A Hybrid I would drive (and it's American!) - The Capstone CMT-380

D

D-Fence

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So.

You have the following scenario.

- You are Capstone, one of the worlds leading manufacturers of micro turbines
- You happen to get the Electronic Arts Creative Director to work with you
- A spare Factory Five Kit Car

WEEELLLLLLL


Meet the Capstone CMT-380 Hybrid.


capstone-turbine-cmt-380-concept-car_100233902_l.jpg


An electric car with a range extender. Which happens to be a turbine. Running on Diesel or Biodiesel and generating 30kW. And excells in meeting the Californian Emissions Crap Law.

Won't be fast, that, right?

0-100km/h: ~4s
Topspeed: ~240km/h
Range: Electric: 130km. With Range Extender: 800km

And you can charge it on every household line....

I would drive that. Seriously. How cool is that.

"I drive a Hybrid. With a turbine. Which runs on Diesel. And I just outran you."

*head explodes*
 
... and how much Diesel does it use for the 670km it has to do on Fuel? Is the miliage very poor? I?m asking because they don?t give that number and nobody?s put a diesel-microturbine into a car before to power an electric motor AFAIK, so I kind of guess that is because the efficiency is bad. That would be a shame for an otherwise brilliant Idea ...
 
Turbine generators have been tried in hybrids before. The EV1 had a serial hybrid drivetrain variant (experimental only) that had a turbine as the on-board generator. It was gasoline powered, but turbines really don't care what they run on so long as it's liquid and flammable (yes, they will run on vodka), so 'diesel' isn't entirely true.

Apparently it got some stupendous number of MPG, but it was canned by GM because it was deemed 'too complex.'

My own preferred drive system would be a serial hybrid with a turbine generator and four hub centric motors (or, for unsprung weight, mount them just inboard and connect with driveshafts). This is getting close; such a system in something like an SUV could quite literally go nearly anywhere under any circumstances and burn any liquid fuel available, including corn ethanol.
 
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I'd drive that hybrid too if the numbers are right. I don't care about gasoline, Diesel, LPG, CNG, electric, hydrogen, hybrid or whatever as long as the car is good as a car.
 
efoolution said:
So the mileage (or rather the produced engergy/per litre fuel) is very good? :blink: That would be awsome. Turbines are pretty simple things compared to a internal combustion engine too so it shouldn?t be too bad when it comes to repairs/maintenance ...
Click to expand...

Turbines can be enormous fuel hogs or they can be very efficient. There's a trick to it.

When turbines have been tried as direct-drive prime movers (such as in the Chrysler Turbine Car), they have been found to have the world's worst case of turbo lag and to be huge fuel hogs. Turns out that it takes a lot of fuel to spin a turbine up (or 'accelerate' it) and they just drink fuel at low power settings. However, if you could somehow contrive to run the turbine at a high static RPM (such as on an airliner) they become fantastically efficient at producing power from a given amount of fuel. This was a problem, since a direct drive turbine has to spin up and down constantly as one drives through traffic. This problem was unsolvable at the time and is why the turbine cars never really went anywhere - they didn't offer any significant advantages (from the manufacturer's point of view) and actually consumed more fuel than a comparable piston engine overall.

Enter the hybrid concept, specifically the serial hybrid concept, which was actually a derivative of the old Gas Turbine Electric Locomotive concept. This uses an engine running at a static RPM to generate electricity which then powers the car. The engine RPMs don't go up or down (much with load) and as the GTELs proved, a turbine optimized to run at a set RPM will run at ridiculous fuel efficiency for the power output. A turbine is also smaller, lighter and cheaper to maintain than a piston engine of comparable output. It requires less lubricant and it requires it less often. In a serial hybrid, the major Achilles heel of the turbine, throttling it up or down, is minimized as the turbine fires up when needed, runs at its most efficient RPM (100% throttle) to generate electricity to charge the batteries up and shuts down when a predetermined charge point is reached.

Just for comparison, the maximum thermodynamic efficiency of a petrol piston engine is around 25% to 30% percent, a diseasel piston engine can hit as high as 40%... but a gas (not gasoline) turbine operating at a static RPM setting easily hits 60%. What this means is that even in the most efficient driving regime, 60% of a litre of diesel in your car goes out the tailpipe as heat and doesn't propel the car at all. In a turbine running flat out, only 40% or less goes out the exhaust unused.
 
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With this, you can run the turbine constantly at her highest point of efficiency, and the efficiency of a turbine is friggin high compared to an internal combustion engine, as Spectre said. As well, if you could somehow recover the turbine heat as well (like BMW & GM experiment right now: http://www.autoblog.com/2009/03/10/bmw-working-with-nasa-on-regenerative-exhaust-system/ ), you can boost that even more.
As Spectre said, as long as a turbine is run constantly at the highest efficiency point, it is brilliant.
 
