel-saving mechanism for gasoline vehicles.

On the other hand, the Volt deserves the name hybrid, because it can be powered by either electricity or gasoline (or combination of the two). The plugin-prius may argue for the title hybrid, although due to the extremely limited pure-EV range, its more of a gimmick than a real functionality.

What I am trying to say is, that I understand the frustration of the Volt owners who want to differentiate their vehicle from the likes of the Prius, the Volt is indeed a different category.
Unfortunately, the marketing-hype induced incorrect naming is already stuck with the Prius, therefore it is a difficult to fix situation. But calling the Volt simply an EV is just as incorrect as calling the Prius a hybrid.

 

[qwk]

IMHO, the problem stems from Toyota starting out with a missleading marketing term calling the basic Prius a hybrid. That car is 100% gasoline powered vehicle. The battery + electric motor serves as a temporary storage and reuse system for reducing the energy loss during breaking via the regenerative breaking system. In other words it is a fuel-saving mechanism for gasoline vehicles.

On the other hand, the Volt deserves the name hybrid, because it can be powered by either electricity or gasoline (or combination of the two). The plugin-prius may argue for the title hybrid, although due to the extremely limited pure-EV range, its more of a gimmick than a real functionality.

What I am trying to say is, that I understand the frustration of the Volt owners who want to differentiate their vehicle from the likes of the Prius, the Volt is indeed a different category.
Unfortunately, the marketing-hype induced incorrect naming is already stuck with the Prius, therefore it is a difficult to fix situation. But calling the Volt simply an EV is just as incorrect as calling the Prius a hybrid.

Yes, it is too late to fix the situation. It is, what it is. Today's marketing agencies go as close to false advertising as they can, with many simply marketing pure lies. Nobody is held accountable anymore.

 

[brianman]

That's kinda what I'm saying... but to the layperson, if it has a plug, it's electric and if it has an ICE and a plug, it's a range-extended electric. "Hybrid" seems to the layperson to be reserved to those that don't have a plug but do have an electric assist. I realize that technically this is not accurate...

Do you really want a race to the bottom by choosing terminology based on what you think today's layperson comprehends?

My preference is to educate and elevate the uniformed with accurate terminology, rather than make everything nonsensical by corrupting terminology based on the financial motivations of marketing folk.