Showcased in the Saab 9-X concept at Geneva, GM's unveiled their fifth hybrid powerplant: an evolution of their first-gen Belt-Alternator-Starter system (a.k.a. BAS or "mild hybrid"). The Detroit News says upgrades include a new, Hitachi-sourced lithium-ion battery, a new electric motor, the addition of "brief electric-only propulsion" and improved regenerative braking. At Geneva, GM hybrid guru Steve Poulos said these upgrades do not an American Revolution make. "We took the same [first-gen BAS] system and put it on steroids." GM's next gen system is three times more powerful than the existing BAS unit. That said, Poulos admitted that the new system will improve a BAS-equipped vehicle's fuel efficiency by one to two miles per gallon. CEO Rick Wagoner says this new drivetrain is "important step to make hybrid technology more affordable to a wide variety of consumers." Baby steps indeed. If GM wants to catch-up with Toyota's Synergy drive, they'll have to do better than this.
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This actaully seems somewhat promising. I agree that GM’s current mild hybrid systems are sort of imposters and maybe dont deserve a hybrid badge. However, the price of admission for these mild hybrid systems is very low. If GM has improved the efficiency where a 4cyl application is seeing a 20% improvement in fuel efficiency over its non-hybrid counterpart, and it costs very little, seems fairly promising to me.
Add this new system to a small displacement engine with direct injection and turbo and you could see some really serious fuel economy at a very reasonable price. That’s nothing to scoff at.
It’s due in 2010 – another example of premature specification.
Ed,
Their press release quoted a 20% improvement in mpg.
If your Malibu is getting 25 mpg combined cycle and you improve that by 20% then you’ll get 30 mpg combined cycle.
I was never that good at math, but that is a 5 mpg improvement AND 5 mpg is greater than “one or two mpg.”
What gives?
What is the cost premium of this system over that of a non-hybrid? Sticker for sticker, the Saturn Vue looks about $3,000 more expensive than the base 4-cylinder…. however you do get other options with the hybrid that aren’t on the base so it’s not clear cut.
The mileage for the hybrid Vue is also 25/32 compared to 19/26 for the non-hybrid…. so the fuel savings aren’t minor.
Theoretically if the new BAS system offeres 1-2 mpg over the current one, that puts the Vue at 27/34…. not too bad for a 3900lb SUV.
One last thing, if you look at the torque curve of the 2.4 litre Turbo/Hybrid, the curve is higher than the 3.6 litre VVT across nearly the entire powerband. It also gets nearly 100 ft/lbs more torque at 1,700rpm than the standard 2.4 litre turbo. With the proper gearing, that should provide plenty of scoot and still return good efficiency.
If I read this correctly, the alternator/electric motor will power the vehicle for “brief” periods of time using a rubber belt? This brings back memories of the first cvt’s that used rubber belts.
Just give me a good turbo diesel in a compact car like the Astra please… Okay? Much better mileage without all the black magic. I don’t trust GM black magic quite the same way I trust Honda black-magic…
Do I understand this correctly? A motor/alternator is going to power the drivetrain for a short period? Why is it that the Asians sandwich a motor/alternator into the flywheel?
See what I mean about GM black magic vs Honda or Toyota black magic?
Oldsmoboi: the 2.4L engine in GM vehicles is not a turbo in either Hybrid or non-hybrid configurations.
So the “brief periods of acceleration are from” when the overgrown starter/alternator using a belt turns the engine in order to give power to the wheels. You’d only hope that they somehow build the engine so that the valves stay open while the elec motor is turning that engine in order to get power to the wheels.
I bet those drivers can get better than the 1-2 mpg just by driving slower and more carefully to manage traffic and reduce stops. GM should take credit for that idea and call it the 1 mode hyrid.
After having spent a few hours mired in bumper to bumper, stop and go..mostly stop… Chicago traffic last fall….ten lanes across, I saw the value in even this sort of light hybrid approach. Not all of us breeze into work and back cruising at efficient speeds. Stopping the frigging motors when not needed makes huge sense, for little extra cost.
They show one in the graphic accompanying the press release for this system.
The idea behind shutting off the motor as soon as you are stopped and starting it back up as soon as you need it to has always seemed like an excellent idea to me, Hybrid or no hybrid. If perfected, this could significantly increase city gas mileage on any vehicle out there.
On top of that, dynamic engine power managements should be placed on every engine out there. These technologies could save any engine a significant amount of gas Before adding any sort of hybrid system.
Of course, programming the software will take skills, and I can only imagine how annoying it would be on the consumers to have to update their cars firmware every other month for better gas mileage (because, like any software, you know it would be rushed too quickly). I can also see dealer “fees” on top of this…
I guess all cars I’ve ever owned are some kind of hybrids. You see I can turn a key to the “off” position and the engine shuts off. I pay attention to the lights and turn the key to “start” and the engine starts right back up and I can drive. This system is amazing as it costs $0 to install and supposedly every car has one – except for those cheeky cars with push buttons instead of keys.
who’s going to fix it and what will it cost to repair? 1 – 2 MPG advantage gets eaten up real quick when the dealer tells you the repair is not covered under warranty. I bet that little gizmo is several thousand dollars to replace.
people don’t want cars that shut off at red lights. that is not their idea of a running car. Add to that the lack of AC in the summer, or a heater than cools off in a traffic jam in the winter. can this be overridden in an emergency, like stuck in a snow storm on a PA highway for 16 hours? Happened last year to a bunch of folks.
