Pure BEV Dogma

[brianman]

True story, I told my wife that we should look into leasing a Volt. She asked what type of car it was. I said a Plugin Hybrid that can go for 40 miles on only electricity. She said, "I like hybrids". If I had said it's an extended range electric vehicle she would have had no idea what that means.

Sigh. You have much to learn.

"Well, it's like a Tesla but only contains 10% awesome."
"Hm. Don't we want 100% awesome?"
"Yes, we do. "

 

[rolosrevenge]

Sigh. You have much to learn.

"Well, it's like a Tesla but only contains 10% awesome."
"Hm. Don't we want 100% awesome?"
"Yes, we do. "

So true, but I just bought a house so my money's all gone. $199/mo lease < less than I pay in monthly gas for my current car. $900/mo "lease" > leaves me with -$500/mo in budget and saving nothing for the future. 10% awesome is sadly all I can afford unless I trip over a brief case of hundreds. It's arguably infinitely better than 0% awesome.

 

[stopcrazypp]

So "It's not comparing EV vs CS mode" but actually it really is? That seems like an incoherent argument.

No, I'm saying that it's not directly comparing EV vs CS (which is why you don't find that in the paper as you note), but it is comparing EV vs the max performance of the car. So indirectly EV mode must perform as well if not better than CS. The two statements are not contradictory.

I'm not sure about the Fisker, but the ICE does not kick in on the ELR unless the battery is empty and the vehicle has already switched over to hybrid mode (same as Volt). What some people are complaining about is that the ELR goes 0-60 mph faster in hybrid mode than it does in EV mode. The Volt is about the same in both modes going 0-60 mph but diverges at 0-70 and from 45-65.

The Volt diverges a bit above 70 in testing, but still close enough (0-60, top speed, 1/4 mile, the three specs most people care about, is pretty much the same) that GM doesn't have to quote different numbers for the two modes. The ELR diverges significantly in 0-60 mph and given GM says they accomplished this purely with software vs the Volt, it's pretty clear they have been artificially limiting the Volt's CS performance to match the EREV criteria.

That data demonstrated that the Volt is also faster in hybrid mode much like the ELR. Do you really think the GM engineers who wrote this paper (and were working on the Volt program) meant to define EREV in a way that excluded the Volt?

See my point above. And given the Volt was still under development at the time, it's entirely possible that the Volt had changed to outside the boundaries of the definition by the time it was fully developed.

They were a little loose in what was normative and what was merely descriptive...By the way, why would it make "any sense in engineering" to artificially limit the performance of the hybrid mode in the Volt or ELR so that it performs no faster than the battery limitations of the EV mode? Why would anyone do that other than other than to satisfy irrational EV purity demands?

What I mean is that it doesn't make any sense in engineering terminology to define a car the way you have defined (dependent on "competitive" features vs other cars). Yes, when you engineer a car you want to make it more flexible. But what I mean is you can't be loose that way when coming up with an engineering term (as the paper was intended to do). It must be clear/consistent so you don't have ambiguity.

I've already said that I think the Ford Energi's optional "EV now" mode would quality as an EREV operating strategy if Ford made it the default when you start the car. They chose not to because they knew its performance was not fully competitive.

What I'm asking is if the Energi would fit GM's definition under your interpretation of "full-performance", not about the default vs non-default issue (which is about your definition of EREV, which is clearly different than GM's). My point is that the cut-off point for EREV eligibility is very unclear using such a definition of "full-performance".

The key difference between ordinary PHEV and EREV is whether the engine will start up when the driver stomps the accelerator or drives up steep hills at full speed.

The thing is it doesn't start up in EV mode in "ordinary PHEVs" and it does start up in mountain/hold/sport modes in "EREVs", so how important is that distinction to users if they can just push a button to change things?

You still haven't offered any evidence in support of that claim.

