2012 Buick LaCrosse with e-Assist Technology

    2012 Buick LaCrosse with eAssist Technology. (GM)

    by: Rex Roy | AOL Autos

    This year's recently concluded L.A. Auto Show was all about green, from the Kia Optima Hybrid to the Toyota Rav4 EV to GM’s 2012 Buick LaCrosse with eAssist. What’s that last one, you ask? How is this Buick a green machine?

    Well, next year’s LaCrosse will be fitted with GM’s newest hybrid system, but the company is being coy about the technology, so much so that they’re not even calling it a hybrid.

    "eAssist is similar in principle to the belt-alternator-starter (BAS) first used on the 2007 Saturn Vue Green Line," explained Steve Poulos, eAssist global chief engineer.

    If At First You Don’t Succeed

    For those who don't remember the Saturn Vue Green Line Hybrid, it ranks as one of the least successful forays into the hybrid market. GM didn’t sell many of these mild hybrids, and a painful recall harmed the reputation of the system.

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    But now GM is back with a new and improved version. A belt-alternator-starter system combines the function the alternator and starter motor into one multi-talented device, which hangs off the engine looking somewhat like an enormous alternator. (An alternator is the underhood component responsible for recharging a vehicle's battery and supplying electricity to the vehicle whenever it's running.) The BAS is connected to the crankshaft of the engine by a substantial drive belt, kind of like a conventional accessory belt on steroids.

    In the eAssist system, this combined alternator/starter is an AC induction motor that is capable of multiple functions. It can generate electricity just like an alternator -- or for recharging the Buick's Hitachi 65-pound lithium ion battery array. It can also be used to start the engine. And unlike in the previous generation, it can actually propel the vehicle by itself in certain limited conditions.

    New Application For Buick

    In the 2012 Buick LaCrosse, the BAS is attached to 2.4-liter four-cylinder engine and six-speed automatic transmission. The engine and transmission are designed to enable regenerative braking and battery charging during coasting or while braking.

    GM says that the BAS system adds 15 horsepower and 79 lb-ft of torque, which increases the fuel economy by 25-percent. So the 2012 LaCrosse with eAssist should be rated at 25 mpg city and 37 mpg highway -- solid numbers for well-equipped, comfortable mid-size sedan.

    eAssist enhances mileage by "assisting" the gasoline engine with its work, and by making start/stop functionality possible. This is important because when the engine shuts off it stops consuming fuel entirely, for instance, while waiting at a red light. The eAssist system can then supply electricity to the vehicle accessories for up to two minutes. When the engine is cued to automatically re-start, the BAS delivers torque through its belt directly to the engine's crankshaft. This spins the engine back up to operating speed before the ignition fires to make the re-start smoother. The BAS then supplies torque assist as needed when the driver accelerates.

    The eAssist's battery pack is tiny compared to other hybrids, just 0.5 kWh compared to a Prius's 1.3-kWh NiMH pack or the Chevrolet Volt's massive 16-kWh array.

    "Hybrid batteries provide power for longer durations. Our system is designed to charge and discharge in bursts so we don't need more capacity," explained GM's Polous.

    Not A Hybrid? Really?

    None of GM’s auto show literature described eAssist as a mild-hybrid or a hybrid system of any sort. It’s curious that the percentage bump in fuel efficiency for the LaCrosse with eAssist is just a tad below the improvement in GM’s full hybrid system used in the Chevy Tahoe and Cadillac Escalade. In other words, eAssist is delivering an economy boost nearly equal to GM's much more sophisticated and complicated dual-mode hybrid system.

    As for how it compares to other contemporary fuel-saving technologies, eAssist is less complex than a full hybrid such as the Toyota Prius or Ford Fusion. These vehicles have large batteries and powerful electric motors that can propel these vehicles for miles on nothing but electrons. Their fuel economy gains are much greater -- a 50 percent improvement, in the case of the Ford Fusion Hybrid.

    However, eAssist is more complex than the start/stop technology used in the 2011 Porsche Panamera and Cayenne or the Mazda iStop (currently for sale in Japan and across Europe). Neither the German or Japanese options allow for any electric assist to the gasoline engine. These systems save fuel strictly by allowing the engine to shut down while the vehicle is idle in normal traffic.

    eAssist more closely resembles the functionality offered by the Honda Insight hybrid and BMW’s ActiveHybrid 7. These hybrids use modestly sized electric motors located between the engine and transmission. Like eAssist, these electric motors do provide assist as well as start/stop, so they save fuel in two ways.

