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Thread: Is Hydrogen gas a biofuel?

  1. #1
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    Is Hydrogen gas a biofuel?

    Hello and thanks in advance,

    I have a hydrogen question and nowhere to ask...

    I hope this is the right place.

    I am trying to figure out if it is possible to:
    • make distilled water from sea-salt water
    • split that water to produce hydrogen gas (for various uses - fuel is one of them)
    • how to make it commercially viable
    • if to make it commercially viable, alternative energy devices (like solar panels and wind towers) are needed to power the equipment

    Where do I find all this information? Is there a feasibility study completed somewhere that i can my hands on? I have searched the web a bit but found nothing usable


    Thanks for your help !

  2. #2
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    Re: Is Hydrogen gas a biofuel?

    I have a hydrogen question and nowhere to ask...

    I hope this is the right place.

    I am trying to figure out if it is possible to:
    • make distilled water from sea-salt water
    • split that water to produce hydrogen gas (for various uses - fuel is one of them)
    • how to make it commercially viable
    • if to make it commercially viable, alternative energy devices (like solar panels and wind towers) are needed to power the equipment

    Is it a biofuel? I have never heard of any metabolic process that produces hydrogen. The idea is to burn it as part of more complex molecules. But this is a great place to ask because some people have been to school. And there isn't really anywhere to find the answers because nobody bothers to ask them.

    Yes you can make distilled water from sea water. Rain is exactly that done effortlessly and perfectly viable commercially just collected off your roof. So why would you want to use energy to do it yourself?

    Yes it is very easy to split it into hydrogen gas and oxygen. Any high school chemistry text will show you a picture of the apparatus. And it takes exactly the same amount of electrical power to split as you release when you burn the hydrogen. So why would you want to do it? A typical internal combustion engine gives about 40% of the combustion energy back for a drive train with a 60% loss as heat. So it makes better sense to go straight to an electric motor which has an efficiency around 90 some percent. One thing it can be used for is a hydrogen/oxygen torch for soldering jewelry, burnt as it is produced it does a very nice job but needs a lot of permeable metal filter to prevent blowback.

    As hydrogen is the lightest gas of all it is also the most inefficient to compress and store. LIke you would need a huge high pressure cylinder. Or maybe a million dollar platinum sponge.

    I don't suppose there is any need to discuss commercial viability. Why don't you just make some biodiesel, somebody else has already paid for the feedstock which they will give to you for nothing and it will power a diesel car or furnace or generator or whatever very nicely.

    Sorry to be so short with you- you probably have heard of a non-polluting hydrogen economy or some such. Its one of those things that is theoretically possible and makes people feel good to imagine but is completely impractical because just about anything is a better solution.

  3. #3
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    Re: Is Hydrogen gas a biofuel?

    Hi gsmiley
    Quote Originally Posted by gsmiley View Post
    And it takes exactly the same amount of electrical power to split as you release when you burn the hydrogen.
    No it does not. There is always a loss when you do this type of conversion.


    So why would you want to do it? A typical internal combustion engine gives about 40% of the combustion energy back ...
    It is actually closer to 32%


    So it makes better sense to go straight to an electric motor which has an efficiency around 90 some percent.
    The problem is that currently most cars actually use inefficient internal combustion engines.


    As hydrogen is the lightest gas of all it is also the most inefficient to compress and store.
    Are you sure that hydrogen gas is the most inefficient gas to store and compress and the reason for this is because it is the lightest gas of all?
    I can not find that information on the www anywhere.


    LIke you would need a huge high pressure cylinder. Or maybe a million dollar platinum sponge.
    To do what?


    I don't suppose there is any need to discuss commercial viability.
    Why not?



    Why don't you just make some biodiesel,
    Maybe he does not want to run a diesel engine.



    somebody else has already paid for the feedstock which they will give to you for nothing
    A lot of people are now paying for their WVO.



    and it will power a diesel car or furnace or generator or whatever very nicely.
    It will not run an SI engine



    ... but is completely impractical because just about anything is a better solution.
    Do you mean like a coal fired steam locomotive?
    Last edited by tillyfromparadise; 15th April 2012 at 12:42 AM.

  4. #4
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    Re: Is Hydrogen gas a biofuel?

    Gsmiley,
    You are on the right track, but on the efficiency side of things, here is a quote from Wikipedia on efficiency of Electrolysis
    (comparing the energy to split H2O, with the energy returned when recombined - NOT when burned in a Internal Combustion engine)
    The energy efficiency of water electrolysis varies widely with the numbers cited below on the optimistic side. Some report 50–80%.[13][14][15] These values refer only to the efficiency of converting electrical energy into hydrogen's chemical energy. If one considers simply the electrical energy input to an electrolyser and the enthalpy of combustion of the H2 product, then efficiency of above 90% for simple electrolysers is typical (with platinum catalysts and a PEM). The energy lost in generating the electricity for the electrolyser is not included in this figure. For instance, when considering a power plant that converts the heat of nuclear reactions into hydrogen via electrolysis, the total efficiency may be closer to 30–45%,[16] although the inefficiencies of powerplants in turning heat into electrical energy is not usually included in efficiency, so the former measure of 50–80% efficient is probably a more realistic efficiency.