I didn't because I assumed it (that GM defined EREV=series PHEV) would be self-evident to any Volt follower (esp. if you frequented gm-volt.com like I did during the early days).
Here's a bunch of articles that discuss this in detail:
http://blogs.cars.com/kickingtires/2010/10/the-great-chevy-volt-hybrid-mishap-explained.html
http://www.electric-vehiclenews.com/2010/10/chevrolet-volt-is-not-series-hybrid.html
http://www.edmunds.com/car-reviews/features/how-the-2011-chevrolet-volt-works.html

I'm arguing that GM's notion of EREV conveys a useful and important characteristic. It says that if you stomp on the accelerator or climb a steep road at the highest speed the car can go in its default operating mode that it will not start the engine unless the battery is "empty".

That sounds very convoluted. I say it's more far important to users what the actual EV mode characteristics are (0-60 and top speed) rather than whether it's a default setting or after pushing a button

 

[Reykjavik]

Adding more labels doesn't clarify things. If people are confused about what a hybrid is, it is easier to explain it than it is to introduce a new label and then explain both. EREV is marketing, it sounds good. It sounds like a better version of an electric vehicle, which is great for GM's bottom line, but it is misleading. Calling it a plug in hybrid is accurate, it works with the vocabulary that has been in use since Toyota introduced the Prius. And if you want to tag a "40" subscript for its all electric range on there, you can. But the Volt doesn't need to a separate label to distinguish it from the plug in Prius. Both are plug in hybrids, one has short electric range, the other has decent electric range.

 

[JRP3]

EREV is marketing, it sounds good. It sounds like a better version of an electric vehicle, which is great for GM's bottom line, but it is misleading.

Actually I think it ended up hurting GM's bottom line and was a marketing failure for reasons I and others have previously discussed.

 

[Jeff N]

No, I'm saying that it's not directly comparing EV vs CS (which is why you don't find that in the paper as you note), but it is comparing EV vs the max performance of the car. So indirectly EV mode must perform as well if not better than CS. The two statements are not contradictory.

I find this line of argument unconvincing.

If the authors of the paper wanted to define "full-performance" in terms of the vehicles extended range performance (even via a level of indirection) they would have said that themselves.

The Volt diverges a bit above 70 in testing, but still close enough (0-60, top speed, 1/4 mile, the three specs most people care about, is pretty much the same) that GM doesn't have to quote different numbers for the two modes. The ELR diverges significantly in 0-60 mph and given GM says they accomplished this purely with software vs the Volt, it's pretty clear they have been artificially limiting the Volt's CS performance to match the EREV criteria.

Why would GM do that? Just so they can use the EREV term in their marketing material? I would think the marketing folks would much rather have marketed higher performance numbers if the engineers thought they could provide them at speeds down to 0-60.

You do know that the ELR is also marketed as an EREV?

Cadillac Begins Shipping ELRs to Dealerships

A more likely explanation is that GM was being more conservative in the engineering of the first Volt model. Originally they were going to use only 50% of the pack SOC range. The production car used 65%.

With more real world experience and testing they are now willing to push the hardware a bit harder. The ELR uses about 72% of the battery (about the same as the Ford Energi). The ELR also draws about 5-20% more power from the battery. And it drives the motors harder with additional power from the engine generator in CS mode.

With a little research this morning, I found a recent statement by a well-informed and credible GM service support engineer (WopOnTour at GM-Volt.com). He said the ELR has some improved electrical cabling and components that enable the higher performance -- it's not purely software.

See my point above. And given the Volt was still under development at the time, it's entirely possible that the Volt had changed to outside the boundaries of the definition by the time it was fully developed.

So now the Volt isn't an EREV either? I find this pretty convoluted and implausible. It's much more plausible that "full-performance" was meant to convey a generalized expectation that cars designed and marketed as EREV would be generally competitive in their performance in battery-only mode.

What I mean is that it doesn't make any sense in engineering terminology to define a car the way you have defined (dependent on "competitive" features vs other cars). Yes, when you engineer a car you want to make it more flexible. But what I mean is you can't be loose that way when coming up with an engineering term (as the paper was intended to do). It must be clear/consistent so you don't have ambiguity.

