Posted by Lyle in: Engineering, GM Q and A, Original GM-Volt Interviews, Production with 63 Comments
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Since its a new technology and drivetrain will it make the production process different and require new facilities that you don’t already have in place?
Oh yeah, we are putting different components in the vehicle but were using well understood principles. For example most of our cars what we have is what we call a ‘front cradle’. Its basically a U-shaped or hexagon shaped piece where we mount the drivetrain, where we attach control arms and things like that. We take that and we put that in from underneath the vehicle in the plant. Then we drive it with four or six very large bolts to attach it to the vehicle itself. We’ll do the same thing from a process standpoint on the Volt. Yes the bits and pieces, the drive motor will be different and so on and so forth, but the principles of how we’re putting it together will be very similar.
So it doesn’t require any retooling of your assembly plants?
Well we’ll have to retool the plant for the Volt, but the point is the processes that we use are very well understood. We know how to do those operations. The pieces that go in the cradle may be very different but the attachment of the cradle to the vehicle is going to be just like we do in all of the vehicles that we build around the world. There will be some on board subsystems that will be different, there will be some parts and pieces that will be different but we have something that we call a ‘bill of process’ or BOP. That’s the process that we use in General Motors to assemble the vehicle, and we do it in the same basic sequence for all of the vehicles that we build around the world. Because we use the same process its a process that’s very well understood. We understand the equipment thats required to do it and so-on and so-forth.
So really when you think about it, doing the vehicle itself for us, is very manageable. Its something we do each and every day around the world in large quantities.
So it really comes back to having to get the technology ready to go. That involves, we have work to do on the drive motor, I think were fairly confident of that one, because we build drive motors, transmissions, things like that so we understand the basic principles of how thats going to come.
Are you still committed to the series design or are you considering the possibility of a parallel hybrid component, for example, at certain speeds?
These are subtle variations on the same thing. I would say that the way the Volt is going to operate right now and this is exactly what we’ve said right from the very beginning, is for the first 40 miles it’s going to be a pure EV. We are not planning to turn the engine on when it’s running on its battery, that’s it. When you turn the engine on, the primary job will always be to generate electricity, that will be the primary job of the motor. And whatever we do beyond that its only something we would do if it made sense, or if we found some particular advantage in our development and so on and so forth.
So it’s conceivable that the motor could have some connection to the drivetrain at some point?
Some of us don’t even want to talk about that…there are probably some circumstances where that’s an advantage, but it’s really all about the first 40 miles, thats what we’re all focused on. And I can assure you its going to be a pure EV for the first 40 miles. Thats it. Now is it possible to do other things? Yeah I suppose so, if we figured out that there was some advantage to doing so.
I think your very well aware, Lyle, why the theory that the parallel hybrid is superior to the series is that the conversion of energy from one for to another and the efficiency loss of doing so. For example if I had a motor I put it in front of you and I tell you its a 80 kW motor, the first thing you should ask me is if thats gross or net. Because if I put 80 kW of energy into that motor I most certainly wont get 80 out of it. I will get hopefully 78 or 77. Something that would give me a motor efficiency thats very very high. So there’s always some translational losses when you turn energy from one form into another. Right. So I turn in this case in a motor, I turn electrical energy into mechanical energy and I have an energy conversion loss. And the theory has always been that the serial hybrid is not as efficient as a parallel hybrid because you have the multiple conversions of energy, You’ve got energy being converted from the form of chemical energy in the fuel into combustion the combustion energy drive the generator, the generator drives the electric motor, the electric motor turns it back into mechanical energy to drive the wheels, and you have these efficiency sorts of discussions.
Here’s the point with the Volt. For the first 40 miles its completely irrelevant, theres only one efficiency loss. And that is the gross amount of power that you put into the motor versus the net mechanical power that you get out of the motor. That’s it for the first 40 miles. Its like a nice discussion but sort of kind of silly because for the first 40 miles it doesnt apply. Job number one is to do the very best possible job we can at making the amount of on-board energy get the vehicle as far down the road as we possibly can. It’s all about range. Then after that point in time then it becomes a rather interesting story because internal combustion engines of all sorts whether they’re gas or diesel are most efficient when they run at a relatively constant speed and a relative constant load. In fact if you look at internal combustion engines you’ll find that its the transients when either load or speed or both are varying that spoils their thermodynamic efficiency from where it is. You see this efficiency argument play out in CVTs.
This entry was posted on Wednesday, January 23rd, 2008 at 6:00 am and is filed under Engineering, GM Q and A, Original GM-Volt Interviews, Production. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.
Jan 23rd, 2008 (7:03 am)Thanks Lyle,
I think that we all know now where the optimization focus is put : the pure EV 40+ miles. That is clearly the choice of GM.