You know what would be a cheap solution and save gas, adapting the cylinder deactivation technology we already have to shut down 75% of the engine while stopped or moving less than 5 mph. No reason to run a 200 hp engine while it’s not doing anything except running the accessories and it can kick in the rest of the power when you actually start moving past 5 mph.
I like the idea of these stop/start systems to save gas, but I don’t like the added weight, complexity and being able the ride the Hybrid bandwagon because it has a bigger starter/motor.
From reading a different auto site I understood GM’s new BAS to do without a starter motor altogether. The Alternator-on-steroids can silently start the motor the moment you lift off the brake. Once the engine is spinning (the alternator is turning it via the accessory belt) then it adds spark and fuel and, voila, the engine is running. For that period of time when there is no spark or fuel, the car is moving under electric power only — unlike the last GM BAS. Same thing under decel, the ‘starter’ then acts as an alternator, creating drag to recharge while the engine is being spun without fuel or spark.
On paper, this looks like a great idea that could benefit ANY car.
GM produced a chart at Geneva that outlined that, with the alternator assist, a direct-inject turbo Ecotec 4 cylinder produced more torque than their 3.6L V6 from idle to redline while getting significantly better fuel economy. I’ve driven a couple cars with the 3.6 and it’s no slouch. A midsize car (Malibu?) with the DI turbo and new-and-improved BAS and, say, 28mpg combined sounds like a great combo. I wish Honda or Nissan would do one.
Electric only via the S belt? Am I the only one who thinks this might not be the best idea?
The BAS hybrid systems have to turn the entire engine over before turning the wheels. Engines have pumping losses and if they don’t open valve during the compression stroke they are using most of the battery just to pump the engine over. The Honda / Toyota hybrids have the drive system mated to the flywheel or the transmission itself and when their electric motor turns the wheels of the car the engine is off completely. This is why they do so much better than BAS hybrids and why the gains are so minimal.
Anyone ever seen the bud light caveman commerical where they had a cooler made out of a rock to carry their cold bud light? Then one caveman invents the wheel to help with moving their cooler – only to use the wheel as a tray to put the cooler on top and carry both items (rather than put it on the ground and spin like a wheel and make a wagon). GM’s level of thinking on hybrids.
You know what would be a cheap solution and save gas, adapting the cylinder deactivation technology we already have to shut down 75% of the engine while stopped or moving less than 5 mph.
I’m not sure this is always feasible. GM looked at putting cylinder deactivation on the 3.5 OHV engine, but apparently it created an unacceptable amount of vibration.
I’m looking forward to the HCCI engines that GM and others are working on, though. It sounds like very promising technology, especially if paired with a mild or full hybrid system.
Not to mention the larger diameter of the flywheel is going to have a better efficiency (leverage) than the little alternator pulley…
I say all this drawing on some big conclusions without seeing the Asian flywheel motor/alternator design.
Would be nice if there was some way to add a clutch into the flwheel assembly so that it would not be necessary to rotate the engine at all when the electric motor was working. Of course that introduces another level of complexity but I’ll bet that clutch would last the life of the car (200K miles) since it would not be mating a 1500+ rpm engine to a stationary transmission input shaft. It would be mating a stationary crankshaft to an electric motor turning a few hundred rpm. Heck, roll the engine over on battery power before you mate the electric motor shaft and the crankshaft… Yep this armchair designed hybrid is getting out of control. Still you could roll the engine over with one of these alternator/motors to match the speed of the flywheel motors before engaging the two shafts.
Frankly I’m ready for a full hybrid – a small diesel engine charging batteries based on a throttle position chosen by a computer (which learns the best efficiencies based on a laundry list of data indicators) with electric motors providing all of the vehicle motion. May not be the method best suited for all vehicles but it would certainly be fine for my daily commuter. Best of all I could go full stealth for say 50-75 miles and that would be plenty to get me home where I could recharge.
Maybe the DeWalt/Porter-Cable guys will release a full hybrid before the car companies…
What is the cost premium of this system over that of a non-hybrid?
The Detroit News article simply says that the cost will be “roughly the same.”
That’s the point of BAS – provide some hybrid benefits without all the extra cash. If GM can improve it by 1 or 2 MPG every cycle, hey, more power to em. Ultimately I think it’s good not to have all your eggs in one basket.
And what was GM’s old saying back when there was brand differentiation? “A car for every budget and taste”? Well, maybe they want to have “a hybrid for every budget and taste.” And BAS has a better shot of becoming ubiquitous than a full-blown hybrid in the short term.