Converting gas engine to hydrogen

[Laiky]

A couple of guys in our machinists group has been playing around with hydrogen generators and have only improved their mileage on a Toyota Corolla by only 2-3mpg. The drain on the electrical system offsets any improvements from the conversion. The principal involved is to generate sufficient hydrogen via electrolysis and they typically are running 30-40 amps for the hydrogen generator. I personally don't think this is the way to go. Buy a diesel instead.

do you know which one they are using? a friend is working on one, i say theoretically impossible, i'm surprised they saw 2-3 mpg

[burninbriar]

I have the same feeling about the on board generators. It takes energy to make energy, so I don't see how you can benefit from robbing energy for the engine to produce energy for the engine. I've also heard of a plan to use wind turbines mounted on the vehicle to produce the electricity but again you are increasing the drag on the vehicle counteracting any energy gain.

[Bodybagger]

First law of thermodynamics: there is no free lunch. You can never get more energy out than you put in. The best you can hope for is to break even.

Second law of thermodynamics: You CAN'T break even. No process is 100% efficent because heat needs work just to move. Every step you add will decrease the overall efficiency.

And as far as using hydrogen by itself as an internal combustion fuel, it just detonates when ignited. The octane rating of hydrogen is "very low."

[MAC702]

I have the same feeling about the on board generators. It takes energy to make energy, so I don't see how you can benefit from robbing energy for the engine to produce energy for the engine....

It COULD give you a small gain, IF the engine was wasting energy while you were idling or cruising without acceleration. BUT, no way do I see it worthwhile.

[WyoRoy]

Quote by Bodybagger:
And as far as using hydrogen by itself as an internal combustion fuel, it just detonates when ignited. The octane rating of hydrogen is "very low."

Thus the reason for fuel cell/elec. motor technology. Screw the octane and the internal combustion engine it rode in on. Reverse engineering to run an internal combustion engine on hydrogen would be counter-productive when the technology is closing in on commercial success for fuel cell vehicles that will power a vehicle more efficiently without the Rube Goldberg internal combustion engine in the equation.

[Laiky]

I've been reading a really good book on Hydrogen. I believe the title is "Hydrogen, hot stuff cool science" It's written as a story but hits many technical points. I just read the chapter on hydrogen as a internal combustion engine fuel. It is possible to use hydrogen but the sucess they have achieved includes direct injection to deal with backfiring and water injection to stop detonation. I think you would be able to convert with water injection only but it doesn't go into extream depth. The nice thing about the book is that it references many articles and sites if you want to investigate further. I'll bring the book to work with me and get the references for the ICE hydrogen stuff and post them.

[jweller]

A little off the subject, but have you considered building and tuning it to run on e85. not flex. e85 all the time. E85 has an octane rating of around 100 - 105 and has a lower energy density than gasoline, meaning you need about 30% more fuel. you can safely run something like 13:1 CRs with it though. and it makes a ton more power when you are set up properly.

If your set on hydrogen, then just act like my wife, and ignore me. If you're interested in alternative fuels, check it out.

[Laiky]

http://www1.eere.energy.gov/hydrogen...fs/fcm03r0.pdf

took a while to find, the link was old. Haven't read it yet

[burninbriar]

Thanks a lot for that link. I read about half of it so far, getting tired now, I'll finish it later.

[Dmaxer]

My truck engine finally took a dump on me the other day, I think it spun a bearing or something. It started knocking really bad from what seems like the lower end (I have bad hearing) and its loosing oil pressure pretty bad.
Anyway, since I have to dismantle it if I choose to go the rout of fixing, and I don't use the truck that much, I thought I might try a hydrogen conversion as an experiment. I believe its Greenland where they are using hydrogen on a regular basis dew to the relatively cheap electricity from their hot springs to produce the hydrogen.

Any help would be appreciated. So far what I can gather is that titanium valves and seats are needed, don't know if thats true or not. As for a carburetor, I've heard that a propane carburetor will work, again I don't know the validity of that and if so, what modifications might be needed.

Any thoughts?
The engine is a 502 GM. I also haven't checked on the availability of hydrogen in my area yet.

Getting in on this late but thought I'd add: without plentiful energy (from excess hydrogen production?) to power the pumps and cryogenic processes to compress the hydrogen to a liquid at about 10,000 psi (700 bar), it is unlikely that hydrogen will be available anytime soon in a useful form for automotive purposes. Not to mention the strength required and therefore the weight of a portable tank to contain that kind of pressure for use in an automobile. Not to mention the risk of hydrogen embrittlement of steel lines for moving hydrogen. These problems can be overcome, but not cheaply and not today. See, if you haven't already, http://en.wikipedia.org/wiki/Hydrogen_economy for an in-depth discussion. BTW it is Iceland that is using excess geothermal output to electrically split H20 into H and 02 and compress it for fuel purposes.