    A Modular Design

    We asked Poulos why GM dusted off its old BAS technology instead of going the same way as Honda and BMW. "We were already familiar with BAS and had learned so much about a simple, cost-effective system that added economy," he said. “There are challenges with adding an integrated motor into transmissions. Particularly in a front-wheel-drive application, packaging becomes an issue because it (the electric motor) adds length.”

    So GM didn't want to invent something new when they already had something in house that worked and could be made better. Another benefit is that GM's BAS is also modular, meaning that it could be used on other vehicles and even other powertrains, such as smaller four-cylinder engines or larger V6 engines. The new BAS operates at three times the voltage of the old system and produces more than three times the power (11kW compared to less than 3kW).

    Standard Equipment

    When the 2012 LaCrosse goes on sale in the late spring of 2011, Buick will offer customers two engine choices for an identical MRSP: An eAssist 2.4-liter four-cylinder or a 3.6-liter V6. The 3.6-liter V-6 engine option cost $1,370 on the 2011 LaCrosse, so expect a base price starting around $28,000 for an eAssist LaCrosse.

    But regardless which engine you select, hybrid badges won't be included. GM says one of the lessons it learned earlier this decade is that when customers see a hybrid badge, they assume the vehicle should deliver Toyota Prius mileage (think 50 mpg). The Green Line vehicles that Saturn offered, as well as the Chevrolet Malibu Hybrid (2008-09) were widely avoided because they didn't deliver the mileage the public expected from a hybrid.

    So it seems that GM is avoiding the issue by not calling the eAssist what it is, a mild-hybrid. Regardless, the technology promises significant fuel economy gains for a modest price increase. As for how the system actually works on the road, we'll let you know once we drive one.

