Chevy Volt LCD Screen
It’s hard to believe after nearly three years of debate we have finally gotten some independent third party observations on what its like to drive a production-intent Chevy Volt in charge sustaining mode.
I thought it would be good to review and summarize what the reviewers said, seek some clarification from GM, and see what we all think of it.
Acceleration
LeBeu: low center of gravity and “sportier” feel when accelerating, not a sports cars, instant torque gives you responsiveness, will surprise skeptics
Brooke:sport mode delivers more oomph than normal mode
Handling
LeBeu:great handling that would surprise skeptics
Brooke: car feels solid and planted on the road, minimal body lean in tight corners, low rolling resistance tires provide excellent grip
Transition from EV to CS Mode:
LeBeu: transition is disconcerting, needs to be smoothed out, no fall off in power, jarring
Brooke:engine’s initial engagement is inaudible and seamless
Sustained CS Driving Requiring Power
LeBeu: N/A
Brooke: intermittent momentarily disconcerting engine revs with immediate disappearance of sound even though generator still spinning
Instrument Panel
LeBeu: loves green to yellow efficiency gauge, overall great
Brooke: N/A
Overall Impression
LeBeu: very impressed
Brooke: behaves admirably, extremely refined
I had the chance to discuss these journalist drives with Volt vehicle line executive Tony Posawatz who explained things the following way:
Both Phil LeBeau and Lindsay Brooke had wonderful drive experiences. I was in the car with both of them for their drives.
Neither was able to detect when the engine came on, much different than a hybrid. We are still fine tuning aspects of how the engine modulated under different load conditions.
We want to make it perfect. We have the unique challenge of balancing the customer pleasability, efficiency and regulatory requirements.
The engine has certain RPM efficiency points but does vary when you demand more power. Our work now is to feather in the RPM changes and refine which is simple calibration work.
The charge sustaining or range extending experience will be somewhat different to what people are accustomed to just like EV driving is a different experience.
Most of the time you will never know the engine is on.
+8
Nov 21st, 2009 (10:04 am)Woohoo!
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+9
Nov 21st, 2009 (10:16 am)Still waiting for the good Doctors drive.
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Nov 21st, 2009 (10:18 am)Could they not just keep the SOC (State of Charge) From falling so low that the Engine would not have need over rev just to keep the power coming? Say keep an extra 5% buffer ,let the SOC fall to 35% instead of 30% if the power requirement demand remains so strong that the engine needs to rev higher it can be done slowly. From what i understand quick revving of any engine wastes fuel.
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+6
Nov 21st, 2009 (10:22 am)Although the poll might be just a TAD biased with this population (G) how could the reviews be seen as anything but *progress* – and progress with the Volt is good.
Plenty of time to tweak by July 4, 2010.
Be well,
Tagamet
Let’s Just Get The Volts’ Wheels On The Road!!**********NPNS
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+2
Nov 21st, 2009 (10:32 am)Im looking forward to the day (hopefully in less than 10 years) when i can charge up my electric vehicle in my garage with a roof full of solar panels. Thereby eliminating two evils My electric company and Exxon.
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+8
Nov 21st, 2009 (10:41 am)An easy solution would be for GM to offer the driver a choice between max efficiency in charge sustaining mode, and max refinement — it’s all in the software. In max efficiency mode, the driver will have to live with a revving engine on occasion, as the engine will be aiming for max efficiency bands to sustain the charge in the batter. In max refinement mode, the engine could sustain the battery at lower rpms, which would not be in the engines’ max efficiency band (but it would be quiter) so the MPG will suffer slightly. Thus, let the driver decide.
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+3
Nov 21st, 2009 (10:44 am)Thankfully, “color choices” was not one of the questions.
They would have asked: “Why no Red or White”?
I still want one though. The “fun factor” is starting to show through.
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+4
Nov 21st, 2009 (10:52 am)Only getting excited NOW? (lol) It’s been a very long (and continuing) period of foreplay, but the, er, release is on the horizon.
Be well,
Tagamet
Let’s Just Get The Volts’ Wheels On The Road!!**********NPNS
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+1
Nov 21st, 2009 (10:53 am)People are probably expecting little things to tweak on a car that’s not out for a year so the little engine spikes were probably not a big deal. The point that they were very impressed overall is cool. I don’t understand this discrepancy.
LeBeu: transition is disconcerting, needs to be smoothed out, no fall off in power, jarring
Brooke: engine’s initial engagement is inaudible and seamless
This doesn’t make a lot of sense to me. I think that the first rule as a critic is that you never ONLY say nice things about what you’re reviewing. It just looks like you’re too easy to win over.
