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Folks,

The architecture of the Volt lends itself to a wide variety of engine types. The engine in my '15 Volt is a standard (Otto cycle, I believe) engine.

But, you could use the Atkinson cycle engine (the Prius uses it) which is more efficient. Or a Diesel could be used. Or, a small turbine engine could be used. Or an external combustion engine (a steam engine) of some sort could be used. Or a fuel cell could be used, bypassing motion entirely. Or, a natural gas engine that is tuned to make use of the very high octane of natural gas to be more efficient.

Having the large battery means that whatever engine you are using doesn't have to be as immediately responsive as a typical car engine, so a steam engine or a turbine engine could be used. For example, when the car sees that it will be running out of battery juice, it could start up a steam engine 5 or so minutes before it's needed. Torque at low speeds isn't an issue because you can run the engine at whatever speed you wish to power the generator.

I know that GM went with what they knew, but could there be a range extender that takes advantage of the big battery in the system and uses that to make the system even more fuel efficient.

Thoughts? Comments? Am I smoking the good stuff, or is this viable?
 

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Engineering is the art of meeting a specification, within a cost constraint, any of fuel sources you listed could be configured to work with electric main traction, and is done, look trains and buses.

Your listed options are not done as what was done was considered the most marketable solution for a passenger car. The stanley steamer has been out of production for 100 years, good luck getting the NTSHA to allow steam boilers in on the road vehicles, all the others have down falls as well compared to what was produced for the Volt.
 

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Often it's the case that perfection is the enemy of good enough. As I understand it, GM is taking an incremental approach here, possibly with an end-game in mind, without being tempted to overdo it at any given step. The generation 1 engine was one that was readily to hand and helpful in eliminating another large challenge on top of a nearly-too-large pile. For generation 2-- with the luxury of time and money being available-- the engine has been put in the spotlight a bit more, with a lighter, more purposeful thrasher (reciprocating) engine still being the suitable compromise along the lines Henry_FL mentions. Now with the Bolt on the horizon caveman engines (something burning under the hood) are being pushed increasingly toward niche status for the purpose of light transport applications. Will we see another iteration of shuddering flaming-and-or-exploding temporary expedience developed by GM for the purpose of keeping one foot solidly in the grave? It's hard to say, but swerving heavily into fundamental and risky development of a known dead-end method seems unlikely.
 

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Folks,

The architecture of the Volt lends itself to a wide variety of engine types. The engine in my '15 Volt is a standard (Otto cycle, I believe) engine.

But, you could use the Atkinson cycle engine (the Prius uses it) which is more efficient. Or a Diesel could be used. Or, a small turbine engine could be used.
Thoughts? Comments? Am I smoking the good stuff, or is this viable?
You need a Gen II volt, it already uses an Atkinson cycle (at least as much as a prius is Atkinson)

I would love to see a little diesel volt but sadly we would need to alter law and policy in this country to make it happen.

Turbine is like a unicorn, they are best used on big vehicles and even then can have a reliability in minutes, they always seem to be 10-20 years off, not because they don't work but due to cost and reliability.
 

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I'd rather see the next iteration with a Mr. Fusion as a power source. Of course we also need to add the flux capacitor option and store your hoverboard in the hatch.
 

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Engineering is balancing tradeoffs, all of the above have been considered at one time or another.
 

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Baby steps really... the volt is a great car (I'm excited to hopefully take delivery of my 2017 here in 2 or 3 weeks). Most of the public has no clue about what it is, what it can do, and how awesome it really is. Combine the lack of knowledge with more exotic things like a jet engine, fuel cell, etc, then people go from being indifferent/unknowledgeable to downright scared due to it being "so different"

Once electric vehicles really take hold and are mainstream embraced, then you can branch out and try different more exotic methods.
 

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You need a Gen II volt, it already uses an Atkinson cycle (at least as much as a prius is Atkinson)
+1 You can't afford a special engine for every application and modern engines get tuned for the task at hand. Eighty percent of the benefit for twenty percent of the cost.
 

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Folks,

The architecture of the Volt lends itself to a wide variety of engine types. The engine in my '15 Volt is a standard (Otto cycle, I believe) engine.

But, you could use the Atkinson cycle engine (the Prius uses it) which is more efficient.
I am under the impression that the Gen 1 Volt does have an, 'Atkinson cycle ICE', which in this case, means the cam profile and duration is optimized similar to Atkinson performance and economy.
Apart from it being limited to 4800rpm, this is why the 1400cc motor is only producing 63kw. A modern twin overhead variable cam 1400 should be heading for twice that, even without a turbo.

