rx-8_boi02

The new performance figures for the rx-8 hydrogen version.

Performance figures
Power 120 bhp / 89.5 kW @ 7200 rpm
BHP/Liter 91.7
Torque 120 Nm / 88.5 ft lbs @ 5000 rpm
Power to weight ratio N/A
Top Speed N/A
0-60 mph Acceleration N/A

I'll post pics later

rx-8_boi02

Pic 1

sco

Hmm, doesn't sound like much fun to drive. Hopefully more research will result in more power and torque.

peterlemonjello

The nice thing about the hyrdro rx-8 is you can switch to gasoline fuel on the fly if you need the original power.

sco

Good point. Didn't realise that it was dual fuel.

rx-8_boi02

It's makes up what it loses in the performance department

rx-8_boi02

For all who want to see the engine.

rx-8_boi02

Another engine shot

labrat

I have trouble wondering why you'd have a hydrogen internal combustion engine. If hydrogen is to be the fuel, then fuel cells are the preferred medium for energy conversion. That's leaving aside the cost of producing the hydrogen, of course and its lousy energy density. The current method of hydrogen production is by electrolysis of water. That consumes molto electricity, which is OK for countries which produce most of their power from clean nuclear stations like Canada, France and Japan, but lousy for Australia which never had the sense to build nuclear power. We have to rely on burning carbon fuel for our electricity.

It makes little sense burning a greenhouse friendly fuel like hydrogen when the mode of production of the hydrogen is distinctly greenouse unfriendly.

I suspect that much of this sort of stuff is PR hype to boost Mazda's green credentials. Could you make a diesel rotary?

rx-8_boi02

I think this is more of a prototype car because it's gonna be a while before get hydrogen cars here in Australia

Hymee

iTrader: (1)

That is that a turbo I see in the first engine pic !!

Power seems low. A hybrid might be nice.

Rolls-Royce already did. In fact, it was one Rotary compressing into another - i.e. the first was a bigger Rotary that provided some of the compression, and that got fed into a smaller rotary, where further compression took place, and the diesel injected.

There is a diagram around somewhere, don't know if it is hosted on the web somewhere.

Cheers,
Hymee.

IKnowNot'ing

The first hydrogen service station has been built in Sweden, I think.
The good think about these H2 prototype engines is to know that petrol engines can burn a lot of different fuels and therefore might survive beyond the last droplet of black gold. However as Labat said, fuel cells are probably the way to go to transform H2 into motion, not petrol engines.
Another point : did you see that huge H2 tank. It goes in the boot so bye-bye luggage capacity.
And the main point Labat raised is the fact that there is little point in offsetting the fuel consumption and related emissions to the nearest fossil fuel power plant. But there, it looks like they're working on clean ways to make H2 (sun,...).
By the way, I'm in favour of nuclear power until we find something better.

rx-8_boi02

They made it to reduce the amount of carbon dioxide which was causes the greenhouse effect so even if it was low in power it is good for the Earth

rpm_pwr

Labrat,
It's only ever intended as a middle ground car. Something to use while the hydrogen infrastructure is still in it's infancy. So you can switch to petrol if you can't find any hydrogen around. The dual fuel setup obviously hurts power, BMW have a H2 only engine that makes as much power as the petrol version did. In a 4.4 litre V8 no less!

Incidentally, BMW had the first H2 service station in Munich. You have to stand behind a huge barrier while robots refill your car from a safe distance!

labrat

rx-8_boi02 misses my point. There's no point in burning a greenhouse friendly fuel in your car if you have to use a greenhouse unfriendly method to produce it (i.e., coal-burning power stations). Because of the inefficiencies in electricity production, transmission, and the electrolysis process, it ends up costing you lots more in energy to get the hydrogen to the car (and producing more CO2) than otherwise would be the case in using petrol or diesel directly.

The hydrogen fuel thing is part of a massive PR exercise by the car companies to enhance or establish their green image. It's meant to buy them time.