    By the way, DO NOT try to electrolyse Hydrogen from sea water. While it will produce hydrogen, it will also produce chlorine, which can kill you.

    Regards,
    Tony
    Life is a journey, with problems to solve, lessons to learn, but most of all, experiences to enjoy.

    Current Vehicles in stable:
    '06 Musso Sports Crew Cab. Running on used cooking oil with 5% to 10% misfuel.
    '2014 Toyota Prius (on ULP)


    Previous Vehicles:
    '90 Mazda Capella. (2000 - 2003) My first Fatmobile. Converted to fun on veggie oil with a 2 tank setup. Died when supercharger stuck at max boost for weeks. Stretched head bolts.
    '80 Mercedes 300D. 2 tank conversion [Sold]
    '84 Mercedes 300D. 1 tank, no conversion. Replaced engine with rebuilt OM617A turbodiesel engine. Finally had good power. Donor for current Fatmobile coupe. (body parted out and carcass sold for scrap.)
    '99 Mercedes W202 C250 Turbodiesel (my darling Wife's car)[sold]
    '98 Mercedes W202 C250 Turbodiesel (my car)[sold]
    Parts Car C220 1993 SOLD.
    '85 Mercedes Benz W123 300CD Turbodiesel single tank using 95% used cooking oil and 5% to 10% misfuel (where someone had filled diesel vehicle with petrol).


    Searching the Biofuels Forum using Google
    Adding images and/or documents to your posts


  5. #5
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    Re: Is Hydrogen gas a biofuel?

    http://en.wikipedia.org/wiki/Electrolysis_of_water is the source of the quote above.
    Tony
    Life is a journey, with problems to solve, lessons to learn, but most of all, experiences to enjoy.

    Current Vehicles in stable:
    '06 Musso Sports Crew Cab. Running on used cooking oil with 5% to 10% misfuel.
    '2014 Toyota Prius (on ULP)


    Previous Vehicles:
    '90 Mazda Capella. (2000 - 2003) My first Fatmobile. Converted to fun on veggie oil with a 2 tank setup. Died when supercharger stuck at max boost for weeks. Stretched head bolts.
    '80 Mercedes 300D. 2 tank conversion [Sold]
    '84 Mercedes 300D. 1 tank, no conversion. Replaced engine with rebuilt OM617A turbodiesel engine. Finally had good power. Donor for current Fatmobile coupe. (body parted out and carcass sold for scrap.)
    '99 Mercedes W202 C250 Turbodiesel (my darling Wife's car)[sold]
    '98 Mercedes W202 C250 Turbodiesel (my car)[sold]
    Parts Car C220 1993 SOLD.
    '85 Mercedes Benz W123 300CD Turbodiesel single tank using 95% used cooking oil and 5% to 10% misfuel (where someone had filled diesel vehicle with petrol).


    Searching the Biofuels Forum using Google
    Adding images and/or documents to your posts


  6. #6
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    Re: Is Hydrogen gas a biofuel?

    Using hydrogen is a good way to supplement your cars fuel usage.We biodieselers use the same chemicals (KOH or NAOH either one) as one would use to make distilled water conductive for the electrolysis process.There are a other ways to make hydrogen,why use electricity.You can make it biologically,chemically and electrically.
    Storage doesn't just have to be high pressure cylinders for storage,metal hydrides are used also to store hydrogen as a solid storage medium.You can also have an "on demand system" aswell.

    Cheers
    Pete
    96 Dual Cab Rodeo B100% since Jan 2011

  7. #7
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    Re: Is Hydrogen gas a biofuel?

    Well. Sorry guys I must apologize. I didn't figure heat, wire resistances or anything like that for electrolysis. So its actually worse than my theoretical.

    Paying for oil? Looking at Qantas' CEO the other day it will probably happen sooner than we think, and it isn't going to be easy to compete with subsidies, renewable fuels rebate and carbon tax.

    SI engines? Which are?

    Yes hydrogen is the lightest gas, H2 (diatomic) atomic weight 2. The next is Helium, He atomic wt 4 which is inert and diatomic. And because a standard volume (22.4 litres at sea level and I can'[t remember the temperature freezing I think) has the same number of molecules for any gas, that means the weight in that volume is the atomic weight of the gas molecule expressed in grams. So 22.4 litres H2 at STP has 2 grams which is why it is so good to lift balloons and so lousy for a usable fuel. Look up acetylene but I think the next is methane CH3(biggest fraction of natural gas) 16 grams in the same volume or 8 times the weight of hydrogen. I'm not going to look up the relative BTU's but natural gas is even too difficult for motor fuel as we know it because the only way to pipeline it or worse hold a decent volume of it is liquified at - 160 centigrade venting to the atmosphere. Doable for freight and public transit where you are going all the time but if you leave it sit for a few days it all blows away. Which is why it is more often used room temp. for stationary purposes.
    London has storage tanks everywhere for household use - huge cylinders that slide up and down in iron frameworks with the bottom end open in a pool of water like a caisson.

