Even if electric vehicles can really overcome their issues, I'm confident that my ideal alternative fuel vehicle will remain a hydrogen one. What I want is a hydrogen-fuelled (or even multi-fuelled), combined cycle, gas turbine engine coupled with an IVT comprising of a rotary, variable displacement, hydraulic pump and a rotary, hydraulic motor. Build me that and I'll buy it...  Visiting from DISCO3.CO.UK
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 MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

Eh?  Visiting from DISCO3.CO.UK
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I don't think that either a gas turbine or hydraulic motor are very eco friendly, from an MPG point of view. Lots of grunt, but lots of fuel to provide that power If your going to do that then you might as well stick with a hurdy great V8 and run it on 5 star Vodka Added bonus that if it was to breakdown in the middle of nowhere you wouldn't have far to go to find a drink, and you wouldn't have a care in the world either  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

A gas turbine can be very efficient as part of a combined cycle (the thermal efficiency is better than that of a piston engine, with the waste heat being easily captured from the exhaust) - hence their use as powerplants. Above all, they have a much higher power to weight ratio, and are capaple of handling various and low quality fuels etc. - it'd be easier to produce a hydrogen powered turbine than a piston engine (which would have to be made bigger and heavier to cope with hydrogen).

The IVT would allow it to run at a constant speed, removing issues of poor response and improving efficiency a lower speeds. It's easy to see a gas turbine as a big, fuel guzzling machine fitted to aeroplanes, but they can be made into tiny little thing that can sit in your hand and produce a few hp. I believe Land Rover and Jaguar are planning an extended range hybrid with a turbine engine.

Electricity for electric vehicles is available for free as an incentive (or, in truth, I guess it's also factored into the purchase price) but I can't see it staying that way, and when at higher speeds, the efficiency of an electric vehicle drops dramatically. Electric could be used for city drivers, and hydrogen for longer distances and country dwellers.

Not sure why a hydraulic motor would be inefficient. As a piston type pump (with radial cylinders) in reverse, there would be very little potential for any losses, unlike a torque converter, for instance, which is not dissimilar in principle.

Vodka idea could work...just get the whole country drunk so they can't drive anywhere. Emissions crisis solved!

 Visiting from DISCO3.CO.UK
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Ok, so we are talking of a turbine the size of a shoe box then, rather than something the size of the engine that's in the car.
But Hydraulic motor? to only things they drive is slow moving machinery that needs variable speed input for precise control, virtually every thing that I can think of that needs grunt uses electric motors. Large dump tucks, ships, immediately it gets big they stick an electric motor in it. The Nazi's where building a super tank, it was somewhere along the lines of 4 times bigger than a Tiger, and that was electric powered. All the trains are electric powered at the wheels now a days, surely if hydraulic was better the someone would be using it by now?

But you could use the turbine to power an alternator and end up with a genset that would fit in a case

I think that I've just sussed what an IVT is, is it an Infinitely Variable Transmission? Bloody farmers, why can they call it a CVT like the rest of the world.
Anyway this would be totally unnecessary, as hydraulic power is already variable to the n'th degree, why have 2 variable systems in the same power train?

How about a Vodka powered turbine genset? light weight, and small so you could have a bigger fuel tank, just in case you got thirsty

Hydrogen is all well and good, but it is very costly to make, and until they can invent a way to produce it cheaply I fear that it's a non starter. They were messing around with hydrogen powered cars in the 70's. You can run a std engine on the stuff, but the problems with gas production soon knocked that one on the head  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

Quote:

I think that I've just sussed what an IVT is, is it an Infinitely Variable Transmission? Bloody farmers, why can they call it a CVT like the rest of the world. Anyway this would be totally unnecessary, as hydraulic power is already variable to the n'th degree, why have 2 variable systems in the same power train?

The difference with an IVT over a CVT is that the gearing runs from zero, so no clutch/fluid coupling required.

I think I've confused you slightly. The hydraulic motor is part of the IVT itself. The engine (of whichever variety) turns a radial cylinder block of the pump. The pistons are attatched via bearings to a round plate-type bracket which is moved perpendicular to the axis of rotation, varying the displacement and thus the amount of fluid pumped. When in the central position, no fluid is pumped making the gear zero. The on the output side, the fluid is pumped through the hydraulic motor of similar, but fixed displacement, design - the more fluid pumped, the faster the output shaft must turn. By shifting the pistons across the axis, reverse gearing can even be achieved.

A hydraulic transmission has the weight advantage over electric to deliver the same power and is able to provide a true constant torque drive, which electric can't.

Naturally, producing hydrogen is an issue, but then no alternative fuel is without it's issues and with a gas turbine, it could basically be made to run on whatever fuel is shoved in it.  Visiting from DISCO3.CO.UK
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5 star Vodka

IVT is a wobble pump but the drive plate is flat and the pump is slewed / twisted to vari how hard it pumps? sneaky

And yes a hydraulic motor is a lot lighter for the power, but the feed is a lot bigger (hoses) and cost a lot more than cable. And there is the added bonus that If your car is electric it does have the potential to power your home in a crisis, or your tint ten in a field........ Don't think they have invented the hydraulic kettle yet , and now someone is going to post a link for hydraulic kettles  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

Quote:

IVT is a wobble pump but the drive plate is flat and the pump is slewed / twisted to vari how hard it pumps? sneaky

Not quite, that's pehaps a more common version - the swashplate. I'm thinking of a radial design, for ease of adjustment and greater strength. The intention was that this only replaces the transmission - and a conventional drivetrain remains to provide better off, and indeed on, road ability. Doesn't save weight, but it's more suitable for a LR, where weight is high anyway, and a fair amount is needed for stable towing.

Hydraulic kettle...maybe not, but the design would not be without a conventional alternator.  Visiting from DISCO3.CO.UK
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 Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

Neat. That's using the same principles of another version I've been thinking of - a diff, with one output shaft controlled by a serviceable braking system. Can't quite get my head around how his manages to not require equal work to be applied to the controll shafts though!  Visiting from DISCO3.CO.UK
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He is only applying power to the bottom shaft, all the torque is transferred through the gearbox via both shafts, but each one is capable of handling all the power on its' own. so if the bottom shaft isn't turning everything is going through the top, the more the bottom shaft is turned by the smaller motor the slower the top shaft goes and the slower the output. When the lower shaft exceeds the speed of the top shaft the output goes in to reverse. It is a brilliant bit of kit, I hope that he gets it in to production, as it is effectively an automatic transmission, without any friction material, so it should stay one hell of a lot cooler and will give you all the power of the engine,and no torque converter

Knowing what goes on inside an automatic gearbox, I'm surprised that manage to get any power to the wheels as it's a line of slipping clutches driven by some whipped up oil in the torque converter. Whoever came up with that idea must have been considered a mad scientist But it does work, I get the feeling that it's not all that efficient due to all the power that is turned in to heat. That D drive looks like it could be near to 100% efficient  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

Quote:

But it does work, I get the feeling that it's not all that efficient due to all the power that is turned in to heat.

Exactly. ISTR, Disco Mikey found something like 80hp was lost through through his D3's drivetrain (with his old, poorly box mind) when it went on the dyno...  Visiting from DISCO3.CO.UK
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that's half the total power that I've got  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

I would think and hope that with the transmission in a better state that would be a good deal better at least, but the losses are certainly not insignificant. Visiting from DISCO3.CO.UK
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