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+3
Nov 21st, 2009 (10:58 am)It does seem contradictory. The only thing I can guess is that the one critic was unsettled about the high rev that wasn’t related to the accelerator. That’s different than we’re used to and therefore “disconcerting”?
Be well,
Tagamet
Let’s Just Get The Volts’ Wheels On The Road!!**********NPNS
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+4
Nov 21st, 2009 (11:00 am)The Volt continues to look better every day!
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+2
Nov 21st, 2009 (11:02 am)The CS mode logic needs to be updated based on average power usage of specific period of time (maybe 2 to 5 mins). For example, if for next couple minutes the driver is driving fast or up steep hills, then the engine should determine the average power usage is high and then the engine slowly runs at high speed for the next couple of minute until energy storage is back in acceptable range. Another example is if driver uses high level of energy just for 5 to 10 seconds and then back to lower usage, the software should determine that it can continue run the engine at slower or just increase engine a small amount to recover the needed energy storage. This is what I would expect from a car like the Volt and surprised that the current software is not behaving like this.
Believe the problem in the design is that there is not a large enough buffer for the car to use. Also GM has said that when in CS mode they will not be recharging the battery but mainly providing energy for the car. Based on this the engine will have to continue to speed up and down frequently which is not desired by the driver or as fuel effective. GM has got to work this out. They have refined the car in so many other areas very well but this is still very weak area.
Do I believe GM engineers can work this out, of course.
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+1
Nov 21st, 2009 (11:05 am)“LeBeu: low center of gravity and sportier “fell” when accelerating,”
I think he means “feel”.
=D~~~~
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+7
Nov 21st, 2009 (11:12 am)If tweaking CS mode is the extent of the problems, then there’s nothing to worry about!
LJGTVWOTR
Has Plug? Have Sale
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+1
Nov 21st, 2009 (11:16 am)How did “Brook” know generator was still running? I don’t understand how engine noise can go away completely unless it dropped to lower RPM (1,600) vs say 3,000 RPM. Put a digital tach on the dash with a light that says RPM up arrow or down arrow. Slow down transition speed–problem solved.
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+1
Nov 21st, 2009 (11:35 am)initial reviews are fine but still they have to think its a 40k car. It has to be refined in that level.
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+1
Nov 21st, 2009 (11:42 am)Lots of people buy $40k cars when they could buy a used 2 year old Corolla.. perhaps if we look at the total cost of ownership?
Did you see the latest release on a rechargeable lithium air cell with 5 times the range of the Volt?
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Nov 21st, 2009 (11:46 am)Let’s see, we live in the age of computers, the internet and GPS. One would think that Volt engineers, slyly incorporating all three technologies in tandem, could almost design the car to anticipate uphill or (some) speed-up situations before hand, starting up and/or feathering the range extender engine accordingly.
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+2
Nov 21st, 2009 (11:54 am)Fantastic, but I’m a little confused by the apparent contradiction between the one reporters comment on the change to the CS mode being “disconcerting, needs to be smoothed out” and Tony”s remark that Neither reporter was able to tell when the engine came on. What’s with that?
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+5
Nov 21st, 2009 (12:09 pm)It is not lost on me at least to note that here we are talking about the refinement of charge sustaining mode on a car that has yet to be sold to a population that has never in the history of the planet had the opportunity to drive a viable electric vehicle. An outstanding accomplishment in such a short time span.
Where will we be in 18 months: greater range, greater performance, quieter operation……………..talk about boring!
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+2
Nov 21st, 2009 (12:12 pm)My two cents…
Here is the problem I think GM faces:
-If they want a larger buffer but still keep 40 miles EV they need a bigger battery= more $
-If they charge the battery up (much past 30%) then drain it, then charge it, all day every day= shorter life span on the battery
-If they just run the genset high or low most of the time= too many emissions/low MPG or not enough power
-Run the genset based loosely on demand= freaking out most drivers who are new to EREV’s
I think GM will just have to feather the RPM’s and drivers will have to get used to it.
The Volt is blind.
It doesn’t know what’s around the next bend. Doesn’t know if your almost home or about to take a big hill. Yes vs.2 may have GPS tied in but for now it’s more like the first automatic transmissions (may hunt for the right gear).
Still think that “sport” button that was talked about is the key. Hit it and the genset runs more with the accelerator peddle.
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+4
Nov 21st, 2009 (12:19 pm)Maybe have a chime alert sound when the engine RPM’s get above a certain level – like the ‘fasten seat belts’ ding heard in airliners – just to warn the driver that the generator is working hard. That should help calm down the unsuspecting drivers.
