Hate the Volt?

In Re: Post 13, Item 4: Steamed okra is horrid. It's like mucus. But okra in soup is really good. No more slime.

 

I have the same issue with it, it's hard to take it seriously given how much it's been hyped up, from its final cost (much higher than initial claims) to mileage, to gas range, to, um, "fibbing" about how it's always 100% only electric in all conditions, etc. And while doing this their CEO actively badmouths another car that has already proven itself in the market.

It's also silly that mags like motortrend give a vehicle car of the year when hardly anybody is buying them.

 

SALES have always been the ulimate gauge of success, since aspect of design merit are often hyped initially then conveniently forgotten when not achieved upon delivery.

Those mags and former executives don't have that kind of accountability... nor the concern that some of us express.

If traditional vehicle production is not being replaced by the new technology, what the heck is the point?
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Can I hate my own car for having a cruddy heater? Is about my only complaint. I never followed the car when it was a concept, or anything else other than making fun of people for wanting to own hybrids/EV's back when the Volt was still on the drawing board... Kind of ironic how things pan out. I am unsure of all of GM's promises.. I know when I had my SRT-8 Chrysler promised to release the 6.4L 525hp Hemi, and years later they finally delivered a watered down version. Personally by the time I started following the Volt with interest a few months ago I got basically what I have been reading about.

I will agree though that the gas mileage is also horrible in Charge Sustaining mode... The best I have ever witnessed personally is upper 20's. Not sure if this is because the engine is still wearing in a little or what. Certaintly not anywhere near the 37mpg on the sticker though, and the same ball park as my fathers Cruze. In 1200 miles though I have used 2.3 gallons of fuel though, so I am happy overall. Do think they could have put a V-twin in, or a 3 cylinder to power the generator...

 

I just posted my lifetime (such as it is) numbers over on GM-volt.com.
I drive mostly 55-60 mph with minimal climate controls. I'm not sure how you are driving your car. Some of the difference could certainly be break-in. Some of it may be that you are running the gas engine only for short distances at the tail end of your trip. The mileage also varies somewhat over shorter distances because the Volt may run the engine for awhile, then use the battery a few miles, then gas etc... If you don't average that out over enough miles then your actual "gas-only" mileage can vary quite a bit depending on when you happen to end your trip and what part of the battery buffer you were operating in.

Here are my numbers:

2011 VIN #42
December 21, 2010 delivery
13654 total miles
08136 battery miles
00103 total mpg
00042 gas-only mpg

30 kWh / 100 miles approximate EV efficiency (120v charging)

That includes a 1,000 mile round trip to Los Angeles and a 2,800 mile round trip to Western Canada (93% gas, 7% battery, 45 mpg total, 42 mpg gas-only).

If you take out the trip to Canada I would be at 150 mpg. My typical weekday drive is 25-30 miles with an occasional weekend round trip of 80-100 miles.

 

Thanks for posting that data Jeff. It's always good to see some real world user data.

 

I certaintly do not drive the Volt like the Prius unless I am going outside of my EV circle. If I do that then I try to drive more conservatively. Might be because the engine never has a chance to warm up. The farthest I have ever gone on the gas engine is probably 25-30 miles or so once. Most recently was on the drive to St. Augustine.. We went 36.4 miles on the battery, and about 7mi on the gas engine burning a total of 0.3 gallons indicated on the display.. After a little math it comes out to about 23mpg. Started Wednsday we will be driving both cars from here to Norfolk. I intend on doing an extensive thread here comparing both cars (I know the Prius is going to win by a long shot, just a matter of how much) to overall efficiency. My wife will be driving the Prius though, so maybe I do have a shot beating her mpg with the Volt.

 

Up until last weekend I was indifferent towards the Volt. Then I opened my newspaper and saw a deal too good to pass up.

I've only logged 200 miles so far and I hate to say it, but it feels so much more solid behind the wheel the Prius. The drive and features just blow it out of the water.

