Hydrogen BMW. No, not Fuel Cell. Just Hydrogen.

SirNitram · Post by **SirNitram** » 2006-09-08 03:24pm

The car is familiar - but what's that in the boot? Last week, Auto Express put Mazda's hydrogen-powered RX-8 coupé to the test - and now, BMW's 7-Series appears set to follow in the Japanese machine's wheel tracks.

A concept version of the German firm's zero-emission CleanEnergy car has already debuted, but our spies spotted this production variant being worked on and tested in Germany.

The model's huge hydrogen tank fills the vast load area, and is the tell-tale sign that this is no ordinary 7. Under the bonnet, the clever V12 engine is able to run on both petrol and hydrogen, and switches automatically between tanks when one or other hits empty. This powerplant is a development of the 231bhp 6.0-litre 12-cylinder unveiled at the 2003 Frankfurt Motor Show.

BMW has committed to delivering the first roadgoing hydrogen versions within the existing 7-Series' lifespan, so they are expected to go on sale in 2008. Initial examples are likely to be aimed at small fleets, which will provide feedback to assist the company in its development of the technology.

CaptainChewbacca · Post by **CaptainChewbacca** » 2006-09-08 03:33pm

I may be missing something, but isn't a car with a tank of just hydrogen more dangerous than a car with gasoline?

FedRebel · Post by **FedRebel** » 2006-09-08 03:42pm

CaptainChewbacca wrote:I may be missing something, but isn't a car with a tank of just hydrogen more dangerous than a car with gasoline?

No studies have shown that hydrogen fuel is just as stable as gas.

On that note, why wait for the Beemer?

http://www.hydrogennow.org/Facts/Theautomobile.htm

http://www.hydrogenvehiclesystems.com/index.php

Isolder74 · Post by **Isolder74** » 2006-09-08 03:57pm

CaptainChewbacca wrote:I may be missing something, but isn't a car with a tank of just hydrogen more dangerous than a car with gasoline?

Ah, yes the Hindenburg rears her ugly head once again. Say Hydrogen and all anyong can think of is kaboom, despite there being other fuel that burn hotter, Gasoline, or are more explosive, gasoline, under the right conditions.

We can build a gas take that is relatively safe to ues and operate, we can do the same for Hydrogen.

Nephtys · Post by **Nephtys** » 2006-09-08 04:21pm

A pity hydrogen's pretty bad as it is for cars. To produce hydrogen for fuel purposes, the electricity input isn't a particularly good improvement over fossil fuels, considering the power is generally provided by other fossil fuel.

Post by **Mr Bean** » 2006-09-08 04:27pm

Nephtys wrote:A pity hydrogen's pretty bad as it is for cars. To produce hydrogen for fuel purposes, the electricity input isn't a particularly good improvement over fossil fuels, considering the power is generally provided by other fossil fuel.

Which is why there must be a fission reactor in every pot, and a silo in every backyard! Onwards towards our glorius, fossil fuel free future!

Seriously however, Nuke power is the way to go for power generationf or hydrogen seperation. And once we put out collective minds to it, we must likley would improve the efficence of the proccess to make it even more attractive.

Lost Soal · Post by **Lost Soal** » 2006-09-08 05:16pm

Honda have been working on a Hydrogen powered car for a while and are quite a ways through the testing phase.
Mind saying that, there doing the testing on an island which has rain virtually every day and a hydroelectric plant which doesn't have any other towns or cities to power.

Not something you'll generally find

aerius · Post by **aerius** » 2006-09-08 05:27pm

Well that's odd, a 6.0L V-12 and it only makes 231 horsepower, that's literally twice the size of the engine in my car and it only makes 60 more horsepower, and the engine in my car ain't exactly a high output motor.

Burak Gazan · Post by **Burak Gazan** » 2006-09-08 07:21pm

It surely is, considering the 3.0 litre powerplant in the BMW M Roadster develops 330 hp on an inline -6

Is there something about the engineering required for a hydrogen fueled powerplant that kills the horsepower -- it does mention the engine is a dual-fuel system, maybe that has something to do with it

Lord of the Abyss · Post by **Lord of the Abyss** » 2006-09-08 11:43pm

CaptainChewbacca wrote:I may be missing something, but isn't a car with a tank of just hydrogen more dangerous than a car with gasoline?

Nope; hydrogen is very light, and the heat and combustion products from a hydrogen fire tend to go straight up very fast. Gasoline OTOH is much heavier than air, and will cheerfully form pools on the ground - which is bad if it ignites and it's under you. Unless the hydrogen tank is right underneath you, a hydrogen fire will be about as safe as an out of control fire can get. That's one reason why two thirds of the Hindenberg passengers survived, instead of frying.

nickolay1 · Post by **nickolay1** » 2006-09-09 12:35am

Burak Gazan wrote:Is there something about the engineering required for a hydrogen fueled powerplant that kills the horsepower -- it does mention the engine is a dual-fuel system, maybe that has something to do with it

This is also likely due to the the relatively low energy density of the fuel. Much more hydrogen must be burned compared to gasoline to release an equivalent quantity of energy.

aerius · Post by **aerius** » 2006-09-09 11:03am

nickolay1 wrote:This is also likely due to the the relatively low energy density of the fuel. Much more hydrogen must be burned compared to gasoline to release an equivalent quantity of energy.

It's not the energy density, nitromethane has about 1/4 the energy density of gasoline yet the engines in nitro funny cars make several times more power than their gasoline burning counterparts in pro mod.

Looking around the web reveals that it's emissions related. Burning hydrogen at the stoichiometric ratio would give roughly the same power as gasoline depending on how the fuel's metered, but that results in very high combustion temperatures and NOX emissions among other issues. So they lean out the ratio to about half of stoichiometric which fixes those issues but kills the power.