I think the paper could have been written with better clarity about what statements were normative specifications and where statements were explanatory or non-normative descriptions.

In some engineering cultures this is done explicitly using formatting conventions. I don't know what conventions are common in SAE papers.

What I'm asking is if the Energi would fit GM's definition under your interpretation of "full-performance", not about the default vs non-default issue (which is about your definition of EREV, which is clearly different than GM's). My point is that the cut-off point for EREV eligibility is very unclear using such a definition of "full-performance".

I think GM's definition and mine are the same because, after further parsing and reflection, I don't think "full-performance" is a normative (required) part of their definition of EREV in the SAE paper.

I'll assume you are asking my personal opinion of whether the Ford Energi "EV now" mode is "full-performance" from a non-normative perspective using GM's description of the meaning of that phrase.

I haven't driven one but I did look up it's track numbers from Car and Driver Magazine and some comparable from zeroto60times.com.

2013 Ford C-MAX Energi (EV now) 0-60 mph 16.1 Quarter mile 20.1 (@65 mph)

1980 Ford Pinto (4spd) 0-60 mph 15.7 Quarter mile 20.5

1974 Toyota Corolla 1200 0-60 mph 16.0 Quarter mile 19.7

2001 Toyota Prius Hybrid 0-60 mph 12.9 Quarter Mile 19.0

I think that makes it drivable although it's only competitive with the slowest cars listed in the zeroto60times.com data and essentially all of those cars are 1960-1980 era econoboxes or Diesels. Today's econoboxes are quite a bit faster.

I would say it should fit within the very outer realm of "full-performance".

The thing is it doesn't start up in EV mode in "ordinary PHEVs" and it does start up in mountain/hold/sport modes in "EREVs", so how important is that distinction to users if they can just push a button to change things?

Huh, I don't understand what you are getting at. The Volt/ELR do not start up in mountain, hold, or sports mode. The car reverts to "normal" mode every time you turn it on.

I didn't because I assumed it (that GM defined EREV=series PHEV) would be self-evident to any Volt follower (esp. if you frequented gm-volt.com like I did during the early days).
Here's a bunch of articles that discuss this in detail:
http://blogs.cars.com/kickingtires/2010/10/the-great-chevy-volt-hybrid-mishap-explained.html
http://www.electric-vehiclenews.com/2010/10/chevrolet-volt-is-not-series-hybrid.html
http://www.edmunds.com/car-reviews/features/how-the-2011-chevrolet-volt-works.html

But series hybrid mode says nothing about whether the engine will start up if you try to accelerate too fast. It's just describing the power flow path from the engine to the wheels. It has nothing whatever to do with EREV behavior.

In fact, ironically, the ELR is almost certainly operating in series hybrid mode when it gets the 0-60 mph numbers that you think makes it a non-EREV car. The Volt has been measured with OBD-II tools doing 0-100 mph track timing and it stays in series hybrid mode the entire time. The Volt blends about 75 kW from the battery and gets another 40 kW from the generator driven by the gas engine. The ELR presumably gets 90-100 kW from the battery and 40-50 kW from the generator. It's total system power is rated around 154 kW in the latest specs I saw from Cadillac.

That sounds very convoluted. I say it's more far important to users what the actual EV mode characteristics are (0-60 and top speed) rather than whether it's a default setting rather than after pushing a button.

The goal of a driver who cares about the EREV distinction is to be able to drive the car without starting the fossil fuel engine until it's needed because the battery runs out without having to push buttons or expectantly concentrate on power displays that indicate that accelerating any faster would start the engine. Such a driver just wants to drive and not be surprised by engine startup.

- - - Updated - - -

So you are hinging the entire argument on a specific condition that is extremely rare and only lasts an extremely short time period the few times it may actually happen. And you think this distinction carries great weight and requires a completely new vehicle classification.

Certainly not.

I'm arguing that GM's notion of EREV conveys a useful and important characteristic.

The threat of starting the engine on a Prius Plugin is very real. You can conservatively drive it on flat roads up to 62 mph without starting the engine but you have to pay close attention when merging onto the freeway where the engine comes close to starting during typical driving.