As an aside, I hope GM is going to be ready for Car and Driver magazine’s comparison test among $40K cars – pitting the Volt against BMW and Mercedes and the like. If the Volt can match them in handling and acceleration (don’t worry about top speed), which is a certain possibility, and if GM uses decent quality materials in the interior, the Volt will break through the mental barrier people have put into their own minds that the Volt isn’t worth $40K.
That kind of change in perception would be the best thing that could happen for the Volt, and GM.
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+4
Nov 21st, 2009 (12:49 pm)#14
I agree. On the whole, these reports eeem very positive and encouraging at this point in the car’s development.
Me too. Then we will really get the straight story.
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+1
Nov 21st, 2009 (12:51 pm)Perhaps it should be among cars that cost $32.5k.. and include total cost of ownership over 5 years.. hopefully depreciation wont be bad.
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+1
Nov 21st, 2009 (1:06 pm)Me too
JC NPNS
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+15
Nov 21st, 2009 (1:08 pm)Gentlemen, what we are looking at is a revolutionary, game changing vehicle for the 21st century. The only thing that can stop it now is Big Oil buying up GM and shutting it down.
What the GM engineers have done is truly above and beyond the call of duty. It has put America back in the forefront of automotive technology. The Volt excitement will now pass down to all those who manufacture, test and sell the product. They can take pride in what has been done and will ensure a quality in the finished product that will stun and dismay the Japanese.
Go Volt, go, GM, go Michigan, go Flint, go USA
NPNS
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Nov 21st, 2009 (1:09 pm)Some good replies today. Agree about the “sport” button and that sparked another idea.
What about a long haul and short haul button? It would alow the driver to tell the car I am driving short trips today. Say under some milage amount; 75 miles for example. Or the alternative is I am driving long haul 200 + miles so charg that battery up.
Giving the car a little information can help the system charge the battery in the most effecient way.
Thanks.
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Nov 21st, 2009 (1:10 pm)Correct NZ, I suspect GM is “bugging” the test drives to be praised later for having solved them.
That is a common strategy.
Regards,
JC NPNS
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+3
Nov 21st, 2009 (1:15 pm)The battery is already much, much larger than in a regular hybrid like the Prius. The Prius has a 1.3 kWh NiMH battery, of which they use 0.52 kWh as the buffer (40% of the total).
The Volt gets to choose which slice of a 16 kWh li-ion battery they want to use as a battery buffer. This Chevrolet video suggests they will use a 2.4 kWh battery buffer, which is HUGE.
http://www.youtube.com/watch?v=T_z3cjn9vJ4
Look at 2:05 on the video, the battery buffer zone looks like 1.5 tenths of the battery (look at the lines dividing the battery size into tenths).
This is 30% SoC down to 15% (15% is probably the hard, lower limit).
They will be draining 80% to 30% just once a day for most drivers (maybe twice, for commuters that recharge at work).
Then, lots of tiny charge/discharge cycles within a small slice of the large battery (30% to 15%), if they enter Charge Sustaining mode. Yes, this will shorten the battery life some, but much less than charging/discharging within a 50% SoC range (the Prius does constant charging/discharging within a large 40% band of its tiny 1.3 kWh battery).
The question is not, isn’t the lifetime shorter ?
The question is, what is the lifetime ? If this arrangement still yields 10 year lifetimes, then fine.
If the maximum power of the genset is 71hp, and the engine runs much of the time at even lower RPM’s, I don’t think MPG is a big worry. How many sedans with a 71hp engine do you know of ? It’s not exactly a gas guzzler. And with the large battery buffer, the power demands can be met by building up a reserve, using it, building it up again, etc… Using a tiny 71 hp engine, but using it smartly, should give very good MPG and emissions.
Yes, most drivers are new to EREV’s
Since the ICE is not connected to the wheels, the vibration and noise is probably much less than a regular car.
They say when the engine comes on, it’s imperceptible, which is a good sign.
I wonder how much noise suppression materials the Volt can put around the genset ?
Remember, the slower the battery buffer is recharged, the more potential situations where there is a power demand, but the battery buffer is not yet filled.
But since the battery buffer seems to be huge (4.6 times the size of the Prius buffer), perhaps the nice, feathered RPM ramp up will be “pleasing”, plus “good enough” in terms of power available when you need it.
I think the large battery buffer is a definite advantage of the Volt – that 400 pound battery is not just useful during Charge Depleting Mode.
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Nov 21st, 2009 (1:24 pm)It sounds great and I was particularly interested in the reference to a “sport mode”. It was disturbing that regulatory considerations are playing a role in the over-revving problem. Regulators need to understand that the success of this technology is critical to solving our energy problems. They should consider allowing an optional added 5% battery buffer that would allow the engine to come on at a low bt energy efficient rpm and fluctuate with power demand up to the torque peak, only released for revving to the horsepower peak when battery charge falls to the 30% level. This optional mode could be accessed by a software “switch”. Thus those who will accept the disconcerting effects of maximum economy mode can have it and those who prefer excellent economy but with more natural transitions can have that as well. Some of us, of course, would like a third option: sport mode.
