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Pure BEV Dogma
- Thread starter bonnie
- Start date
But not as clear as:
Does it have an internal combustion engine: Yes -- Does it have an electric motor for propulsion: No -- Does it plug in: No= ICE
Does it have an internal combustion engine: Yes -- Does it have an electric motor for propulsion: Yes -- Does it plug in: No = HYBRID
Does it have an internal combustion engine: Yes -- Does it have an electric motor for propulsion: Yes -- Does it plug in: Yes = PLUGIN HYBRID
Does it have an internal combustion engine: No -- Does it have an electric motor for propulsion: Yes -- Does it plug in: Yes = BEV
Does it have an internal combustion engine: Yes -- Does it have an electric motor for propulsion: No -- Does it plug in: No= ICE
Does it have an internal combustion engine: Yes -- Does it have an electric motor for propulsion: Yes -- Does it plug in: No = HYBRID
Does it have an internal combustion engine: Yes -- Does it have an electric motor for propulsion: Yes -- Does it plug in: Yes = PLUGIN HYBRID
Does it have an internal combustion engine: No -- Does it have an electric motor for propulsion: Yes -- Does it plug in: Yes = BEV
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.
While Jeff N points out that the Volt's EV and hybrid modes are not exactly equal, they are never more than 1-4 horsepower different throughout the entire 0-100 mph speed range, and both are limited to 100 mph. This is as close as we can expect the calibration engineers to get.
Exceptions to "never using the ICE until the battery is depleted" are necessary. The Volt has ICE maintenance mode, hold mode, and the "engine running due to temperature" mode. The first two are wonderful, the last one I despise. I certainly hope the i3 has ICE maintenance mode as Jeff N points out. Otherwise, it will have rusted into one piece before I would ever use it. A range extender that you cannot count on is worse than not having one at all.
GSP
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I have to agree on this point! :wink: GSP
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You are correct on all points, no argument at all, except for the contradiction thing...
I think we both see the entire picture. Surely you realize that I know the Volt is a PHEV with a ICE. I am not ignoring it. However if I am, the maybe you are suffering from "EV blindness" by occasionally ignoring that the Volt's EV capabilities are what differentiate it from most other cars.
The EV capabilities are why people buy Volts instead of pure ICE cars and non-plugin HEVs. This is where most people are coming from, myself included.
I understand that if you are shopping for EVs, the thing that is different about the Volt is that it also has an ICE. This is a different viewpoint that is just as valid, but it is not the only valid viewpoint.
GSP
Please show me where the GM SAE paper states or even implies this interpretation. I didn't see that anywhere but maybe I missed it.
By my reading, the GM engineers did not intend the EREV "full performance" in battery mode to be defined in any way at all relative to extended range performance.
Do you have a source for this claim?
I see no effort by GM engineers to force hybrid (CS) mode to be artificially limited into having the same exact performance as battery depletion mode. What would be the motivation for doing that other than someone's idea of ideological purity? The Volt's motors are capable of higher performance than the 16 (or 16.5) kWh pack can provide so the car gets a bit more power when the battery is supplemented by the engine and generator.
Here's is data from MotorTrend comparing the 2011 Volt in battery mode versus hybrid mode (CD vs. CS):
Code:
2011 Volt CD v. CS Mode
ACCELERATION TO MPH
0-30 3.0 3.2
0-40 4.5 4.6
0-50 6.4 6.4
0-60 8.8 8.7
0-70 11.9 11.3
0-80 16.0 14.5
0-90 21.3 18.3
0-100 29.8 23.0
PASSING, 45-65 MPH
4.9; 4.5Source:
2011 Chevrolet Volt First Test - Motor Trend
JRP3
Hyperactive Member
No I am fully aware that what differentiates the Volt is it's use of both technologies. That makes it different than an ICE and different than an EV. It makes it a plug in hybrid. We both agree on that, the only difference is you and others think it needs another distinguishing term beyond that, though no one seems to agree about what exactly that term should cover. That's the problem with making up a term for marketing purposes. GM created a term that only fit it's vehicle. Think of it this way, Toyota could take the original Prius hybrid, not change the design one bit, but increase the pack size and electric motor sizes, such that it has full performance in EV only mode, even if it only went 10 miles or so on electricity, and it meets the criteria for EREV. They could also build the same vehicle but give it 60 miles of electric range but maybe the ICE would come on above 80 when you floor it or something. That vehicle, certainly capable of more real world electric only use, would fail the EREV criteria. Or not, depending on who is interpreting it at the moment.
Sure, but you're also buying it because of the ICE capabilities, and the fact that one plug in hybrid might run its ICE a bit more under different conditions than another plug in hybrid doesn't warrant a special term, especially when an arguably better vehicle with more EV only range could be built that failed to meet the specific criteria. Since Tesla built an EV with more range and better performance than any other EV they could have come up with a special name for that as well but didn't see the need.
You forgot one....
Does it have an internal combustion engine: Yes -- Does it have an electric motor for propulsion that provides full performance comparable to other vehicles in its class without starting the ICE: Yes -- Does it plug in: Yes = EXTENDED RANGE ELECTRIC VEHICLE
You forgot one....