 

The Volt,like this thread, is boring.Over-hyped, over-priced cars are not exactly novel.

If you want to start a GM hate thread I am sure I could spill some bile.

 

Lots of talk about how wonderful the Volt is. If someone wants to give me the opportunity to drive one, I'll report on my experience. And if anyone thinks I won't be honest because I hate GM, note that I hate Nissan also, after the dishonest and disrespectful way they treated me. But I still tell people, on line and in person, that it's a great car. Since the Volt is a two-mode car, I'd want to drive it both in EV mode and in CS mode, on surface roads and freeway.

 

Send me a PM the next time you'll be near Delaware.

Otherwise, your local dealers should be getting demos by now.

When/if you go also be sure to test it in both "D" and "L" and normal and sport modes.

 

Them's fightin' wurds!

GM has carefully avoided ever referring to the propulsion system design in Volt as the next generation Two-Mode. That would wreck their promoting it as an EV.

Enthusiasts praise GM for being so amazingly transparent throughout the development process... even though the information about having direct-drive and the MPG after depletion were withheld until right before rollout began.

That knowledge makes Volt a plug-in hybrid, not an EV.
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Technically I suppose it could be thought of as Three-mode, it starts as a pure EV (no blending), then it enters CS mode as a series hybrid (to the best of my knowledge what it was always promoted to be), and in a very limited circumstance it has the ability to augment itself with some parallel hybrid operation.

I'm driving 50 some miles today and it will be all EV (with charging at work). People need to be told they can do that in this car.

 

Thanks for the offer. I doubt I'll ever be within 500 miles of Delaware. I'm very reluctant to either pretend to be an interested potential buyer, or to say to a dealer "I am not going to buy the car because I already have a gas car, an EV, and two more EVs I'm trying to sell, but could I test-drive a Volt?"

It can drive on electric; it can drive on gas. That right there are two modes. And then gwmort tells us below there's a third mode.

So not only do they have an electric motor or two, and a gas generator, but they also have some sort of drive train direct from the gas engine to the wheels??? That would seem to introduce unnecessary complexity, weight, and potential for breakdowns.

How do they introduce the direct drive into the mix? Is there a clutch that connects the engine to the drive shaft?

If it were not for that, I'd be inclined to allow them to call it a range-extended EV. But with that, it becomes a hybrid. Or the hybrid of a hybrid. It's a REEV hybridized with a gas-electric hybrid.

BTW, most new cars do pretty well when new. And most new-car owners, having taken the plunge, are really happy with their new car. And a car as different as the Volt will mostly only attract committed enthusiasts at first, especially with the big price tag, and such people will be even happier with their new car due to their prior commitment. How reliable the car proves to be over the long haul will play a big part in its general acceptance. Toyota has a long history of reliability. GM's history is not so good.

BTW, I drove the Leaf in both normal and eco modes, and was not impressed with its performance in eco mode. I've never driven my Tesla in performance mode. Standard mode is scary powerful.

 

It depends on how limited 'very limited' is. I would describe "combined 2-motor extended-range" (as GM engineering refers to it) as being common at speeds above 40 mph. The EPA highway test cycles are in this mode about 50% of the time, according to a GM paper at the 2011 SAE conference. This mode is more prevalent at higher speeds and lower torque demand.

A key difference from the Prius design is that it is less noticeable to the driver. Lower speed driving is single motor "serial hybrid" so you don't feel any mechanical interaction with the gas engine. There is no noticeable change in driving feel if the battery buffer is at a low point of charge (other the hearing the gas engine). On a Prius you can feel the CVT gearing ratio change at lower speeds as the car focuses on generating electricity to recharge the battery and the car becomes less responsive. The Volt always drives like a full-power EV even when it is in hybrid mode.

 

I'm not much of a gear-head, mfennel or Scott could explain it better but there are a couple of clutches. Its one of the main things John and some of the purists on here complain about because GM stated repeatedly there would be no direct drive, then it has some.