The Capstone microturbine that's used in this car already has a production-proven recuperator, which recovers the turbine heat to aid efficiency:

GasTurbine.jpg
 
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So how can I buy one?

or will it vanish forever right before the company can prove it's abilities? :D
 
Night_Hawk said:
So how can I buy one?

or will it vanish forever right before the company can prove it's abilities? :D
Click to expand...

It's unlikely that the tech will vanish; the system this is based off of is currently being used in the newest generation of New York City and Baltimore buses, with several hundred in the order queue at present:

http://en.wikipedia.org/wiki/Designline

http://en.wikipedia.org/wiki/Capstone_Turbine

Of special interest is that these microturbines have only one moving part and use no lubricating oil whatsoever.
 
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I think he's referring to all those legends of the 100 MPG carburetor or other mystical mileage-boosting devices that were silenced by GM or Exxon or some other scapegoat right before they could hit the market. Who knows what GM could do with taxpayer money now, the conspiracy theorists mutter.
 
Labcoatguy said:
I think he's referring to all those legends of the 100 MPG carburetor or other mystical mileage-boosting devices that were silenced by GM or Exxon or some other scapegoat right before they could hit the market. Who knows what GM could do with taxpayer money now, the conspiracy theorists mutter.
Click to expand...

Well, GM's about to be boned again anyway. Toyota just announced that the Plug-In Prius, their counterpart to the Volt, will go on sale in 2011 and cost only $23000. Compare that to the Volt at $40K... and you're left to wonder, just who would buy a Volt?

In any case, this technology is out in the open and governments are buying it, so I doubt it'd get canned to be filed along with the mythical 100mpg carb.
 
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Concerning mpg, a quick google of cmt-380 and mpg shows a wide speculation range of anywhere between 40 and 200mpg... I'd say nobody knows yet.
 
narf said:
Concerning mpg, a quick google of cmt-380 and mpg shows a wide speculation range of anywhere between 40 and 200mpg... I'd say nobody knows yet.
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The GM EV1 series-hybrid turbine prototype was known to get between 60 and 100mpg. That was with much older generation technology, so despite the larger vehicle this system is in, it's probably going to be at least in the same ballpark - which will dwarf even the current fuel economy champs.
 
Spectre said:
Just for comparison, the maximum thermodynamic efficiency of a petrol piston engine is around 25% to 30% percent, a diseasel piston engine can hit as high as 40%... but a gas (not gasoline) turbine operating at a static RPM setting easily hits 60%. What this means is that even in the most efficient driving regime, 60% of a litre of diesel in your car goes out the tailpipe as heat and doesn't propel the car at all. In a turbine running flat out, only 40% or less goes out the exhaust unused.
Click to expand...

http://www.microturbine.com/_docs/C30 NATGAS.pdf states an electrical efficiency (ie the figure we are looking for when charging our battery) of 26% :(
 
narf said:
http://www.microturbine.com/_docs/C30 NATGAS.pdf states an electrical efficiency (ie the figure we are looking for when charging our battery) of 26% :(
Click to expand...

That's the natural gas turbine, not a petrol or diesel fired one. When I say 'gas' turbine, I mean something that compresses a gas (i.e., air) as opposed to a steam turbine. A natural gas fired turbine is less efficient than a petrol or diesel fired one, just as with piston engines.

While I hate using GM as a yardstick, they did dump a lot of money into the EV1 program. Of further note is the diesel parallel-hybrid variant prototype, which achieved 'only' 80mpg. GM basically proved that the turbine *could* be ~20% more efficient, which bears out the numbers above.
 
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Spectre said:
That's the natural gas turbine, not a petrol or diesel fired one. When I say 'gas' turbine, I mean something that compresses a gas (i.e., air) as opposed to a steam turbine. A natural gas fired turbine is less efficient than a petrol or diesel fired one, just as with piston engines.
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As you wish :tease: http://www.microturbine.com/_docs/C30 Liquid Fuel.pdf claims 25% electrical for diesel, kerosene, bio-diesel :(
 
narf said:
As you wish :tease: http://www.microturbine.com/_docs/C30 Liquid Fuel.pdf claims 25% electrical for diesel, kerosene, bio-diesel :(
Click to expand...

I just went and looked - that doesn't seem to be all that clear on the graph. There's no axis labelled "percent efficiency" on the second graph. That also doesn't seem to be borne out by similar products made by other companies.

I wonder just what they mean by "net efficiency", because if it's thermo efficiency, it seems awfully low. Might be worth calling them later today and asking, I suppose.
 
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