Jan 23rd, 2008 (7:28 am)Lyle,
You should also focus some discussion on service issues compared to current autos. with the right design (pragmatic yet elegant) this car could easily last 30 years with parts replacements being easy compared to current designs. this is where you hit asian designs hard. it’s nice to see the asian marketing start to break.
Jan 23rd, 2008 (8:26 am)Lyle,
Great interview. I hope GM sticks with the pure series design and fully optimize it. It is a clean design, and Wrigley (#2) is right on regarding service advantage.
Jan 23rd, 2008 (8:44 am)Glad to hear GM wants to focus on the EV aspect. Finally.
Wrigley @ 2 does bring up a good point about service. The fact is, servicing this thing becomes unnecessary (except for tire rotation and possibly unforeseen battery servicing), as electric engines usually do not break because there are less moving parts. No oil changes. No antifreeze. No coolants. No nothing.
Jan 23rd, 2008 (9:08 am)Reduction in servicing applies so much more to pure EV’s; you’re really jumping the gun to assume this hybrid will require less servicing than a traditional ICE car. There is still an ICE engine with the same basic requirements as your current car (granted it should see less cycles so that should stretch the ICE maintenance schedule out). There will still be oil changes and antifreeze. The batteries even require fluid thermal management. This is something to wait and see on, not a given.
Jan 23rd, 2008 (9:14 am)I find it intriquing that Jon Lauckner takes so much time responding to …and almost “dancing around”… Lyle’s question, “So it’s conceivable that the motor could have some connection to the drivetrain at some point?” It’s almost as if he doesn’t want to deny the possibility in the interest of candor, but he also doesn’t want to admit it’s possible for fear of whacking open a hornet’s nest of other questions.
My guess, based on reading descriptions of fuel cell vehicle drive trains, is that GM may be planning to at least TEST a scheme for partially or totally diverting the range extender’s electrical output directly to the 160HP motor’s controller under certain operational scenarios. One might be a (hopefully very rare scenario) in which a major battery failure had occurred; in this case it would be wise to completely bypass the battery & power the electric drive train directly from the generator. Other scenarios might involve driving conditions such as extremely heavy loads for long periods, like driving up Pike’s Peak, or simply the case of a long non-stop trip when, after the battery is at its EOC, the car’s range might be extended somewhat by eliminating battery losses (however small).
However, I think it’s less likely GM would MECHANICALLY divert the ICE’s shaft output through some king of transmission or gear train directly to the drive wheels, because the generator & motor efficiencies are too high to justify that added cost/complexity. It’ll be interesting to see what they decide.
Jan 23rd, 2008 (10:05 am)Mr. Lauchner speaks much about energy conversion efficiency, but he needs to shift his focus to energy SOURCE substitution FROM carbon TO renewable electricity and OVERALL vehicle efficiency.
Also although Parallel design MAY be more efficient at energy conversion, this is just ONE component of overall efficiency. The parallel design becomes far LESS efficient at overall energy efficiency as compared to serial design when the cost/energy of production, mass/inertia energy over lifespan, complexity/maintenance and vehicle lifespan/replacement costs are factored in.
It’s NOT just how much energy is consumed per mile of operation, but is that energy renewable and how much was consumed from initial production through to end of life recycling.
Complexity and Mass are the plug-in parallel’s key design flaws.
GM must choose ONE type of system because if they use a HYBRID of both to drive the wheels, the energy efficiency is lost among the other factors.
Of course, efficiency becomes less important when the energy supply is abundant and or unlimited.
Examples include:
Solar – thermal, PV, wind and wave conversion
Zero point – gravitational energy manifested in water flow and lunar tide conversion. Future “possible” ZPE sources may include Cold Fusion, electromagnetism or water dissociation through solar thermal + frequency as H2 is simply an electron battery.
Man never knows what he will discover around the next corner however I believe that the future IS electricity. Apparently, so does GM.
Jan 23rd, 2008 (10:28 am)I wasn’t sure what to make of what Lauchner said, because he seems to contradict himself.
He talks about efficiency in power conversion of the Parallel Hybrid, but then he makes reference to thermal efficiency of an ICE operating over a narrow range, which is exactly how the 3cyl will operate in ERev.
I for one was unaware GM was even considering connecting the 3 banger to the wheels, that surprised me. Sure hope they stick to the original design.
Jan 23rd, 2008 (10:46 am)Optimizing the car for the first 40-miles makes a lot of sense, for the people whose lifestyle is being targeted by the Volt!
Within this context, I’d like to hear more about the range-extenders that they’re considering? I’m also curious if the design team is considering the possibility of swapping future versions of the range-extender (with different fuel possibilities) as an aftermarket option?
Jan 23rd, 2008 (11:35 am)Dan Neil’s “Highway 1″ piece in yesterday’s LA Times was a report on the Detroit auto show titled “Start your engine, but plug in first”.