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+2
Nov 21st, 2009 (1:27 pm)Very *very* exciting times. I wish we could see how this whole situation plays out say 5 years from now. Will we be a niche? Will this snowball, and with other mfgs become a huge factor in transportation. What developments in battery tech will spring up and be fielded in that time?
I could go on, but you get the idea. It’d just be neat to know.
Be well,
Tagamet
Let’s Just Get The Volts’ Wheels On The Road!!**********NPNS
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+1
Nov 21st, 2009 (1:27 pm)Concerning the driver display, I feel it would be useful to have an option to allow the driver to select the speed readout and some other information in digital, analog, or both, kind of like in various computer racing games I have seen. This could look something like the electronic flight instruments in many aircraft “glass cockpit” displays that show a CGI dial arc and needle with a rectangle in the center with the numerical readout. I imagine it as something that could be selected on an “Options” page accessible through the center touch screen.
Also, I feel encouraged to see that the photos in the articles show the integration vehicle with the production-type front and rear bumpers, lights, etc. (One thing I have noticed as an identification feature between the integration vehicles and the production show car, other than the hood line, is that the bottom gray panel immediately behind the front wheel is level with the lower edge of the door on the show car, while it comes back up to match the rest of the trim on the IVERs.) I guess I prefer the show car’s slightly smaller rearview mirrors, but that’s just a minor nit in the big scheme of things.
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+7
Nov 21st, 2009 (1:41 pm)This is very promising. It will be simple for them to update the engine management to change RPM more smoothly. People will have to get accustomed to the engine being disconnected from the accelerator. I hope GM does not try to emulate a standard ICE vehicle. That’s not the point here.
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+1
Nov 21st, 2009 (1:45 pm)I think that it’s been reported that the dashboard instrument panel will be “customizable”.
Be well,
Tagamet
Let’s Just Get The Volts’ Wheels On The Road!!**********NPNS
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+2
Nov 21st, 2009 (1:47 pm)#33
I totally agree. +1
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+2
Nov 21st, 2009 (2:04 pm)I predict this technology will really take off as GM gets the productions costs down. This is a superior technology, it is more efficient for equal performance, there’s no range anxiety associated with it, and it diversifies the fuel required (electricity vs. gasoline/E85). Plus, the cost/mile using electricity can’t be beat. Besides, I’ve never been interested in spending my $ on GM products, nor have I been overly impressed by their technology. To date, I’ve only purchase Honda, Acura and Toyota. That’s not the case anymore, I’m impressed by the Volt and I don’t think I’m alone – I want one. That has to be worth something intangible.
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Nov 21st, 2009 (2:04 pm)Where is the fuel gauge on the screen. I hope it indicates how much fuel (e.g. 4.8 gallons) remain not an analog gauge of fullness. The screen looks pretty busy to me.
For Lyle’s drive (if it hasn’t happened already) it would be neat to hear about:
-Range remaining and amount of gas left in the tank
-Operation in CS mode at stops
-Operation during long, hard accelleration
-Operation at 70mph steady highway
-Cruise control operation (Is there a max efficiency that’s based on power usage not a set speed)?
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-1
Nov 21st, 2009 (2:06 pm)(Quote)
+3
Nov 21st, 2009 (2:20 pm)One thing is for sure: the first Volts will be the least practical ever made. While the first models will be over designed in some ways that they will cost reduce later, other aspects will only improve. Battery tech, genset, accessories, etc will only improve as production matures. Paradigm shifts like this open up tremendous opportunities for improvement through new innovation and iterative developement.
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Nov 21st, 2009 (2:44 pm)I read the criticism as, once you get to the top of the hill and take your foot off of the gas, the noise is disconcerting. The suggestions of changing RPM smoothly or feathering would be inapplicable for suddenly decreasing power needs…just speculatin’. Speculatin’ sounds like it could mean either waving my arms wildly without reason, or spitting in the wind
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Nov 21st, 2009 (3:10 pm)Do you have a link Herm? The only article I found was dated back in May of this year.
Happy trails to you ’til we meet again.