Hydrogen isn't a good choice for passenger cars because it isn't energy dense - it takes up a lot of room. Sorry, but I have to introduce some science, but I promise it won't hurt.

The combustion of hydrogen to produce energy can be written as:

H2 + [0] <-> H2O (-285.8 kJ/mol)

That means that for every mole of hydrogen (or 2 grams of hydrogen) you get 285.8 kJ of energy. Turn this reaction around (the two-way arrows indicate it's reversible), and this is how much energy you have to put into 18 grams of water to produce 2 grams of hydrogen. In science, there is no such thing as a free lunch. Concerning energy density, this 2 grams of hydrogen occupies approximately 22.4L at ambient temperature and air pressure. Unlike LPG, you can't liquify hydrogen at normal temperatures. Hydrogen only liquifies at a few degrees above absolute zero. So you have to compress it as high as you dare to carry enough fuel around. This is not a trivial exercise. Not only do you have to introduce extreme safety measures during filling, the material science in long-term storage and transfer of hydrogen is not trivial. Hydrogen embrittlement of metals is well known.

OK, now that you've got your highly expensive hydrogen into your car, are you going to burn it in a notoriously inefficient device as an internal combustion engine, or go to the much more efficient fuel cell, whereby the energy from the above reaction is extracted as electricity to drive electric motors? Seems like a no-brainer doesn't it, only fuel cell membrane technology is still a few years off before being commercially viable. So why are the car manufacturers messing around with hydrogen in internal combustion motors? Brand management - keeping governments and consumers on side until the fuel cell car becomes a reality.

My preference for an interim technology would be common rail diesel engines. This is a much better bet than the petrol/electric hybrid Toyota technology. It offers nearly as good fuel efficiency, and it is much better suited for passenger cars as you don't require expensive and space-consuming storage batteries. On the downside, the petrol/electric sounds environmentally sexier. And that may be thing that counts in the end.

dbb

My preference would be to turn the entire car into something with quantum entanglement properties, and we would teleport down the road a few millimetres at a time.

Car crashes would be interesting though ...

Hymee

iTrader: (1)

Post of the day, Labrat. Any links to the common rail diesels? (I'm lazy )

Cheers,
Hymee.

Hymee

iTrader: (1)

OK - Not too lazy...

http://www.dieselforum.org/factsheet/commonrail.html

In laymans terms, the equivalent of electronic injection for diesels, at very high rail pressure.

Cheers,
Hymee.

rpm_pwr

Out of interest, most industrial hydrogen is made from fossil fuels, specifically natural gas not by electrolysis. But using massive amounts of energy in the compression process is pretty unavoidable I guess.

dbb

Further trivia : there is more hydrogen already in a litre of petrol than there is in a litre of liquid hydrogen because petrol is denser by more than it's hydogen mole fraction.

labrat

Your comment hit the nail on the head, dbb. I would also imagine that getting hydrogen from fossil fuels is energy intensive as well. My crystal ball shows that by the year 2020, we'll be driving cars powered by fuel cells burning methanol, which is a liquid, only contains one carbon, and can be made easily from natural gas. Unfortunately, we'll probably also have to get a permit from the Department of the Environment to start up our RX-8's at classic car shows.

Gomez

*******CAUTION, THREAD HIJACK, CAUTION*******

Don't care, did anyone notice how good the car looks in white?!

YOWZA......!

dbb

Or perhaps Ethanol or Propane? They also have (reasonably) good energy density comparisons.

Anyway, oil production is currently peaking, and will start to dwindle in the near future. Meanwhile, China and India and adding more and more cars to their domestic markets. And Americans continue to purchase more and more SUVs. This will lead us inevitably to oil/resource wars in the next 15 years or so, and we won't be around to worry about what we put in our cars.

rotarenvy

NO IT DOSN'T LOOK GOOD IN WHITE! it sucks, all white cars do!

you have been watching way to much B&W TV Gomez :p

rotarenvy

anyone notice the port profiles on the motor? very large area and looks like the port closes early (short intake duration). very funny shape that looks hand carved too!