To clarify it has no direct drive in CD mode.
In CS mode it will only engage the extra clutch for some direct mechanical assistance under high load conditions, under most conditions in CS mode the ICE acts only as a generator.

It does add complexity, but it is supposed to provide a 10-15% efficiency boost for operation in the power range where it is used. (I believe over 70 mph)

I also wouldn't be concerned with asking for a test drive; they'll just try to sell you a Cruze afterward anyway...

 

The Volt has two modes: full-power EV mode and hybrid mode.

Hybrid mode has two flavors: serial and serial/parallel.

When you start off with usable charge in the battery pack the car is in full-power EV mode and the driver display shows a prominent battery charge status icon. The gas engine is not used during normal driving even during full acceleration and at the highest speeds (100 mph).

When the usable full-power EV capacity of the battery has been drained (10.4 kWh of the nominal 16 kWh pack) the Volt switches to hybrid mode and the driver display animates a switch from a prominent battery status icon to a gas tank status icon.

In hybrid mode, the Volt typically begins with the gas engine off until the speed of the car reaches about 30 mph at which point the gas engine is started. This helps to mask the engine noise with background road noise. At speeds below around 40 mph and during strong torque demand (strong acceleration) at speeds below around 75 mph the Volt uses a serial hybrid strategy where it drives the car using its 149 HP electric motor. In serial mode it generates the average electricity required to balance the battery buffer with the gas engine which is only mechanically connected to a 74 HP (55 kW) generator.

At speeds above around 40 mph and at lower torque demand the Volt often switches to a serial/parallel strategy similar to the Prius. It does this by using a clutch to mechanically connect the gas engine and generator to the Ring gear of a planetary gear set. Together with the 149 HP motor connected to the Sun gear, this implements an electrically controlled CVT which drives the wheels which are connected to the planetary carriers.

The Prius also uses a planetary gear set to connect the same components (gas engine, large motor, smaller motor/generator, and the wheels) as an eCVT but with different details and without the ability to unclutch the gas engine and generator from the planetary gears (and therefore limiting the Prius's EV-only speed due to RPM limits on the smaller motor/generator).

The Volt is also capable of unclutching the smaller motor/generator from the gas engine while clutching it to the planetary Ring gear. This allows both the large and small motors to drive the car on battery power more efficiently above around 60-70 mph because both motors can turn at lower RPMs when their output is combined.

 

It's certainly elaborate.

The engine doesn't connect directly to the output shafts. It's connected to MG1, which supplies power to the ring gear of the planetary. MG2 must also be turning for the car to move forward. Whether this is "direct" or not seems to depend greatly on one's view of GM.

Anyway, the clutches are already there. One connects the ICE to MG1. The other connects MG1 into the ring gear (that's how you get two motor electric operation).

If you really care to understand what's going on, I offer this 36 minute YouTube video of Pam Fletcher, the Chief Engineer, Powertrain on the program, explaining the architecture and operating modes (from a journalist's handheld camcorder, unfortunately):

[ame="http://www.youtube.com/watch?v=d9-9atMw6Zs"]2011 Chevrolet Volt, Powertrain - YouTube[/ame]

Jump to 30:00 to see an animation that includes a cut-away of all the components working.

 

This is a misconception due to some inaccurate media articles and misinformation in Wikipedia's Volt article (probably a circular misinformation loop). Actually, the Volt prefers to be a serial hybrid under high torque demand at speeds lower than 75 mph or so. You can see this in the efficiency maps in the link I mentioned in an earlier post.

Here it is again:

CS mode: ~2200 RPM, ~1500 RPM, then "CD mode"

Here is a nice high-level description of the Volt transmission modes posted to a GM-owned blog meant for training dealer mechanics. It also has a nice illustration of the transmission innards:

Voltec Electric Drive Unit and High Voltage Battery - GM Techlink