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    1 - 20 of 107 Comments
    JamesKos1 Feb 04, 2011 3:59 PM
    Hey bruce. The g.m. company is paying back there loans plus interest. where have you been wake up and smell the roses.
    Report This
    GaTripathi Dec 15, 2010 10:10 PM
    Report This
    tjstieg Dec 13, 2010 5:00 PM
    GOVERNMENT MOTORS will make you be green whether you want to or not.
    Report This
    greenannali90 Dec 12, 2010 8:59 PM
    Do you want to experience i-nterracial da-ting? --- B l a c k W h i t e C u p i d . C 0 M ----- It gives you a chance to make your life better and open opportunities for you to meet the attractive interracial singles and treat you like a Queen. Maybe you wanna check it out or tell your friends.
    Report This
    carahsinsights Dec 11, 2010 5:09 PM
    unclogum - i agree with you on both comments, and corrolla's stay on the road forever, that CAN NOT be said for any buick in history.
    Report This
    insightinsound Dec 11, 2010 3:09 PM
    avalosdebra ---- you're a man after my own heart. I have spent 50 years of my life working with aftermarket/performance-improvement (both power and efficiency) parts, as well as manufacturing my own for my usage when what I wanted was not available. There is a huge market for what you are proposing and I agree it could become more "universal", and less performance-specific, to the benefit of many vehicle owners. The concept is certainly in place and has been since the late 40's... it just needs to be expanded. Good Call - Good Thought. I've been encoraged by some of my associates to market some of my improvements. Perhaps you can develop some improvements yourself and/or encourage others to do so. That's the American way..........
    Report This
    avalosdebra Dec 11, 2010 2:36 PM
    the cost of today cars are also higher than some homes today. and what i was trying to say is not make new cars every year just make new parts for the ones we have allready. just like you would if you were customizeing your car/truck or what ever ride you have that would of been better to make new parts that just fit in where the parts that are in now. i think that would of been better. also they could make these car a lot more lighter and stonger with the materials they have today
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    insightinsound Dec 11, 2010 2:22 PM
    avalosdebra ----- your point is well taken. To put some perspective on the subject though... consider the first modern "flat-screen" TV's... They cost as much as the Buick when they came out. Now, with even better technology applied, the y often are less than $1000... even $399 for a smaller one. Technology has always evolved that way. Ford introduce autos that everyone could afford, however, his product was based on evolving application of automotive technology that only a decade earlier was creating cars that cost more than a modest home of that era.
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    unclogum Dec 11, 2010 2:19 PM
    Dcaddydan you of course are right , Folks that resort to name calling always earn our respect and we the readers believe you are well educated and will take your opinion and put it where it belongs
    Report This
    insightinsound Dec 11, 2010 2:15 PM
    tcdclark ----- Gm applies that technology (which I believe was developed initially for industrial use and "Diesel/electric" locomotives) quite well in the case of the Chevy Volt... that's exactly how the work... only with gasoline rather than diesel, because of the lower polution issues with gas.
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    tcdclark Dec 11, 2010 2:03 PM
    Diesel engines are used to generate electricity for the electric motors that power the huge mega cruise ships. There's no reason that this same technology can't be used in the auto industry, other than cars will be too efficient and then what would the powerful and wealthy oil industry do.
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    dcaddydan Dec 11, 2010 2:03 PM
    unclogum- Are you honestly comparing this awesome fine looking piece of machinery with a lousy ugly Corolla? How do you know its a electrical nightmare when the dam car with this option is not even on the road yet. Your a joke!
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    avalosdebra Dec 11, 2010 2:02 PM
    i think makeing all these new cars is a waste of time when most everyday person could not afford them anyway , so to me a waste of time and money knowbody has.why couldnt they improve the cars we allready have not to mention the coast of getting these new cars fixed is almost buying a new car all over again what a joke the car companies are pulling on the everyday person, all i can say is if you have the same payment on a car you do a house payment or even rent is way beyound me. and some of the prices they have on cars its like buying a house which id rather buy and get a cheap car that i could go to the junckyard or aouto service store for a part and do the work myself. my opinion
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    insightinsound Dec 11, 2010 2:02 PM
    surfundeep ---- ********** what solving this problem will require is for someone like yourself doing the research and developement necessary to eliminate these issues which Are NOT Inherent in the process of the electro-magnetic conversion, but rather are aberations created by an inappropriate design for mechanical application of the principle(s) involved.
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    thkayaker Dec 11, 2010 1:58 PM
    we dont need hybreds, i had a ''73 transam with a [455, 4 bbl],at. that got better mpg than a lot of 4 cyl. cars - almost 30 mpg. my uncle tells me he had a lincon continental with a 460 [69-72] that got almost 30mpg... i had a ''72 fiat spider that got 35 -40 mpg[4 cyl.] and ''85 honda crx were getting [50 mpg]. these were just regular cars, they didnt require a phd or dr?? to repair/maintain. [[[the car companys just want to get your money[all of it],,,,, part when you buy it - the rest when it needs repairs.
    Report This
    drmumpower Dec 11, 2010 1:58 PM
    My 1989 big and comfortable Buick LaSabre got 33 highway mpg w/o air on and 31 with air on. That car was amazing. My 1993 LaSabre with the same six cylinder engine dropped by 5 mpg.
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    unclogum Dec 11, 2010 1:50 PM
    Lets say this electrical nightmare is 30k and my Toyota Corolla is 17k loaded. That's 13k I could spend else were. Corolla gets 35 mpg or better always , not bad. In 10 years it will be worth more than the Buick , perhaps 5 years. The guy in the Buick will have spent well over 13k with interest , repairs and added insurance cost. I on the other hand will still have that money. That's common sense folks and why I retired dept free at 57.
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    insightinsound Dec 11, 2010 1:43 PM
    surfundeep ----- My guess is that GM will use a heat-pump on the Volt as they did in the EV1. More efficient than an electrical heating element.
    Report This
    surfundeep Dec 11, 2010 1:37 PM
    insightinsound: I appreciate your point about regenerative braking, but as a Lexus tech, one of our most frequent service items is replacing pads and rotors about every 10-12k on our line of hybrids. The Rx 300-330 line eats them faster than the others. Techs I know from Honda/Acura report similar wear. Customers feel blindsided that their brake systems wear out so fast.
    Report This
    planetoysz Dec 11, 2010 1:36 PM
    insightinsound Dec 11, 2010 1:19 PM planetoysz --- I appreciate the civilized exchange, which enables a true discussion. What I am saying is that The full scope of producing a hydrogen fuel cell is much more energy-intensive than most citizen realize. Also I'm quite certain you will find that there is substantial water vapor produced (at least at current technology capabilities) as a by-product of the opperation of the Hydro-Cells...... You are correct about my being a little "light" on chemistry per sey, however I am an electronic engineer with a substantial background and foundation in physics. I too take you points... they are Not Contradictory to my points... and both of our concerns need to be considered as motive developement proceeds into thyis century........... ............ Again we agree and I appreciate the discussion as well. I don't know how some of my words end up blanked out; They must have some non-English speaking moderators doing some things today :-) This has been nothing but a civil dialog. I'm not an expert either and, like you, have most of my background in electronics, electro-mechanical and some physics. I just think there are atmospheric and naturally occuring means for dealing with water vapor and that the issue, while worth noting perhaps, is a very minor one, considering the alternative :-) No matter what gets done, there will be a waste product of some kind. That's the nature of almost everything that is converted from one thing (energy) into something else (mobility) whether it be natural or man-made. Let's hope that the waste products can be engineered into the process in a way that doesn't counter our existence :-) Gotta go.... It's been a good discussion!
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