I'm keen on the turbine engine option.
Here is an example of how I'd like to do it:
https://nikolamotor.com/one
 

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A turbo like the Caddy CT6 would be really good for performance. 3-clutch tranny can use additive ICE and EV power.

There is no way GM can afford to use a totally different ICE (or whatever) just for Volt. The 1.5 and previous 1.4 are used in other vehicles thereby giving economy of scale.
 

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The beauty of the Volt is that the range extender is familiar and convenient to use with today's infrastructure. If you start getting into concepts that are more difficult or inconvenient to refuel, range anxiety starts coming back and the real value of an EREV is lost.

The cost points already made are huge too.
 

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No matter what the illusion is, there are very few >42 mpg combined cars with the punch a Volt has.

Other than the Prius, slow ass cars don't sell well. In fact, the Prius does not sell well in the grand scheme of things.

The Volt is roughly 20% heavier, 20% quicker, and has 20% worse gas only fuel economy than a Prius with it's "Atkinson" engine.

Which makes absolutely no sense whatsoever. What are you gaining by running the A-cycle? The low weight and low power are what gives it better fuel economy.

The new Chevy i4 is perfect for the application. Good acceleration (mostly due to good engineering), good fuel economy, good all electric range, good gas range.

Put a tiny battery and electric motor in the Volt, it would weigh and perform like a Prius. But who wants to suffer for a couple bucks a week?
 

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GM seems to be in a very good position to transition into a different design range extender whenever it becomes viable and whatever it may be. That seemed apparent to me even before Gen 1 was for sale.
 

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Strangely I believe a diesel would be a bad choice, takes far longer to warm up than a gas engine, and in the intermittent operation of a Volt would not be as fuel efficient. Although I find driving a 2l 140hp C-Max diesel 6speed auto very quiet and lots of torque so not against them.
 

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I'm a diesel nut. However, I don't believe a diesel is a good fit for the Volt.

1) Price. The car price would jump.
2) Weight. A diesel of the same HP weighs more than a gas engine.
3) Range Extender Theory. Diesel is less common in the US than gasoline. Having a range extender that you cannot fill up in a severely out-of-the-way location defeats the purpose.
4) The EPA and CARB's hatred of diesels. In California, we actually had a "scientist" (he bought his PhD online) who falsified a study to prove diesels were more harmful than they really were. They still use his false data even after he was caught and punished. They did not fire him for lying about his PhD. Being anti-diesel is a badge of honor and a prerequisite in the EPA and CARB.

That being said, I'd rather have a diesel range extender in the Volt. Diesel is currently cheap, and it gets 20% more range per gallon. It's low RPM and high torque is perfect for generator functions.
 

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Turbine is like a unicorn, they are best used on big vehicles and even then can have a reliability in minutes, they always seem to be 10-20 years off, not because they don't work but due to cost and reliability.
Chrysler had a functional, reliable, and pretty efficient turbine. But people didn't like learning how to drive differently and the thing got canned. (Every teen in the country knows how to do a brake stand when they're showing off, but somehow it was not acceptable for the car to require it at every stoplight...)
 

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The beauty of the Volt is that the range extender is familiar and convenient to use with today's infrastructure. If you start getting into concepts that are more difficult or inconvenient to refuel, range anxiety starts coming back and the real value of an EREV is lost.

The cost points already made are huge too.
^ This. Efficient, clean travel is provided by the traction battery. The purpose of the range extender is different. It offers the most familiar power source to take away the objections of potential buyers nervous about something different. If you can't fuel it exactly like your last car at every gas station, it doesn't perform that function.
 

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Based on the OP comments I'd say a small engine, say, 650 cc should be enough with that big battery. Maybe an off-the-shelf motorcycle engine would work. Yeah, that's it. GM are you listening?
OK, I apologize......
 

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Discussion Starter #20
Chrysler had a functional, reliable, and pretty efficient turbine. But people didn't like learning how to drive differently and the thing got canned. (Every teen in the country knows how to do a brake stand when they're showing off, but somehow it was not acceptable for the car to require it at every stoplight...)
But that is my point! Having a battery and motor that can put out 110 kW, you can get instantaneous power and let the computer control the turbine engine. So, a brake stand wouldn't be needed.
 
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