Subtitle: Road ready or not, electric cars and hybrids turned the most heads at the annual event. Standard models could barely muster a yawn.”
Even so, $40,000 does not work for me.
Jan 23rd, 2008 (11:36 am)I want to know if regenerative braking will extend the range over 40 miles.
Jan 23rd, 2008 (11:54 am)Wow said ” you’re really jumping the gun to assume this hybrid will require less servicing than a traditional ICE car.”
The only reason I would want to buy the car, is reducing the cost of total ownership. I don’t care much who gets the money, what I care about is that there is less of it leaving my pocket.
I would buy a Volt if I am reasonably sure that over 10 years and 150,000 miles, it will probably cost less than a car I can buy for 20k that got 30 to 35 mpg, and was made by Honda or Toyota. To do that, GM has to produce a car that allows me to buy electrons instead of gasoline to run it at least part time, and reduce the maintenance cost below their competition.
If the Volt offers no improvement in vehicle life cost of ownership, GM has lost again.
Jan 23rd, 2008 (11:57 am)Mr. Lauckner does a reasonable job explaining the parallel/serial trade-off. It’s a matter of whether the efficiency gain from regulating the generator load and eliminating the mechanical transmission is greater than the efficiency loss from the generator, charger, battery, motor controller, and motor.
But while Lauckner is correct to imply that this equation could be very close (depending on the scenario), I can’t see how GM, from a design standpoint, could be contemplating the possibility of a mechanical linkage at this stage in the game. It’s either been considered as a possibility from the beginning or it’s completely off the table.
I’m also skeptical that there would be a direct electrical connection between the generator and motor controller, bypassing the charger and battery. My understanding is that the motor controller uses pulse modulation. There would at least need to be a large capacitor to decouple the generator load from the pulse draw, and the battery fulfills this requirement with just a little bit of additional electrochemical overhead.
So either GM has been considering a mechanical transmission and/or a capacitive coupling from the beginning or it’s already out of the question. Either way, this is the kind of thing where GM has a strategic interest in not taking options off the table in public.
Jan 23rd, 2008 (12:06 pm)When we talk about Plugins, the only parallel design that is applicable is of the Prius. Honda IMA type is ruled out for plugins as ICE always runs along with Motor though ICE is not generating power and also has transmission. Thats the reason Honda IMA type is less efficient in City driving than prius.
Prius Vs VOlt:
————-
1) Prius Motor Powers the wheels directly without having ICE to spin. Same is with the Volt.
2) Prius ICE can also directly power the wheels by allowing some of the ICE power to get converted to electricity and then to
Motor->wheels. So still Prius has efficiency issues with ICE->Generator->Motor->Wheels. But only some of the power of ICE is used like this, the remaining power is used directly to power the wheels. But in Volt the entire energy of the ICE is converted to electricity which is less efficient. So Prius clearly has advantage.
3) Prius ICE rpm Varies a lot. Volt ICE doesn’t. So Volt has efficiency advantage.
Clearly both have advantages and disadvantages. But I think if design of the Prius is optimized for plugins that could travel 40 miles on battery, Clearly Prius will be more efficient than Volt.
Jan 23rd, 2008 (12:06 pm)i got a idea why dont they take out all the specialized bs from the volt like the fancy roof and put in a regular one to cut costs. that roof prob cost like 3 grand anyways. gm should be doing everything possible to make a base model affordable for everyone. if people want some lame glass roof they can pay extra for it. whats important is availability to the average consumer.
Jan 23rd, 2008 (12:23 pm)This is one of the most interesting interviews yet. Finally we see some of the GMs internal thinking when it comes to Serial vs Parallel. I’m glad to see that they have really thought this one through. Serial makes the most sense if it’s all about electric range. For the Plug in Prius (assuming a shorter all electric range) then parallel makes the most sense. No right or wrong, only a question of circumstance.
Jan 23rd, 2008 (12:49 pm)I think the primary goal of everyone interested in the volt is to drive it as an EV as much as possible. People like me who drive 60 miles a day unfortunetly will need some fuel. (Unless I can make it up coasting down hills)
I really don’t want an ICE connected to the wheels. Efficient or not. Trains have been running likes this for decades and now its our turn.
Jan 23rd, 2008 (1:08 pm)Just reiterating Luke’s question about the design implications of switching out the gasoline ICE for other fuels. I’d asked some time ago about the series design seeming to make the car a bit more modular, as I’d really love to have the option to run the generator on biodiesel instead of gasoline (and others would like ethanol, for instance, depending on their local circumstances)… So, by design, can they make it easier to do that switch?
Jan 23rd, 2008 (1:11 pm)There was an interesting study put out a few years ago by AC Propulsion on a range-extender “trailer” they towed behind their tZERO ev. It showed a fuel->battery conversion of 22%, and a fuel efficiency of ~32mpg.