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Nov 21st, 2009 (3:15 pm)A big amen to that and a hooting Hallelujah! +1
=D~
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Nov 21st, 2009 (3:26 pm)GM PR must have debated long and hard over how and who. And they should. These two reports are solid steps if GM is to elevate excitement to oohs and ahhs. We would appreciate knowing if these test VOLTs in the reports had Goodyear Assurance Fuel Max tires which Goodyear claims are the exclusive fitment for the 2011 VOLT. We’ll further assume LeBeu and Brooke will drive VOLTS periodically with progress reports …
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+1
Nov 21st, 2009 (3:59 pm)From the NYTIMES review
” the Volt’s electric drive has no whine”
Which was one of my concerns. Awesome that there is no toy car whine.
I’m also very excited about the reviews of the handling abilities of the car!
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Nov 21st, 2009 (4:24 pm)I dont think I can link it or it will get moderated, check the Green Car Congress web site, it was posted today.
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+2
Nov 21st, 2009 (4:57 pm)There is a very simple reason for one reviewer to say that the transition to ICE mode was jarring and yet the GM guy said that neither noticed when the ICE came on. The reviewer actually missed the moment when the ICE came on and what he found jarring was the RMP step up that the other reviewer also noticed. So it seems to me that:
Having the ICE come on is imperceptible
The ICE will step up its RPM when it needs to generate more power but this behavior is not well correlated with the accelerator. You probably get better mileage with the step up in RPM rather than feathering it up but not by much and GM will probably make adjustments to this and the overall driving performance will be the same.
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Nov 21st, 2009 (5:05 pm)The size of the bufffer is not the issue. This example shows the issues
Volt at stop light in CS mode waiting to get onto a freeway
Slow Left Turn
Full Acceleration 3 seconds
“Fast” Right Turn Loop 5 seconds
Full Acceleration 5 seconds
Merge with Other Entry Traffic 4 second (2 second brake with 1 coast, 2 brake, 1 coast)
Half Acceleration 6 seconds
Merge Highway (Coast + 2 seconds Full Accerelation)
Coast on flat surface 5 seconds
Go up Hill 35% Acceleration (due to hill) 30 seconds
Response Modes:
“Follow Pedal” – What the point? Won’t be any better than a normal car as your still varying the ice based on power requirements of the moment
“10 second delay” – Generator never spins up completely till your halfway up the hill. Meaning you’ve probably dug significantly into your buffer and thus have reduced hill climbing ability. Not to mention that its really strange compared to an ICE car that would have shifting/rpm field day
Solution (I think)
Multistage damper. Lets assume that 30%–>15% is the SOC. At various states along that SOC degradation, there is different responses. From 30%–>25% a fine feather mode is what happens. At 25%–>20% the mode “pre-guesses” the driver to provide slightly more than requested power. At 20%–>15% generator runs at max power until the SOC is back into the 23-24%+ range.
From the descriptions of the reporters, I think thats exactly what happened. They went into the test and pushed the Volt around…. you know how everyone drives if you have no traffic and no concern for fuel efficiency. Then they hit the “25%” barrier and the ICE went from supply slightly less power and power requirements smoothed over several seconds (and not audible) to supply more power than required smoothed over several seconds (and thus very audible in comparison). If they had continue to push the Volt around (probably for a long time, because the ICE is acting now to oversupply power) they might have hit the 20% barrier and experienced the “emergency” recharge.
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+1
Nov 21st, 2009 (5:41 pm)I figure that if the airplane manufacturers can figure out how to reduce the noise of their jet engines, GM can probably do the same thing for the Volt.
http://www.gtri.gatech.edu/casestudy/reducing-noise-micro-honeycomb
I hope they succeed in optimizing when the engine kicks in at higher r.p.m.s AND they add good sound deadening materials to the Volt. So quiet you don’t even know the Volt has an IC engine hopefully. The big question of course is … how much would it COST to get rid of IC engine noise and vibration … say 95% of it.
http://www.secondskinaudio.com/products/Sound-Deadening-Materials.php
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Nov 21st, 2009 (5:46 pm)I wonder if there will be a remote start option? This sounds silly at first, but if it is winter time and the car has been sitting at 15 degree temperature for 8 hours and if it takes a few minutes of running the ICE to warm the battery, then it would make sense. I can even see setting it on a timer, but have the car call you on the cell phone to confirm that you are ready and then you can confirm or postpone. Because of the computer there are lots of cool options.
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+2
Nov 21st, 2009 (5:53 pm)Lyle,
Seldom do you make mistake in your presentation, but this time you did. Who ever said IV version autos, are “production intent” or even “near production intent”? They are most certainly not. They are still engineering testbeds, by and large.
I would like to see the PPVs versions and then the later versions of those PPVs, to determine what the true “production intent” vehicles are like.
It would appear to me, that the IV version past the exam with flying colors. The VOLT EREV appears to be already smoother than a Third generation production Prius.