    Finally as hydrogen as motor fuel. This keeps coming up and I have a standing offer that I will build and supply a beautiful metal hydride or calcium metal or better yet a carbide system that will run a vehicle well enough to con some fool like Joh Bjelke Petersen into thinking he has a free lunch running on water. The downside is only that the recharge for the generator will cost at least tenfold/km over say petrol and you can spend your weekends chipping caustic soda or somesuch crap out of the generator.

    Better to go the electrolysis route in your motor vehicle, running off the alternator you will expend maybe 4 times the energy you recover through recombustion unless you decide to dispense with the motor fuel entirely in which case you can spend your whole life playing around with the thing to no avail. There are uglier hobbies.

  8. #8
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    Re: Is Hydrogen gas a biofuel?

    Hi gsmiley,
    Quote Originally Posted by gsmiley View Post
    SI engines? Which are?
    Spark ignition.



    Yes hydrogen is the lightest gas, H2 (diatomic) atomic weight 2...
    I am not questioning that Hydrogen is the lightest gas, just your statement that this makes Hydrogen the most inefficient and expensive to store.



    I'm not going to look up the relative BTU's but natural gas is even too difficult for motor fuel as we know it because the only way to pipeline it or worse hold a decent volume of it is liquified at - 160 centigrade venting to the atmosphere.
    15 years ago one of the teachers where I worked was using CNG (Compressed Natural Gas) to fuel his car. Natural Gas is not normally liquified when used as a motor fuel in cars.




    Doable for freight and public transit where you are going all the time but if you leave it sit for a few days it all blows away.
    CNG is stored in a big pressure tank in the car and does not blow away after a few days.




    London has storage tanks everywhere for household use - huge cylinders that slide up and down in iron frameworks with the bottom end open in a pool of water like a caisson.
    Those tanks have nothing to do with storing hydrogen. They were originally used to store "Town Gas" which is the gas that is produced when you produce coke. I have no idea what type of gas they store in them now or if they store anything in them at all.

    Last edited by tillyfromparadise; 16th April 2012 at 08:29 AM.

  9. #9
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    Re: Is Hydrogen gas a biofuel?

    gsmiley,
    sorry mate but I have to disagree with you when you say
    [Quote]" but natural gas is even too difficult for motor fuel as we know it because the only way to pipeline it or worse hold a decent volume of it is liquified at - 160 centigrade venting to the atmosphere. Doable for freight and public transit where you are going all the time but if you leave it sit for a few days it all blows away."[End Quote]
    Brisbane's translink buses have been running on CNG for the last couple of years,I don't know if all or some are converted but they do run on CNG.
    I feel a bit dumb for asking but what do you mean by if you leave it sit for a few days will blow away.
    Of course it will blow away if uncontained,did I miss something in your statement cause if didn't make a lot of sense.
    Not trying to be a smart arse just didn't get what your trying to say.

    Cheers
    Pete
    96 Dual Cab Rodeo B100% since Jan 2011

  10. #10
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    Re: Is Hydrogen gas a biofuel?

    Sure compressed hydrogen or natural gas works. My point is that it is impractical and you can figure it out with the following equation:

    PV=nRT where P is pressure V volume, n the number of moles(an atomic wt. of the gas expressed in grams or whatever as long as you use R the gas constant and all the other units correctly. T is degrees Kelvin which is an absolute scale of centigrade degrees where zero is absolute zero, -273 degrees centigrade. So now you can figure it all out. ie 22.4 litres hydrogen(about half a normal fuel tank in size) holds 2 whole grams at standard temperature pressure. At 2 atmospheres you double that to 4 grams. Which won't get you far. 10 atmospheres gives you 20 grams capacity and by the time it holds a 100 grams you are getting toward a fairly heavy and getting dangerous cylinder. Or double the amount by halving the temperature, like say dropping to around -150 centigrade.
    Someone was selling a chicken gas system plan on the internet, a plastic bag that filled the whole rear passenger compartment of his car. Say 1 cubic metre or 1000 litres which is 50 times 22.4 litres approx. means it holds 50x16 grams=800 grams of fuel. A lighter molecule has more available energy because it doesnt' need to be torn apart, so say that is the equivalent of at least a litre of petrol. You want to compress that instead just put a parameter in the equation. And it will NOT blow away but you won't have very much capacity either. I was talking liquified and after a phase change the gas equation is not valid. But hydrogen only liquifies close to absolute zero. So liquified H2 or CH3 gives you a similar range to any liquid fuel BUT even methane it is only liquid at crazy low temperatures and it has to be vented or else you are in danger of levelling a city block if it accidently warms up which it will because you can't hold it at -100 degrees C or thereabouts which is why it works best when the machine is in use full time. So if you want to run a vehicle on gas you automatically choose LP which is heavy enough to be liquid at fairly low pressure and there is an infrastructure already out there.

    I thought the caissons now hold natural gas from the North Sea for household use. If they weren't being used they certainly wouldn't still be covering very expensive real estate. Or do they still make coal gas?
    Last edited by gsmiley; 16th April 2012 at 11:52 PM.

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