The threat is presumably less on a Ford Energi (I haven't driven one yet). However, I'm guessing that it would be relatively easy to press the accelerator hard enough to start the engine when passing on the freeway or when driving up steep hills (think San Francisco or Seattle) or mountain highways. Those are common everyday driving conditions for many prospective customers.

 

[rolosrevenge]

So now the Volt isn't an EREV either

Technically nothing is an EREV and that's the point. Its definition is so convoluted to match what the Volt is, it is a meaningless term. It only appeared when they were in dire need of a bailout and people wanted EVs. Remember Chrysler's EV program that magically appeared back then which was quietly cancelled after they got the money? Pretty much the same thing here, other than GM took their innovative plugin hybrid and tried to rebadge it as an EV to stupid politicians to get money.

 

[brianman]

Technically nothing is an EREV and that's the point. Its definition is so convoluted to match what the Volt is, it is a meaningless term. It only appeared when they were in dire need of a bailout and people wanted EVs. Remember Chrysler's EV program that magically appeared back then which was quietly cancelled after they got the money? Pretty much the same thing here, other than GM took their innovative plugin hybrid and tried to rebadge it as an EV to stupid politicians to get money.

+1

I must admit that part of what sours me on the "EV-ish terminology" is that such terminology interacts with public policy, funding, etc. If it was just private companies making stupid choices for terminology and the crappy ones dying out (dying, as in not getting bailed out) then I probably wouldn't care.

 

[Jeff N]

Technically nothing is an EREV and that's the point. Its definition is so convoluted to match what the Volt is, it is a meaningless term. It only appeared when they were in dire need of a bailout and people wanted EVs. Remember Chrysler's EV program that magically appeared back then which was quietly cancelled after they got the money? Pretty much the same thing here, other than GM took their innovative plugin hybrid and tried to rebadge it as an EV to stupid politicians to get money.

LOL. Try again... The Volt concept car was shown at the Detroit Auto Show in January 2007. The E-REV or EREV acronym was in use by at least June 2007. Around the same time, GM contracted with LG and A123 to produce prototype battery packs for testing. By November 2007 the Volt was approved as a production car with a public target production date of November 2010 (when my own Volt was manufactured).

The Great Recession which drove GM into bankruptcy didn't officially start until December 2007. US automobile sales didn't begin dropping until the early part of 2008. The bailout didn't happen until late 2008 and 2009.

 

[Jeff N]

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).

This is exactly my thoughts as well. I interpret "full performance in EV mode" to be equal to or greater than hybrid mode performance. I think this interpretation is what the GM authors of the SAE paper you linked intended, and it makes the EREV distinction more useful.

Okay, so it turns out that right there in plain sight in the GM SAE paper it explains that the phrase "full-performance" is taken from a CARB report (listed as reference 5 in the SAE paper).

That CARB document uses "full-performance" to distinguish BEVs that are capable of being driven on the freeway from city and neighborhood cars that are less capable.

See page 9-10 of http://www.arb.ca.gov/msprog/zevprog/zevreview/panel_executive_summary.pdf.

Here's how the CARB report contrasts these definitions:

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

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.

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.

So, when the GM paper says

The authors propose the following definition: “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.” This is very similar to a vehicle envisioned in the 2007 ARB Expert panel report [5], when they described,

“ ....This type of vehicle can operate as a full performance ZEV, during the time the ICE is not operating, and can avoid the cold start emission problem discussed above and it requires a relatively large energy battery and a large full performance, electric drive propulsions system, similar to FPBEV or FCEV....”

And then

As a full-performance battery electric vehicle, the battery, motor, and power electronics must be sized for the full capability of the vehicle.

There can be no doubt that "full-performance" in this context means only that it is capable of operating as a general purpose freeway-capable car based on the CARB report definition and there is no implication of any kind that the battery mode performance must match that of the range extended performance.

Does anyone disagree?

