[BADDASSC6]

http://money.cnn.com/galleries/2010/..._hybrid/2.html

This is great! This is a honest improvement that will not help destroy the Earth. My big problem with Hybrids are the batteries and extra weight they bring. Inertial energy storage systems have been kicked around F1 teams, but where not allowed. Now Porsche is bringing it to sportscar racing! It kinda works with the ass heavy nature of the 911s. I still think that the future of cars is in direct drive electric motors with gas turbine generators, but we'll have to wait.

[Vettezuki]

Originally Posted by BADDASSC6

. . . I still think that the future of cars is in direct drive electric motors with gas turbine generators, but we'll have to wait.

I think there's actually a guy here in CA that has done that on his own.

No hydrogen fuel cell?

[BADDASSC6]

No fuel cells. They are going to cause more problems than anything else. Turbines are smaller, lighter, and more powerfull than recipicating motors. couple that with electric drives and you have something viable. No trans. a turbine motor essentially coupled electrically to the wheels.

[SeanPlunk]

Originally Posted by BADDASSC6

No fuel cells. They are going to cause more problems than anything else. Turbines are smaller, lighter, and more powerfull than recipicating motors. couple that with electric drives and you have something viable. No trans. a turbine motor essentially coupled electrically to the wheels.

Forgive my ignorance, but what's the limiting factor? Is it cost, size, or both?

[Vettezuki]

Originally Posted by SeanPlunk

Forgive my ignorance, but what's the limiting factor? Is it cost, size, or both?

For fuel cells or the turbine combo?

For fuel cells it's at least a few obstacles.
1 - Cost. They typically use platinum as part of the fuel cell construction (forget the exact combination of properties why). The upside is there is some nano-tech substitutes that have the potential for being dirt cheap but is still a ways off.

2 - Efficient production of hydrogen. It may be the most abundant element in the universe, but it doesn't grow on trees here on earth. Typically it's dissociated from water, but hey look, that requires an energy input.

3 - Infrastructure. Building a substantial hydrogen infrastructure would be a massive undertaking. Totally doable of course, but it wouldn't happen over night.

4 - If a few thousand psi tank of H were ruptured and ignited with the oxygen in the atmosphere, it'd be a hell of a boom.


As for turbine combos. I have a couple guesses.
1 - Heat. They are damn hot and that's got to go somewhere.
2- Emissions. The heat of combustion has to create some gnarly NOX I would imagine and you can't put highly restrictive cats on the output of a turbine. Or at least not easily as I understand it. They really have to breathe freely.
3 - They are damn loud and there's only so much you can do about that.
4 - Startup procedures for turbines are dirty and require a lot of fuel.

They have a lot going for them though. The turbine would probably only need to be about the size of a large coffee can or so in order to generate enough current to electrically power a mid size car. They're extremely well understood. They can burn a wide variety of fuels, and things like CNG (which we have a lot of in the US) would work fine.

[BADDASSC6]

Originally Posted by SeanPlunk

Forgive my ignorance, but what's the limiting factor? Is it cost, size, or both?

Ben hit the nail on the head. There is effort to find new molecular combinations that will readily combine and release the hydrogen. This would eliminate the need for the crazy tanks and increase the safety of running a hydrogen powered car. The problem is that inevitably there will be some adverse enviromental effect, therefore negating any gains from gasoline.

Gas turbine engines run hotter, but they make SO much power that you can restrict them and still out power anything on the road. The biggest problem is that Turbine engines have a lot of inertia. They don't change power levels quickly. That means that if you are wide out you will be wide out for a while. The same thing happens when it's idle. That means that you will need some kind of resevior. The idea is to have the turbine operating at a constant RPM spinning a generator. The generator powers directly AC motors. There will have to be a battery big enough to drive the car for a short while (seconds) and absorb the power generated by the turbine when it's generating a power excess (minutes). The advantage is that due to the lack of recipricating parts and the high operating temperature (carnot heat cyle) The effieciency of the motor is super high. A gass turbine can reach 45-50% effeciency a normal gas engine is in the 25% range.

You could do it with a high effiecency gas or desiel motor that's designed to operate at a fixed RPM. This is what they did on the Quen Mary II. Making a good street motor you sacrifice a little bit every where to widen out the RPM band as much as possible, but you can gain work out by narrowing out that band.