However, I feel that study was seriously misleading for a couple of reasons:
1) They used an Otto cycle motorcycle engine tuned for high specific power, not high efficiency. If they had used a Miller or Atkinson cycle engine (like that used in the GM Two-mode hybrids or Ford/Toyota systems) they would probably have seen much better results. Those engines can achieve up to 37% thermodynamic efficiency at their peak (according to Argonne national lab), versus 25% for the regular otto cycle.
2)If they had absolutely insisted on a regular otto, they could also have gotten better efficiency simply by running a larger displacement engine at ~3000rpm rather than max out a smaller engine to get the necessary horsepower to run the generator. But they seemed to place weight and space efficiency as their priority.
3) They had their range extender on a trailer that added its own significant amounts of drag and rolling resistance.
Anyone else wanna chime in on this? Nasaman, et al?
Jan 23rd, 2008 (1:16 pm)GM needs to put one of these in Silicon Valley to shed the horrible image that the local dealers project and usher in the age of electric cars.
http://www.nytimes.com/slideshow/2008/01/22/arts/20080123_BMW_Slideshow_index.html
Jan 23rd, 2008 (1:19 pm)MC- I doubt they could make the engine run on both diesel AND gasoline. The two engine types run based on completely different principles. A novel engine design like the Cyclone could probably handle it rather easily though.
As far as ethanol goes, I think it’s more a question of making sure that the engine can withstand corrosion from the EtOH.
Jan 23rd, 2008 (1:53 pm)I think that Mr Lauckner, was being open and having an intelligent conversation about the pros and cons of different designs, and explaining GMs goals (40 miles on electrons only).
I would not read anything into what he said as implying any potential changes in direction for GM, or in anyway implying that GM had a sub optimal design. Explaining a design decision usually involves examination of the alternatives.
Jan 23rd, 2008 (2:24 pm)Regenerative braking recovers less than 10% of the energy used to accelerate the vehicle. So if a car could go 26 miles without regenerative braking, it might be able to go 28 or so miles with regenerative braking.
Jan 23rd, 2008 (2:37 pm)Thanks, AES, I was thinking of the implications of switching out the gasoline ICE altogether for one configured to handle diesel (or ethanol). Although a truly flex-fuel ICE would be interesting, that’s beyond what I’m curious about at present.
People have regional preferences for their fuel of choice, and I’m just wondering if GM can include easily replacing the ICE for a particular fuel in their design (which I guess they are since they mentioned diesel on the European version, right?). I certainly don’t want to have to buy a new Volt just to get another fuel, and with the series design it seems much more manageable than the complete switch that has to occur with traditional cars…
Jan 23rd, 2008 (3:15 pm)The Cyclone is attractive from an ultimate flex-fuel perspective, since it handles everything by external combustion, rather than internal:
http://www.greencarcongress.com/2007/11/cyclone-power-t.html
Optimizing an engine exclusively for ethanol would be interesting for people in Scandinavia where GM’s Saab “biopower” initiative seems to have a lot of governmental support.
Jan 23rd, 2008 (3:51 pm)I agree with AES on this one.
The Heat Regenerative Cyclone Engine merits closer attention. This design answers the problems of size, complexity, and high pressure gasses that have kept the Stirling engine from becoming practical because it recycles 30% of the heat that is wasted in Internal Combustion without the need of a radiator, transmission, catalytic converter, or complex electronic ignition controls.
It’s highest torque is at 1 rpm and a 100 HP Cyclone engine would weight about 320 pounds, and is much cheaper to built than the 400-lb ICE equivalent.
The exhaust is much like standing in front of a shop space heater. Unlike internal combustion, external combustion when it takes place in a centrifugal chamber burns MUCH more of the available hydrocarbons so little or no pollution controls are required.
http://www.cyclonepower.com/index.html
http://peswiki.com/index.php/Directory:Cyclone_Technologies_LLLP
Jan 23rd, 2008 (4:22 pm)I am an engineer and the greatest losses are from the Internal Combustion engine.
Electric motors are very efficient now.
GM need to look at some technologies forgotton like turbines that re-coupe heat etc to link to the generators.
http://64.233.169.104/search?q=cache:0fcYiubl9wkJ:en.wikipedia.org/wiki/Gas_turbine+high+efficiency+gas+turbine&hl=en&ct=clnk&cd=1&gl=us
Mico turbines some are greater than 60%.
I would work with GE and get a contract to make a Turbine-Generator charger.
Some turbine engines in aircraft for example. The heat can be feed back into the intake for greater burn and better emmisions. An aircraft cannot use this technology because it needs lift but connected to a generator etc can.
Transmission losses at high rpm are great but generators can be tuned to great efficienty less than 10% losses.
So people are forgetting the mech tranmission losses and running an engine at various RPMS. The great tunning ability of turbines and other engine technologies come into play by running your engine at one speed constant to get the most efficient transfer of energy.