 

[Yggdrasill]

I think you nailed it, Jeff.

 

[stopcrazypp]

If the authors of the paper wanted to define "full-performance" in terms of the vehicles extended range performance (even via a level of indirection) they would have said that themselves.

There may be many other modes other than EV and CS modes, which is why they don't define it directly as an EV vs CS mode as that would be overly specific. I'm describing it using EV vs CS mode because it's a simple litmus test.

Why would GM do that? Just so they can use the EREV term in their marketing material? I would think the marketing folks would much rather have marketed higher performance numbers if the engineers thought they could provide them at speeds down to 0-60.

Being able to label the Volt as an "EV" is far more important than better 0-60 numbers in CS mode. Keep in mind GM had a huge backlash after the WKTEC movie and having the Volt be called an "EV" was critical to their response.

You do know that the ELR is also marketed as an EREV?

Yes, and I'm saying that it's ironic that it's not.

He said the ELR has some improved electrical cabling and components that enable the higher performance -- it's not purely software.

Perhaps, but a bulk of it was software. Software that can equally be applied to the Volt. I know some Volt modders have gotten a better 0-60 from the car by taking advantage of the ICE after removing some limiters. It would have to be a pretty big coincidence to have the same 0-60, quarter mile, top speed in both modes for the Volt without even a bit of effort in the tuning to keep them similar.

So now the Volt isn't an EREV either? I find this pretty convoluted and implausible. It's much more plausible that "full-performance" was meant to convey a generalized expectation that cars designed and marketed as EREV would be generally competitive in their performance in battery-only mode.

The Volt is an EREV under the "full-performance" criteria, you just have to be loose with the second criteria about turning on the ICE. I say the Volt is the second-closest to the EREV definition (i3 Rex is number one). No other cars I know of satisfies the "full-performance" criteria.

I think the paper could have been written with better clarity about what statements were normative specifications and where statements were explanatory or non-normative descriptions.

Why would you put explanatory/non-normative descriptions in the single sentence definition of the EREV term?
If you look at the SAE definitions of hybrid and PHEV in the same paper, you see it's pruned down to only the most essential words.

I think GM's definition and mine are the same because, after further parsing and reflection, I don't think "full-performance" is a normative (required) part of their definition of EREV in the SAE paper.

If you leave out "full-performance" all you are left with for the first half is that the car operates like a BEV and even a Prius can satisfy that requirement.

I haven't driven one but I did look up it's track numbers from Car and Driver Magazine and some comparable from zeroto60times.com. I would say it should fit within the very outer realm of "full-performance".

That's the problem, you have to look at a table of other cars to compare and I don't think any engineering term would be defined that way.

Huh, I don't understand what you are getting at. The Volt/ELR do not start up in mountain, hold, or sports mode. The car reverts to "normal" mode every time you turn it on.

Sorry, I should have been more clear. I mean you can "start up" the ICE in the Volt/ELR by pressing the mountain/hold mode button, not talking about which mode it defaults to when starting up the car. And doing some research, the Energi actually remembers the setting you set previously (so you can stay in EV mode without pressing buttons).

But series hybrid mode says nothing about whether the engine will start up if you try to accelerate too fast. It's just describing the power flow path from the engine to the wheels. It has nothing whatever to do with EREV behavior.

GM made a big deal for 3 years about how the engine in the Volt never powers the wheels (see the articles I linked). That's what impressed the public the most and clearly differentiated the car from the Prius. There are people are still under the impression that this is still the case. That was my point there. The "EREV" as it is now is far more complex to explain to people than series PHEV.

In fact, ironically, the ELR is almost certainly operating in series hybrid mode when it gets the 0-60 mph numbers that you think makes it a non-EREV car.

Doesn't matter what mode it's operating in, as long as it's faster than the EV mode then it's non-EREV as at least one component in the three components pointed out by GM is undersized. If GM could, I bet they would have made the EV mode in the ELR perform the same if not better than the CS mode.