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Nov 21st, 2009 (6:08 pm)Careful.
Semantics are a slippery slope.
“Validation” builds are what they have been officially called. Setting of expectations is the point. For a $40k vehicle, they are likely to be very high regardless of label or build level.
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+1
Nov 21st, 2009 (6:19 pm)I believe that the battery is warmed simply because it’s plugged in. There ought to be any number of temperature management processes that should be built right into the car.
Be well,
Tagamet
Let’s Just Get The Volts’ Wheels On The Road!!**********NPNS
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Nov 21st, 2009 (6:45 pm)GM may alter the nose and rear quarters of the Volt. Wonder if they will add elements from the Ampera design? What will the production lighting look like? Anyone notice a third brake light?
=D~
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Nov 21st, 2009 (7:00 pm)Watching this website is like being a fly on the wall at the Wright Brothers bicycle shop.
And remember, it was less than 70 years from the time they first left the ground until men walked on the Moon.
What wonders may come!
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Nov 21st, 2009 (7:16 pm)The final software for controlling the ICE will be more art than science – it will be a balance between “feel”, MPG efficiency, adequate power in most situations, “sound”, battery lifetime as based on accelerated testing, etc.
But whatever GM does, the available large buffer gives them more choices. They can turn off the ICE at red lights, because a 15% buffer gives them much more energy cushion than a 3.25% one (the size of a Prius battery buffer, 0.52 kWh). They can use lower RPM’s, and thus a quieter ride, knowing that the longer recharge to 30% SoC (full battery buffer) is not as serious an issue, because they still get to discharge down to 15% if needed. Whatever the design decisions, having that large buffer available has increased their software possibilities.
Even if they choose to go with a smaller battery buffer for some reason, it will be because they want to, not because they have to (unless the battery endurance tests indicate the large buffer is costing too much in lifetime degradation). I hope the lifetime tests are fine, and GM shows us some really creative software for turning all this new hardware into a great car
And they do vary the ICE rpm based on the power requirements of the moment, it is more energy efficient than going through the battery buffer (charge conversion losses, discharge losses). But they only have a few, preset RPM points, for efficiency sake. Most RPM’s will be less, or more, than the power requirement of that second. So, grab some power from the battery, or put some back in. Maybe keeping the battery at 22.5% SoC is the “sweet spot”, so they will use lower, quieter RPM’s for awhile, and drain the battery, then put energy back from regen braking up to 30%, etc…
Why just 3 SoC regions (30-25, 25-20, 20-15%) ? Why not 10, or 100 ? Why not look at the speed for the last 10 seconds, or 1 minute, or 5 minutes to estimate if the car is in the city, highway, hills, etc…
The point is, this software can quickly become very complicated and the end result might be quite elegant. The big battery buffer allows much more to be tried.
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+1
Nov 21st, 2009 (7:38 pm)(Quote)
+1
Nov 21st, 2009 (7:41 pm)I hope you want to charge up your car in the daytime because you are NOT going to be able to charge your car up at night. Most people will want to charge up their cars at night for their daily commute. Despite what some solar enthusists tell you, it’s not going to be possible to charge up over night on Solar.
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Nov 21st, 2009 (7:44 pm)I hope you want to charge up your car in the daytime because you WILL NOT be able to charge up your car at night with Solar Power. Most people will want to charge up thier cars at night during low load times for the power company. With solar that’s not going to work. Sorry-no sun ,no power.
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Nov 21st, 2009 (7:48 pm)I’m going to charge my Voltec at work. Look at it as a 10 cent per hour raise. (yummy)
=D~
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Nov 21st, 2009 (8:50 pm)Not sure that I will be able to keep it plugged in at work. It would be nice, but I’m not counting on it. I AM right at the 40 miles per day round trip. But the parking garage at work is not heated. It’s my understanding that the ICE will come on to warm up the battery, per Rob Peterson.
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+1
Nov 21st, 2009 (8:54 pm)The two aren’t contradictory. The reporter couldn’t tell when the engine came on, but could tell it revved up when it was already running.
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Nov 21st, 2009 (8:57 pm)Is the benchmark $40K or $33.5K? There is a $7500 federal credit. States may tack on more. In my case it’s another $5K.