So from my understanding the Series hybrid has has Toyotas beat hands down if they start to look ouside of piston engines.
I. E. fuel cells, turbines etc.
G
Jan 23rd, 2008 (4:28 pm)http://en.wikipedia.org/wiki/Image:GE_H_series_Gas_Turbine.jpg
The H series is 90% if the exaust gas is used for Heat and AC systems in the car.
Jan 23rd, 2008 (5:03 pm)SLNTAX, #15:
Amen!
“Simplicate and add lightness.”
“What ain’t there don’t give you no trouble.”
Jan 23rd, 2008 (5:07 pm)His argument that series can be more efficient than parallel is right on the money. It’s very significant that a combustion engine can be dramatically optimized if it has a narrow operating range. Using the Volt system that always drives electrically and occasionally uses gasoline to generate electricity will allow GM to optimize the engine – perhaps using an adkins cycle engine like that on the Ford Escape, but taken to an extreme of efficiency such as would be found on a train locomotive. In fact, that’s what they are building – a train locomotive that has 40 miles worth of batteries. And the batteries become very significant to the optimization of this engine, because they allow for the engine to operate at as near a perfect level as can be achieved – even if that level is dramatically under the peak energy need of the vehicle. With the Volt it doesn’t matter because it will have some small amount of power still available in the battery. The Volt might only need a 2 cylinder, 40 HP engine because the engine is a tortoise and the battery allows the car to be a hare. All they need to do is to figure a good starting point of what they consider to be average needed power and allow for the engine to produce a small amount more than that as a margin of error. They could even program the car to “learn” how much power an individual driver will use based on driving style. The Volt just got smarter.
Jan 23rd, 2008 (5:10 pm)#27 – The problem with gas turbines is complexity/tight tolerances and exotic/expensive materials required to handle the high temperatures and dynamic loads at the blade tips. This makes turbines with recuperators efficient because they can reuse heat, but also VERY expensive.
Heat Regenerative Cyclone Engines ALSO reuse heat like a gas turbine, but they are lubricated and cooled by the same super heated, high pressure water that transmits power from combustion to the pistons and is then recycled back to be reheated & reused.
As an engineer, what is the factor of available energy in high pressure superheated liquids vs low pressure superheated dry gasses?
Advantage – Heat Regenerative Cyclone Engines
Jan 23rd, 2008 (5:16 pm)Talks Says:
2) Prius ICE can also directly power the wheels by allowing some of the ICE power to get converted to electricity and then to
Motor->wheels. So still Prius has efficiency issues with ICE->Generator->Motor->Wheels. But only some of the power of ICE is used like this, the remaining power is used directly to power the wheels. But in Volt the entire energy of the ICE is converted to electricity which is less efficient. So Prius clearly has advantage.
Wise reply:
I respectfully disagree. Generating a constant power with a highly optimized ICE is far more efficient than any gain that the Prius could achieve by converting the mechanical energy of a far less efficient ICE directly into locomotion. Unless the locomotion desired was highly constant (say a perfect 70 mph,) and never changed more than a couple MPH. This obviously would hardly ever be the case.
Jan 23rd, 2008 (5:20 pm)Trains != cars. Speeds vary more with cars. Trains are almost always cruising at a standard speed.
It will be hard for the range extender to run at a constant speed unless that speed is set for the highest possible energy drain when the batteries are dead. The ideal is that the ICE would not charge the batteries any more than is required to get home and plug back in. But the reality is if the ICE kicks in and keeps running as you stop/start that you will probably have surplus charge when you park it.
Jan 23rd, 2008 (5:21 pm)AES Says:
January 23rd, 2008 at 1:19 pm
MC- I doubt they could make the engine run on both diesel AND gasoline. The two engine types run based on completely different principles. A novel engine design like the Cyclone could probably handle it rather easily though.
Wise Reply:
GM has already developed just such an engine that can use either Gasoline or Diesel. It is very efficient and I hope they build it. It uses extraordinary compression to cause gasoline to ignite as diesel would and I assume it regulates the compression based on the fuel being used.
Jan 23rd, 2008 (5:24 pm)The Volt needs an engine that can responsively produce widely varying amounts of power.
When idle, it needs to produce very little power, and when the accelerator is floored, it needs to produce max power. And the time difference between these two states might be a fraction of a second.
Produce too much power at idle and you’ll charge the battery too rapidly. Produce too little power under heavy acceleration and you’ll quickly drain the remainder of the battery and the car will become unacceptably slow.
Basically, the Volt engine will have to have the characteristics of a regular car’s engine. Turbines and Stirling engines have been tried in regular cars and they are simply much less suitable than regular piston engines. Seems like a complete non-issue for me.
