GM brings back 1.0L ICE! - in the Volt plug-in series hybrid :)

[MetroMPG]

Detroit Auto Show: It's here. GM's plug-in hybrid is the Chevy Volt Concept

In spite of the presence of an internal combustion engine, GM does not call this vehicle a hybrid. In fact, they consider it an EV with range extending capability. The engine is a turbocharged, 1.0L three cylinder engine with 71 hp that has no mechanical connection to the wheels. The ICE runs at about 1800 rpm and drives a 53 kW generator that charges the lithium ion battery pack. The engine starts and stops automatically as needed to charge the battery.

Of course, the achilles heel of the concept is the L-ion pack. Issues of cost and durability of nanotech versions needed to make this a feasible battery remain to be settled.

[MetroMPG]

GM claims a 640 mile range on 12 gallons (US) = 53 mpg (US)

Presumably the first 40 miles are electric.

[Rstb88]

the whole concept of using an ICE as a generator for an electric motor, completely confuses me. I guess I have too much of that 'Gimme a V8' in me but it just doesn't make sense. If the ICE is at a continual 1800rpm why is there a turbo when there will be very little spool time. And would it not work just the same w/o it, or would it not create enough energy to charge the batteries w/o the turbo. Also what kinda of fe technology is put into that one litre engine. Hopefully its the same design as the one that came out of the Metro.

[landspeed]

71bhp at 1800rpm is pretty impressive!. I guess the turbo is designed with larger vanes to spool up with, so, it can run at full boost at 1800rpm. If they then used an engine design with e.g. specially shaped pistons, and combustion chambers, they could have stoichometric or even lean burn without detonations, and a suitable cat if it is lean-burn. This would reduce pumping losses, and mechanical losses, running at high output, low revs, and
no pumping losses.

The only issue is the 53kw generator - that would be 5300 amps at 12V, or 530 amps at 120v. Could the batteries take this recharge rate?. If so, then re-gen braking would be no problem at all!

Edit : only 53mpg?

[MetroMPG]

Originally Posted by landspeed

Edit : only 53mpg?

Found some more info:

The five-seat car would be able to travel as fast as 120 mph, and run at 70 mph for up to 640 miles while consuming only 12.8 gallons of gas to fuel the generator, said Jon Lauckner, vice president of global programs for GM. That's 50 miles per gallon, with the gasoline-powered generator running about half the time

http://www.latimes.com/business/la-f...home-headlines

Of course, on shorter trips, or at lower speeds, its gas MPG would be significantly higher.

[Silveredwings]

I think that is exactly what the consumer needs: an EV with 40 mi range that can be extended with gas. It's pretty much a plug-in hybrid-electric veh. but maybe GM is trying to save face by calling it an "EV with ICE" since Toyota will likely beat them to market with a PHEV. Or maybe it's just another in a long line of car show teases.

Maybe a configuration like this one is the 'future' regardless who does it first. Car design would be so much more modular and quicker to market once the necesary components are available. Improvements on it might include replacing the drivetrain hardware with 4 lightweight hub motors and a maybe a diesel generator in place of the gas one. Performance cars could have ultracaps to more efficiently capture regen energy and also 'stiffen' the battery pack for high amperage launches. It's nice to dream...

[Silveredwings]

Originally Posted by MetroMPG

Of course, on shorter trips, or at lower speeds, its gas MPG would be significantly higher.

From looking at that boxy shape, I bet it will need some aero 'calibration' to meet those kind of numbers at 70 mph.

[landspeed]

Originally Posted by Silveredwings

From looking at that boxy shape, I bet it will need some aero 'calibration' to meet those kind of numbers at 70 mph.

At first glance, I would agree, however... It has a reasonably aerodynamic rear,
with a gentle roof slope and it looks like it has slight boat-tailing. Also, it has a small frontal area - if you look at the size of the wheels, you will see how small the windows etc are .

Edit : also, the mirrors are raised slightly above the place of highest airflow if you
look closely!

[red91sit]

Originally Posted by Rstb88

the whole concept of using an ICE as a generator for an electric motor, completely confuses me. I guess I have too much of that 'Gimme a V8' in me but it just doesn't make sense. If the ICE is at a continual 1800rpm why is there a turbo when there will be very little spool time. And would it not work just the same w/o it, or would it not create enough energy to charge the batteries w/o the turbo. Also what kinda of fe technology is put into that one litre engine. Hopefully its the same design as the one that came out of the Metro.

I'm also confused by this. The little motor does make 207 lb/ft of torque, but wouldn't it be FAR more efficent if it was connected to the wheels? Then it could maintaing near W.O.T. to charge the batteries and move the vehicle until the batteries are full charged then it turns off until say 50% S.O.C.

Right now that little motor has to go through all of these reactions
(gas)chemical->
(engine) mechanical->
(generator) electrical->
(battery) chemical->
(motor) electrical->
(wheels) mechanical

that has to suck the efficeincy right out the window.

[MetroMPG]

Originally Posted by Silveredwings

maybe it's just another in a long line of car show teases.

THAT is the salient issue, yes. I'll believe it when I see ... my neighbour buy one

Aero-wise, the most apparent mistakes are the 20 inch chunky wheels and the massive fender opening/flare to accomodate them.

Aside from the backlight angle (good) and high deck (good), the rear of the car actually sucks from a boattailing perspective because of the wheel size/style & fender flare, and the fact that the body essentially stops at the rear wheels (so no opportunity to taper past them).

On the bright side, IF this ever makes it to market, it won't come with those giant wheels. We'd see normal 15 or 16 inch ones. So they'd have the opportunity to clean up some of these issues.

And ideally, since that ICE isn't driving the wheels, it could be in the rear, so the front grille could be minimized, the underbody cleaned up, and the cooling air flow could be ejected into the wake to increase its pressure. Just like the Precept PNGV concept.