The goal of a driver who cares about the EREV distinction is to be able to drive the car without starting the fossil fuel engine until it's needed because the battery runs out without having to push buttons or expectantly concentrate on power displays that indicate that accelerating any faster would start the engine. Such a driver just wants to drive and not be surprised by engine startup.

I'm saying the buttons/modes don't matter (as long as there is an "EV only" mode). Only the actual capabilities.

- - - Updated - - -

Okay, so it turns out that right there in plain sight in the GM SAE paper it explains that the phrase "full-performance" is taken from a CARB report (listed as reference 5 in the SAE paper).

That CARB document uses "full-performance" to distinguish BEVs that are capable of being driven on the freeway from city and neighborhood cars that are less capable.

See page 9-10 of http://www.arb.ca.gov/msprog/zevprog/zevreview/panel_executive_summary.pdf.

Actually it references specifically to this paragraph on page 165 which (surprise, surprise) describes a series PHEV! (edit: didn't see it was the same report, just different link)
http://www.lifepo4.info/Battery_study/Batteries/zev_panel_report.pdf

A different PHEV approach is to utilize series hybrid architecture. Instead of a large ICE and relatively small energy battery in a parallel configuration, it uses a small ICE and relatively large energy battery in a series configuration...This type of PHEV can operate as a full performance ZEV, during the times that the ICE is not operating, and can avoid the cold start emissions problem discussed above, but it requires a relatively large energy battery and a large, full performance, electric drive propulsion system, similar to a FPBEV or FCEV...

 

[JRP3]

If "full performance" is simply used to describe a highway capable vehicle in EV mode then that can also apply to other PHEV's that can drive on the highway without starting the ICE, even if they may start the ICE to achieve a specific 0-60 time or under hard acceleration, or to exceed the speed limit. There are no acceleration numbers specific to the definition of "highway capable vehicles" that I'm aware of. I'd assume any vehicle capable of reaching the legal posted speed limit is "highway capable". More likely it's anything that's not a NEV or similar.

 

[Jeff N]

If "full performance" is simply used to describe a highway capable vehicle in EV mode then that can also apply to other PHEV's that can drive on the highway without starting the ICE, even if they may start the ICE to achieve a specific 0-60 time or under hard acceleration, or to exceed the speed limit. There are no acceleration numbers specific to the definition of "highway capable vehicles" that I'm aware of. I'd assume any vehicle capable of reaching the legal posted speed limit is "highway capable". More likely it's anything that's not a NEV or similar.

The EREV definition requires both full-performance battery electric vehicle operation and says this must continue until the battery charge runs out. This prevents the driver from unintentionally starting the engine during fast acceleration or when achieving higher speeds while there is still charge left in the battery. That is what distinguishes EREV from a full-performance capable PHEV.

Here is another quote from the same CARB report that clarifies the intended meaning of "full-performance":

For this report, BEVs have been divided into two main categories – (1) full performance battery electric vehicles (FPBEVs) of all sizes and driving ranges, and (2) all other, less than full performance, battery electric vehicles, including neighborhood electric vehicles (NEVs), utility electric vehicles (UEVs), and city electric vehicles (CEVs). This distinction is relevant when considering the practicality and likelihood of high volume BEV substitution for conventional vehicles and the associated societal benefits. FPBEVs are not performance limited (i.e., acceleration and top speed) compared to conventional internal combustion engine (ICE) powered vehicles and are fully capable of U.S. urban freeway driving. This is an important consideration given that driving conditions and practices in most U.S. urban areas include a significant amount of freeway driving.

Note that the GM SAE paper defines an EREV as:

“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.”

Later it adds:

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.

There's nothing complicated or confusing here. This is a simple and useful vehicle characteristic that prevents drivers from unintentionally starting the fossil fuel engine.

 

[JRP3]

That's one opinion. The other is that it's a minor difference that in no way required the creation of a new term, especially when, counter to your claim, that term has led to widespread and well documented confusion and misinformation. That fact is there is plenty that is complicated and confusing. This 58 page 575 posts and counting thread would not exist were it not for the GM marketing version of The Emperor's New Clothes, and you'd be blissfully and happily driving your plug in hybrid Volt without the need to try and make it into something else.