As for diesel, switching the gas ICE for a diesel in the Volt should be just as easy for the manufacturer as in a regular car. Remember, the Volt is more or less a regular car, just with a smaller engine, a big motor, and a battery. So, just as there are car models with gas, diesel, flex-fuel, turbo/superchargers, etc., it will likely be the same with the Volt.
Also, one thing that didn’t ring quite true with this interview (and others) is how much emphasis is being placed on the 40 mile range. How hard can this possibly be? The EV1 got 120+ miles per charge. The Tesla supposedly gets 200+. These vehicles are more or less identical to the Volt in weight. The Volt’s battery will proportionally be bigger so I don’t see what’s so freakin’ hard about this. And why is 40 so absolutely critical? The competition is HYPOTHETICALLY a plug-in Prius with 7 mile range. If the Volt only goes 4 or 5 times as far, would it really be a tragedy?
Jan 23rd, 2008 (5:55 pm)“It will be hard for the range extender to run at a constant speed unless that speed is set for the highest possible energy drain when the batteries are dead. The ideal is that the ICE would not charge the batteries any more than is required to get home and plug back in. But the reality is if the ICE kicks in and keeps running as you stop/start that you will probably have surplus charge when you park it.”
Correction: the batteries will never actually be “dead” – the range-extended mode will sustain the batteries at 30% state of charge, so the ICE should ideally handle AVERAGE power with the accumulating surplus charge in the battery handling power spikes.
Jan 23rd, 2008 (6:09 pm)The generator will come on at 30% SOC and shut down at 70% SOC. It will run at constant speed for maximum efficiency. This will maximize battery life and leave a cushion so that we can override the generator cycle on those occasions when we are at 30% SOC with say 2 miles to next charging opportunity or when we are fully charged at 70% SOC and need a little battery room to capture braking energy.
Jan 23rd, 2008 (7:27 pm)Interesting discussion.
If I need to drive, say, 60 miles, I would like to be able to tell it to charge just enough so that it got me to my destination (where I could plug in again) at 30% charge rather than closer to 70%. It would be difficult to program it to do this even with GPS and a destination entered into a nav system, but it would be nice if it could.
Will there be a way of manually starting or stopping the generation within that 30% to 70% range? I can see this being useful for some commuters who were outside the 40 mile range and wanted to minimize gasoline consumption.
Jan 23rd, 2008 (9:03 pm)MikeFromEastCoast, The Volvo Re-Charge is like that. They are saying the driver can run the on-board gen-set while on the open highway and then turn it off for City driving, thus controlling the charge times.
Jan 23rd, 2008 (10:10 pm)“If I need to drive, say, 60 miles, I would like to be able to tell it to charge just enough so that it got me to my destination (where I could plug in again) at 30% charge rather than closer to 70%.”
Mike – 38, from what I’ve read, the Volt will drive in EV mode until the SOC drains from 80% down to about 30%. That’s when the ice kicks in, but only to keep it at “around” 30% SOC, or a little over. So if your ice driving doesn’t require much juice, it will throttle way back to stay near 30% SOC.
If it kept a constant rpm, the ice would eventually be over charging, as supply exceeds demand.
Jan 24th, 2008 (1:02 am)Looks like an important news.
Continental AG struck a deal with Maxwell technologies to buy Ultracapacitors for creating an electrical stabilization system for
a new automobile model year 2010. Also mentioned about Major automaker.
I suspect this is for VOLT.
link:
http://money.cnn.com/news/newsfeeds/articles/apwire/4cb3ed9b4369f94634a540d88e0e1874.htm
Jan 24th, 2008 (1:33 am)Talks,
Very interesting indeed. If it’s what we think it is then Conti has some pretty ambitious plans for their pack. There were even suggestions on this site for using ultra caps.
Jan 24th, 2008 (1:39 am)BTW, just though I’d mention that Wikipedia lists Maxwell as a major competitor of EEstor.
Jan 24th, 2008 (2:08 am)This ultracap news is nothing new. The Prius already uses two ultracaps. If the Volt didn’t use any, I’d be astounded.
Jan 24th, 2008 (3:36 am)Things to consider:
1. This talk of serial vs par. is rediculous. Serial is much much better. You will never see a transition from serial to parallel. Any gained efficiency of a parallel is quickly lost when you have to stop at a stop light and wait for it to turn green, etc etc. This subject should never even come up as it is absurd.
2. Talk of working on fuel efficiency of the ICE engine is going to probably go the way of the dinosaur. Over time the need for the generator will decrease. Battery technology is not likely to stop or regress. Evolution of the car is towards elimination of the ice component. Only question there is how long will that take. Eight years, twenty years, forty years??? But however long it does take remember their will be a trend in that direction from day one.
Jan 24th, 2008 (3:38 am)3. Maintenance cost will be less on a seriel hybrid. This is going to be one of the strongest selling points of it over a par. hybrid once people discover this.