Does it have an internal combustion engine: Yes -- Does it have an electric motor for propulsion that provides full performance comparable to other vehicles in its class without starting the ICE: Yes -- Does it plug in: Yes = EXTENDED RANGE ELECTRIC VEHICLE
That is just a marketing ploy to confuse people. It's a plug in hybrid, and still has a dirty gas engine.
JRP3
Hyperactive Member
You forgot another...You forgot one....
Does it have an internal combustion engine: Yes -- Does it have an electric motor for propulsion that provides full performance comparable to other vehicles in its class without starting the ICE: Yes -- Does it plug in: Yes = EXTENDED RANGE ELECTRIC VEHICLE
Does it have an internal combustion engine: Yes -- Does it have an electric motor for propulsion that provides full performance comparable to other vehicles in its class without starting the ICE, except for some times, in special conditions, but we don't talk about those, shhhhh: Yes -- Does it plug in: Yes = EXTENDED RANGE ELECTRIC VEHICLE...maybe
A question, does the EREV "standard" say anything about full performance compared to other vehicles in it's class? That's like saying an ICE is not an ICE if it doesn't have the performance of another ICE. Deeper and deeper we go into the rabbit hole.
So Plugin Prius == BMW i3 with range extender
It's just a "marketing ploy" to distinguish between them?
Pretty much. They're not in the same "class" of cars any more than a Prius is in the same class as a BMW 3 Series or a Leaf is in the same class as a Model S. But both the PiP and the i3 are plug in hybrids which correctly describes their motive power.
JRP3
Hyperactive Member
Exactly, we don't reclassify different ICE vehicles because of how they perform. Yugo, Corvette, Accord, all ICE's.
LOL! I am not arguing with you about the EREV name helping to eliminate confusion! I agree with you (and just said so above). This thread is plenty of evidence for that. I do find it useful in my own mind, but as a communication tool, it is detrimental.
I was just stating that I did not buy my Volt for its ICE capabilities, but for its EV capabilities instead. I am not going through that again, but you can reread our posts above or PM me if you wish.
GSP
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rolosrevenge
Dr. EVS
You do know that there have been standard definitions of serial hybrid and parallel hybrid right? If you want to drill down deeper then plug-in hybrid, you can use one of those.
I only stated my own interpretation of "full performance" and what I think the authors of the paper were thinking. To really know we would have to ask the authors directly. I really do think that "full performance" is not just "adequate performance," nor is it the maximum performance of some supercar. Instead it is the full performance that the particular automobile is capable of.
I saw the graphs in a car magazine or SAE paper. I don't remember where. The MT accel times you posted look right on the money equivalent to me up to 70 mph. Above 70 is not very important when you are driving a 35-mile car, so I would say the MT data supports the idea that EV and hybrid performance are identical.
GSP
Okay, I think I'm starting to understand... Thanks.
It doesn't matter why or when the gas engine starts burning fossil fuels. Who cares about that? What matters is how the engine is connected to the wheels. The only characteristic other than raw specification numbers like 0-60 mph and MPGe is the transmission style. Hmmm.
Wait. Hold on! That doesn't make any sense!
Sure we do. I see tables of performance numbers and specification attributes all the time in car magazines and on manufacturer's websites. Those cars are all conventional ICE machines so their engines run all of the time from beginning to end. I see table entries for 0-60 mph, 45-65 mph, 1/4 mile time and final speed, etc.
The new PHEVs have 2 sources of energy and so there are new characteristics that need to be added to those magazine tables to describe them. One new characteristic relates to when the fossil fuel engine starts up. EREV is a quick way to express that the engine never starts due to drivetrain power requirements or speed limitations. It's a simple and desirable attribute. If it cannot be met then there needs to be a footnote which describes in more details the various ways in which the engine might start before the battery runs out of charge. Other fields can tell the parts of the story that can be represented by numbers such as top speed, battery range, etc.
This is the straightforward definition in the GM SAE paper. It's not rocket science, just automotive engineering. Is anyone actually reading the paper's definition? It's clear in its own words that the definition of EREV is not dependent on the characteristics of the car after the range extender starts up.
DuncanWatson
Member
I will say, this is exactly the definitions I use. The others I view as marketing.
scottf200
Well-Known Member
Saw a presentation on testing vehicles at a EV monthly meeting recently. They have a Energy Systems Division that does testing - http://www.transportation.anl.gov/
They have a 2WD and 4WD (more recent) dyno. Would consider taking my Model X there to let them test it.
Anyhow, here is a page from an Argonne presentation classifying them.
Advanced Powertrain Research Facility’s Downloadable Dynamometer Database (D3) - http://www.transportation.anl.gov/D3/index.html
Presentation: http://www.transportation.anl.gov/D3/pdfs/ANL_APRF_DynoTestingReference_July2013.pdf
They have a 2WD and 4WD (more recent) dyno. Would consider taking my Model X there to let them test it.
Anyhow, here is a page from an Argonne presentation classifying them.
Advanced Powertrain Research Facility’s Downloadable Dynamometer Database (D3) - http://www.transportation.anl.gov/D3/index.html
Presentation: http://www.transportation.anl.gov/D3/pdfs/ANL_APRF_DynoTestingReference_July2013.pdf
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