 

[ChadS]

I agree the Volt *is* a plug-in hybrid; I think everybody agrees on that part. I agree some people are confused by EREV; though they are confused by BEV and PHEV as well. Some are even confused by hybrid, still.

I disagree that the difference (between a PHEV like the Volt and a PHEV like the PiP) is minor. Driving a Volt is extremely different than driving a plug-in Prius. I have a plug-in Prius; I hate driving it because I hate every time that engine comes on - which is often, and not really under my control. But if my wife couldn't have her Model S for some reason, she would have a Volt and we would both be extremely happy driving it. I know about maintenance mode and such, but I have taken a Volt on a long trip and the only time the engine came on was when the battery was depleted. That is exactly what I want out of a PHEV, but most PHEVs don't behave that way (I've test driven the Fords, too; they are kind of in the middle - the engine comes on less often than the Prius, but it still does when you goose the pedal). Even though they are in the same category on a spectrum, the cars have a huge qualitative difference to me.

I agree it's hard to create clean categories on a spectrum, and I may even be able to agree there shouldn't be a new category for that reason. GM very well could have come up with a better way to advertise the difference. But I disagree very strongly that it's a minor difference, or that it's not worth communicating. I also know that almost every time I say "plug-in hybrid" to a newbie, the next thing they say is "oh, like a Prius...?" which, for the Volt, is NOT the message I am trying to get across. Calling the Volt a PHEV may work well for the audience on this forum, which by and large (though there are strong exceptions even here) sees hybrids favorably. But many Americans really hate the Prius, and are not at all interested in a similar car. I don't blame GM at all for trying to distance their car from the Prius, even though I do disagree with some of the ways they do so.

 

[Doug_G]

I disagree that the difference (between a PHEV like the Volt and a PHEV like the PiP) is minor. Driving a Volt is extremely different than driving a plug-in Prius.

Just like driving a Volkswagen Beetle is a little different from a Corvette. Both are considered ICE.

 

[ChadS]

Yes, they are both ICE; but I am not arguing that the PiP and Volt aren't both PHEVs - so that doesn't change my point.

If somebody asked you what a Corvette is, you wouldn't say "it's an ICE, just like the Beetle you are familiar with". (If you did, you would lead some people to ignore the Corvette when they might love it if they tried it). To do a good job of answering their question, you would describe the Corvette in terms of how it's different than the Beetle. In fact, you would probably use the term "sports car", even though there is no clean definition of that term, and ICEs are on a spectrum from economy cars to sports cars. The difference between a Beetle and a Corvette is very significant, and anybody trying to sell the Corvette is - rightly in principle, though of course they could go wrong in tactics - going to work very hard to convey that.

I'm not saying we need a new term for this. I agree PiP and Volt are in the same category, and that defining a new term can be confusing. I'm just pointing out that (unlike the Beetle and Corvette) they are unfamiliar to many, and describing very different, unfamiliar cars with the same PHEV term (especially when the term is so closely related to the HEV term which describes yet another type of car that many people don't like) can ALSO be confusing. Even if it is correct by definition.

 

[brianman]

I agree the Volt *is* a plug-in hybrid; I think everybody agrees on that part.

Actually, I think that is part of the problem/discussion in this thread. Some have argued against calling a Volt a hybrid. Though plug-in has been non-objectionable to all, IIRC.

 

[Jeff N]

Actually, I think that is part of the problem/discussion in this thread. Some have argued against calling a Volt a hybrid. Though plug-in has been non-objectionable to all, IIRC.

I agree that it operates as a hybrid part of the time so it is therefore a hybrid and it plugs in therefore it is a plugin hybrid part of the time and therefore it is a plugin hybrid.

Stopping with that description alone misses an important qualitative difference which is that it operates as a "full performance battery electric vehicle" for the first 40-something miles after a full charge and as we all know, FPBEVs are nice to drive. That is why I think an EREV descriptor is useful.