Jan 24th, 2008 (5:49 am)The number of errors posted here is truly amazing.
It’s very clear that some have absolutely no idea what the difference is between a “parallel” and a “series” hybrid, because Prius is neither. Having 2 motors and a power-split-device gives it characteristics of both types.
A “parallel” hybrid only has a single motor and it is bonded directly to the engine, lacking the ability for electric-only drive. Prius can drive up to 62 MPH with the engine stopped, so obviously it is not “parallel”. Prius can’t go backward using the engine at any speed; reverse propulsion is always electric-only like a “series” hybrid.
As for efficiency differences, those having studied history are well aware of the fact that real-world implementation doesn’t always match on-paper comparisons. Don’t believe claims without actual data to support them.
Jan 24th, 2008 (6:20 am)#43Grizzly:
I like Wikipedia but in this case it’s wrong. If EESTOR pulls off what they claim they will, their eesu (electrical energy storage unit) will have no competition.
Imagine having a capacitor with the energy storage ability of a battery at a fraction of the weight and cost. And scalable. All electric cars, here we come. Not to mention fast charge stations. Goodbye liquid fuel.
Jan 24th, 2008 (7:49 am)#47, john1701a:
I can disconnect my car’s engine from the driveline by putting it in neutral. Does that mean I don’t drive a gas powered car?
The fact that the Prius can combine mechanical power from its engine and motor means its a parallel hybrid. The fact that one or the other isn’t always engaged is irrelevant.
Jan 24th, 2008 (9:26 am)>> The fact that one or the other isn’t always engaged is irrelevant.
You can’t just simply lump together 2 entirely different kinds of hybrid.
Choosing to call a “full” hybrid parallel means you must identify the “assist” hybrid by some other term for the discussion to remain constructive.
Jan 24th, 2008 (11:36 am)John Enterprise
A parallel hybrid is a big step over gas only cars, as you are substituting gas with electricity, sometimes.
The problem is that the ice always has to be in “standby” mode, as it could be needed to provide full power at any time. In order to keep it’s SULEV pollution status (a cold engine is the worst polluter), the Prius engine starts up 7 seconds after the car is turned on as needs to warm itself up. And as you drive around, the engine will come on and off even if you don’t need it.
48 mpg is great, and double that is even greater. But, I don’t want to use ANY GAS AT ALL! And that’s what a serial hybrid, like the Volt, will do for me, and tens of thousands of others. And don’t forget that for most drivers we’re not talking low emissions, we’re talking no emissions!
Jan 24th, 2008 (12:14 pm)john1701a Says:
January 24th, 2008 at 5:49 am
Prius can drive up to 62 MPH with the engine stopped, so obviously it is not “parallel”.
Wise:
No, I don’t think it can. Maybe under some sort of downhill coasting situation like coming out of the mountains in WVA, but under normal circumstance the ICE will kick in at 30-35 MPH on a Prius.
Jan 24th, 2008 (12:18 pm)>> I don’t want to use ANY GAS AT ALL!
Then a “serial” hybrid isn’t what you want either. At times, it too will run the engine.
And again, the understanding of how Prius works is not entirely known to some. For example, that comment about engine startup doesn’t address the plug-in upgrade or the “EV” button.
Also, emissions from electricity are clearly being forgotten. Coal is far from pollution free.
Jan 24th, 2008 (12:55 pm)A lot of people will buy Volts with the intention of using it as a strict EV and will just disable the ICE if it comes on inappropriately.
Jan 24th, 2008 (1:35 pm)Here’s a simple idea for GM to improve efficiency of the Chevy Volt. Have every Volt come equipped with a GPS standard. You set your destination, even approximate destination.
From there, the Volt gets an estimate of miles to be travelled. It can know if it will be traveling farther than it’s 40 mile round trip range. Then it could plot the most efficient time to run the batteries.
Furthermore, GM should study whether the efficiency of running the generator is more or less when going up or down hill. If the test show any advantage either way, then GM’s GPS system should also included embedded topographical data. Then run the generator accordingly.
This would provide something far superior than Toyota’s Prius offers. Not just a hybrid or REEVer that is optimized mechanically for efficiency. But also a vehicle that is equipped with artificial intelligence to optimize it’s own operations for maximum efficiency.
(Kudos to MikeFromEastCoast for having a similar idea as mine, even if he has less faith in the idea)
- The Saj
Jan 24th, 2008 (2:27 pm)Interesting that both Lyle and the GM guy refer to the Volt’s design as a series hybrid, and not GM’s marketing term “range extended EV”. Seemed just like yesterday folks were insistent that the Volt is not a series hybrid. Glad to have folks wake up and separate marketing from the technical.
I do assume GM will make the ICE support pure gasoline (E10 here in the Northeast) all the way up to E85, as from my understanding it only cost auto makers less than $200/vehicle today to support it. Though I also believe ethanol, at least corn based, is just a boondoggle (tax credits/subsidies) for the mid-West, using almost just as much fossil fuels to produce, never mind how it’s affecting food prices.