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Nov 21st, 2009 (9:00 pm)Let me explain what is happening. The acceleration from 0 to 60 miles takes 10 seconds. If you floor pedal then you load demand around 100 kW for 10 seconds and max power consumption is 100kW/3600×10=0,3 kWh. In reality is less because the max demand is only during first second. It is no more than 0,1 kWh. Part of that demand will be covered from generator itself. So you have SOC fluctuation in the range of 0,1 KWh. It is roughly 0,5% of SOC. AND THAT IS MAX THEORETICAL SOC FLUCTUATION REQUIRED. iN THAT CASE ENGINE SHALL RUN ON MAX CAPACITY DOUBLE TIME. SO THAT MEANS THAT EREV TECHNOLOGY GIVES YOU EFFECT THAT ENGINE ROARS DOUBLE OR THREE TIMES LONGER (lets say max 10 seconds more) THAN ACCELERATION LASTS. AND THAT ABSOLUTELY NORMAL AND YOU HAVE TO LIVE WITH THAT. When you have conventional car roaring lasts shorter period of time. When you have EREV or locomotive the roaring doesn’t matches acceleration. We are not having fluctuation 5% of SOC or 5 minutes to level SOC because it would be total mess.
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Nov 21st, 2009 (9:08 pm)I seem to remember a timer warm up on utility power. It makes a lot of sense CD range wise to have the car warmed or cooled prior to unplugging. The remote or timer start burning gasoline only increases fuel use and may be resisted.
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Nov 21st, 2009 (9:12 pm)True! I believe the Prius “shudder” is mainly related to the direct connection between the engine and the wheels. A buddy has one and it is quite noticeable. It’s most annoying when the engine shuts down during slow driving.
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Nov 21st, 2009 (9:19 pm)http://news.yahoo.com/s/ap/20091120/ap_on_re_us/us_electric_elk_horn
Take Care
Arch
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Nov 21st, 2009 (9:37 pm)Every one that is confused with the reporters contradictory statements in regards to CS mode, just use a little critical thinking.
Lebeu is obviously talking about when he accelerated hard and the generator kicked into high gear to make up for the power loss.
Brooke is talking about when the generator initially engaged, which is what the original question was and what Tony was referring too, that neither one was able to detect.
Both of them agree that when the generator kicks into high gear under high power load, the noise is “disconcerting”.
Hope that clarifies,
BTW the review is great news, the transition from EV to CS mode is flawless, the car is sturdy and handles great, it’s sporty and accelerates well and all of the dashboard controls are well refined and easy to use. The only thing that remains is how to feather the generator into higher gear when under high power loads, which is mainly just software and easily correctable by July.
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Nov 21st, 2009 (10:30 pm)Really, just $27.5K ? What state are you in ?
Plus, GM has not finalized that $40K. Perhaps they will make it $39K for PR reasons, or warranty optimism…
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Nov 21st, 2009 (10:35 pm)I think the regulatory consideration is ‘what will the EPA mileage sticker display’ more than anything else. GM is treading a fine line to get good performance and good customer experience while also getting maximum cred for their EPA sticker. If the EPA city mileage is way below 230mpg this is a credibility problem.
We shall see pretty soon. GM will have to submit cars well in advance of launch for crash and EPA testing.
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Nov 21st, 2009 (10:44 pm)Or, they could use a low RPM, like 2000 rpm which is not the full 53 kW, but much quieter, take the rest of the power from the totally quiet battery (which is just a small dip into the battery buffer), and then slowly recharge the battery buffer up to where they want it to be by running about 500 rpm above the required power point for the next minute or so. GM has lots of options to make the car quieter, more “powerful” in most situations, or more fuel efficient, etc. If they don’t like the engine roaring for 10 seconds, they can easily change it. It is all a tradeoff in software.
As for “max theoretical SoC fluctuation required’, you forgot about situations like driving up a hill, into a headwind, at high speed. Accelerating 0 to 60 mph on a flat road is just one scenario. A large battery buffer gives you great flexibility, and a long time to recover the energy at higher-than-needed engine rpms.
And whatever they do, it looks like they will have at least three “Modes” – Normal, Sport, EnergyEfficient. These modes will run the ICE differently, in software.
They could easily offer even more modes, in software/firmware updates, or a Driver Preferences screen. The possibilities are MUCH greater than for a regular ICE car, or even regular, small battery buffer hybrid.
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Nov 21st, 2009 (10:54 pm)Solar in most home installations is pushed back to the grid. You can basically say you are using your own power even though it is not the exact same electrons.
If it’s done correctly, they would be paying you more (on peak) for your solar electrons than you pay (off peak) for the their hydro, wind, NG, coal, nuclear etc electrons.
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Nov 21st, 2009 (11:55 pm)TCO : Will be high for EV and EREVs because electricity is also not free and the resale it keeps will be low. Look at how nissan plays ( 20k 100 mile EV )
I don’t know whether you know that the production ready technology is almost 10 yrs old. May be if they can make rechargeable lithium air cell till production ( its better to say eestor will be there in 10 yrs ).Toyota was saying on another battery technology which goes 10 times that current storage capacity but the last line was it will take min 10 year to reach production.
