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Hydrogen engine

  1. Feb 4, 2014 #1
    Hello PFs,

    (It should be eco-friendly project)
    I am working on ICE using hydrogen fuel. My very first step is to produce hydrogen from water that i have achieved by electrolysis.(hope to see another method as i have heard one to produce from sunlight) I am using this hydrogen and oxygen directly into engine along with air, about 33% of hydrogen in cylinder and rest oxygen and air. This i believe is producing NOx which i dont want. Well i have to work hard i know, but stuck in the first step as whether to line the separated directly into the cylinder or go for purifying H2. If anyone has already done some research in this field, kindly guide.

  2. jcsd
  3. Feb 5, 2014 #2


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    If you are producing both H2 and O2 by electrolysis of water then it is important to isolate them and to store them separately so as to avoid the hazard of an explosion. They will be in the correct ratio for combustion, but you will have to meter them so as to keep the ratio correct, and you will need two tanks.

    The O2 will be heavier than the H2. So you might consider selling your O2 locally, that way you do not have to cart it around with you. You then only need one tank on the vehicle. You can burn your pure H2 with air in the same way that LPG is used.
  4. Feb 5, 2014 #3
    Thanks for your reply baluncore.
    but if i mix H2 with air, wont it produce NOx?
  5. Feb 5, 2014 #4
    and if you are suggesting to separate hydrogen and oxygen from water on ground and not in automobile. Maybe electrolysis is not perfect method for separation. Can you suggest any? And i have read a year ago about separation using sunlight as source and titania as catalyst. I would like to know more about this technique. Correct me if i am wrong.
  6. Feb 5, 2014 #5


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    Generating hydrogen and oxygen on the vehicle will be very inefficient. An ICE is very inefficient compared to electric motors. You would be better using electric current to charge a battery for use with electric motors. Then you have the added efficiency of regenerative braking and many alternative sources of charge.

    Yes there will be some NOx produced but you can control it like is done in LPG / CNG powered vehicles.

    Maybe you should study all possible ways of storing energy efficiently, and safely.
  7. Feb 7, 2014 #6
    can you suggest me any alternate method to produce hydrogen rather then electrolysis. And what pressure will be safe to store hydrogen?
  8. Feb 7, 2014 #7


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    Where do you want to use your hydrogen? What source materials do you have from which you might extract hydrogen. Water, methane and many others. Environment and economy are important.

    To get any energy out you must first put some in. What source of energy do you have to perform the energetic chemistry necessary to separate the hydrogen.

    The more pressure you use to store your hydrogen, the more energy you put into compressing it. PF and I do not recommend it for beginners but cryogenic liquid hydrogen is quite possible. http://en.wikipedia.org/wiki/Space_Shuttle_Main_Engine

    We have managed to avoid inefficient hydrogen fuelled ICEs in vehicles because electric power is cleaner and much more efficient. Performance of electric vehicles is way better than hydrogen fuelled ICEs because the generator needed for regenerative braking is the same unit as the motor used for acceleration. If you have hydrogen then it would be better used for generation of electricity by reverse electrolysis which is a fuel cell, than to be burned in an ICE.
  9. Feb 14, 2014 #8
    source i would like to take should be surplus. Here i would like to extract hydrogen from water.

    Obviously the energy will be greater, to extract hydrogen from water, in electrolysis. Hence i would like to use solar to extract hydrogen.

    thanks for the article but i am not going for this right now.

    I was more thinking of just producing H2 on the vehicle. BTW your suggestion sounds good of using it as fuel cell just like batteries. But why not lead acid batteries then? Produce energy, convert it into electricity and charge batteries. This will be atleast safe.
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