Some folks have mentioned turbines… which is interesting as GM’s 1st prototype series hybrid EV had one! See http://www.evworld.com/archives/testdrives/gmshev.html … yes, that’s 10 years ago (a range extended 4 passenger EV1). At least one benefit of a turbine is not only being a flex fuel, but it’s proven technology. Though as others also mention, materials needed may make it cost prohibited.
Regarding the Cyclone engine… this is new to me… however, one has to wonder if this is the next best thing since sliced bread, why their stock price has gone from a 52 week high of $20, down to being a penny stock (12 cents) today? See their own investors page at http://www.cyclonepower.com/investors_info.html
Jan 24th, 2008 (3:36 pm)John Enterprise #52
“And again, the understanding of how Prius works is not entirely known to some. For example, that comment about engine startup doesn’t address the plug-in upgrade or the “EV” button.”
Not sure who you are referring to. I installed the EV button 2 years ago, and have also driven a PHEV Prius (yes, it was very cool!).
The issues still remain. If you drive normally, from the high to the low SOC of the battery, you will burn gas with the parallel hybrid, but NOT with the serial.
Jan 24th, 2008 (4:15 pm)#50, john1701a:
>>You can’t just simply lump together 2
>>entirely different kinds of hybrid.
I’m not even sure you understand what the words “parallel” and “serial” even mean. Draw a block diagram of a Prius. The box for the engine and the box for the motor are both mechanically connected to the transmission (or torque combiner, or whatever you want to call it) in a PARALLEL fashion. Now draw a diagram of a Volt. The engine is connected to the battery is connected to the motor, all in a straight line, in a SERIAL fashion.
You’re trying to draw some kind of fine implementation distinction between Toyota hybrids and Honda hybrids, but they really might as well just be the same when compared to the Volt. It’s like talking about a gas engine with variable valve timing vs. one without… yes, they’re different, but they’re both gas engines.
Jan 24th, 2008 (4:59 pm)For what it’s worth, Sherry Boschert, in her book “Plug-in Hybrids” (subtitle “The cars that will recharge America”) does list as examples a Honda Insight as a parallel hybrid, and the Prius as a series-parallel hybrid, saying the Prius “combines the two designs, allowing the gasoline engine to drive the wheels or be disconnected temporarily so that only the electric motor drives the wheels”.
Regardless, as has already been mentioned, a parallel hybrid is a lot more complexity on an already complex internal combustion engine. And a series-parallel hybrid is even more complex than that…
and the more complex something is, the more likely it is to fail, thus needing more maint. and repairs. Something great for the dealership and the auto maker as the sale of the vehicle itself is only a small part of the revenue they make (especially so for the dealership).
A pure EV is definitely the least complex, with the overall fewest moving parts (70-90% depending on who you talk to, compared to a conventional vehicle with an internal combustion engine). A series hybrid EV adds the complexity of the generator and what drives it, but still far less complex than any parallel (plain or combo w/series) design.
As has also been mentioned, keeping it a series non-parallel design, allows for the easy swap by the auto maker of the generator, be it an internal combustion engine (gasoline/ethanol, or diesel/biodiesel), turbine, or fuel cell (hydrogen or other fuel) [even though hydrogen economy is a myth].
It’s still going to be interesting to see how the whole business model is going to work if dealerships and auto makers are making less post-sales revenue (parts/service) on each vehicle. It could be why GM is backing off on MSRP’ing it for under $30k, realizing they need to take more profit up front for both themselves and the dealerships. It’s also going to take a while for consumers to catch on that their total cost of ownership over the life of the car is what’s important, not just the initial price… though lots of consumers just don’t have the ability to afford paying for it upfront.
Jan 24th, 2008 (8:40 pm)A hybrid with only 1 motor which must operate at the same RPM as the engine has almost nothing in common with a hybrid that has 2 motors and an engine that all operate independently.
Volt will be considered the third type available. Like it or not, that’s the way it is.
Jan 24th, 2008 (11:57 pm)#60 (john1701a), what are you talking about?
Prius – a series-parallel combo hybrid
Volt – a seris hybrid
ike it or not, that’s the way it is, and that’s the final word
Jan 25th, 2008 (9:10 am)That’s what I said, back in September…
http://www.gm-volt.com/2007/09/22/gm-determined-to-be-automotive-technology-leader/#comment-8418
…but many are still misusing the “parallel” term, contributing to the confusion.
Jan 25th, 2008 (10:58 am)Why do you people keep talking about idling ICE? If power isn’t needed to charge the battery it will be off.
Guys, this is a battery driven car. It happens to be carrying an ICE powered battery charger that will be started to charge the batteries.
Please stop making it complicated.