When stuff goes without production level refinement and value for money , people call it junk and not value for the money ( I have shaken the tree in front of my house a lot time but 40 k didn’t fall from it, so it needs the refinement of a 40k car for me to spend on it )
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Nov 22nd, 2009 (4:37 am)People really need to get a grip on this
Fuel for a typical 25 mpg car over 100,000 miles is 4,000 gallons.
If we are lucky enough to have economy recovery, you better believe 4.00+ gasoline is comming back.
16,000 dollars is quite a bit for fuel. Even a 50 mpg car will require 8,000 for fuel.
Electric? 25,000 kWh seems like it might be expensive. Even at 0.25 dollars per kWh, that’s still only 6,250.
Add in reduced oil changes, brake changes, etc and it’s pretty fair to say a full EV has a good 2,000 TCO advantage over a hybrid going all the way upto 10,000 TCO over basic cars like Civic/Corolla.
If you cross shop a Volt against a BMW 3 series… Even the cheapest 3 series will be more than 10,000 more expensive over 100,000. Only car I know over 30,000 that really has a chance to go toe to toe on TCO is the A3 TDI…. If your extremely lucky and don’t require major repairs.
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Nov 22nd, 2009 (8:05 am)Steel,
If your going to look at TCO, there is no way that the Volt can win this game today.
You have to factor in the other issues:
1) Maintanence: Remember the Volt gets to have the luxury of both a BEV and ICE. I see no way that you can expect that maintanace will be less over the life of the car. Ever price out one of those electric motors? How about the power electronic section, these are going to be very expensive.
2) Battery degradation: It is not a matter of if, its a matter of when. I drive my vehicles for a minimum of 12 years, and usually 200,000+. GM has already pulled back on the original warranty period, so they know what typical life will be. Replacing a battery in a 10 year old vehicle will be a hard pill to swallow.
3) Resale: Your in for a surprise, when you try to sell your 8 year old Volt, and the battery has maybe, 2-4 years of full service left.
TCO is not going to win any supporters over for the Volt.
Yes, gas prices can and likely will rise again, but who says electricity will not rise as much or more? No crystal ball comes with a purchase of a Volt, so we need to base it on the facts of today, and attempt to predict as best we can, what tomorrow brings.
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Nov 22nd, 2009 (8:39 am)How about a full blown cross country road test? Yes the Volt is made for the 40 mile commute, with a safety net. In that regard I have no doubt that it will be a wonderful machine. Lets say I buy one of the first ones on EBay for 55+k in SoCal and have to drive it home. Would I be happier in a Prius, or HHR? Could the Volt replace the second (vacation) car? Lutz said the Volt should do 100mph no problem.
With narrow tires and heavy weight snow should not be too much of a problem for the Volt. However I would stay off of dirt roads in the spring. In mud, I think the Volt would sink. Other than that I think the Volt would be multifunctional.
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Nov 22nd, 2009 (3:00 pm)Oregon. The rule is $2500 plus $417 per kWh of battery capacity up to a total of $5K.
The stupid part is while one part of the state is handing out rebates, the highway department is busily figuring out how to tax fuel efficient vehicles by the mile.
I figure just let electric vehicles use the roads for free and call that the subsidy.
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Nov 22nd, 2009 (3:07 pm)The Prius already disproves every one of the elements of point 1 you’re making.
The engine used the way the Volt does lasts far longer. Idling and start / stop usage are hard on an engine. The Volt engine won’t ever idle and will start and stop a lot less.
The motor? Failures of the motors will be very, very rare. Think of some of the motors you own… how long do they last?
The power electronics? A few of those fail on the Prius, more than the motor; but failures are still far from common.
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Nov 22nd, 2009 (5:03 pm)I would agree with having 3 mode. Max efficiency Normal and Sport. Computer running every thing as far as the ICE is concerned. Let the Driver pick. While you are at it make a Mode to charge a stranded EV. Of course that might not be practical because, I bet every Different EV is going to have a different Plug. Or the Safety concerns are going to be to great.
Wouldn’t that be good PR for Chevy Volt.
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Nov 22nd, 2009 (5:30 pm)Im looking forward to the day (hopefully in less than 10 years) when i can charge up my electric vehicle in my garage with a roof full of solar panels. Thereby eliminating two evils My electric company and Exxon.
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I have the electric PV in place, did not pay any electric from Sept 08 until June09. Pushed electric to grid during day and comsummed it at night. It will be interesting to see what FPL works out with state when we get smart grid. Will they trade more than even since I’m producing electric during peak cost and using it at minimum.
Can’t wait to get my Volt to go with it. (G)
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