It is always difficult to discuss without any figures - so I hope I can help with this post
Some figures to think about (disclaimer: out of memory so they are not 100% accurate but anyways)
When using hydrogen based on water and electrolyze - hydrogen must be considered as an energy carrier, not an energy source,
because...
The energy produced by using hydrogen withn a fuel cell is theoretical equal to the energy used for the electrolyse.
Why ?
If the fuel cell would produce more energy than used by electrolyze, then we should just recycle the water produced from the fuel cell back to electrolyze and only use a fraction of the energy produced by the fuel cell to make hydrogen out of the recycled water, agian and again and again...
In my (danish) native language it is called a machine of eternity.
So we will theoretical get as much energy out as used for electrolyze.
In praxis efficiency will come in. The fuel cell has an efficiency in the range 55-80% depending on technology, temperatures etc.
Plants for electrolyze has an efficiency below 75%.
So in best case today for every 1 kWh you use for electrolyze you will have not more than 0.6kWh to be used for your electrical engines to move your care.
A more realistic guess is maybe 50% in total efficiency.
1 kg hydrogen at atmospheric pressure fills 12500 liter (or approx 3200 gallons). 1 kg hydrogen gives about 11.8 MJ (or 33 kWh) in a fuel cell.
1 kg hydrogen production takes about 20 MJ(or 55 kWh)...
So it is more than crazy to carry batteries in a car for hydrogen production instead of just powering the electrical wheel engines.
For comparison reasons:
1 kg gasoline gives about 45 MJ 1 kg diesel gives about45 MJ.
With an efficiency of about 33% for a traditional modern diesel/gasoline engine 1 kg fuel gives about 15 MJ.
So 100 kg gasoline equals roughly to 100 kg hydrogen(for fuel cell use) which fills 1.250.000 liter/1 atmosphere or 4166 liters at 300 bar I guess.
Looking forward to see the gas/hydrogen stations along the highway. And it also costs lost of energy to compress the hydrogen...
If we will carry it as water you carry 1 oxygen atom for every two hydrogen atoms - So the equivalent of 100 kg hydrogen is 1700kg water... which fills less than the half of the hydrogen gases...
So there are some problems to be solved - so to say:-)
The positive thing is no CO2 and pollution - which may be be why we ought to do it.
Jens @ Denmark Disclaimer: positive about saving energy and minimize pollution
Some figures (disclaimer: out of memory so they are not 100% accurate but anyways)
When using hydrogen based on water and electrolyse - hydrogen must be consideres as an energy carrier, not an energy source, because...
The energy produced by using hydrogen withn a fuel cell is theoretical equal to the energy used for the electrolyse.
Why ?
If the fuel cell would produce more energy than used by electrolyse, then we should just recycle the water produced from the fuel cell back to electrolyse and only use a fraction of the energy produced by the fuel cell to maked hydrogen out of the recycled water, agian and again and again... In my (danish) naitive language it is called a mechine of eterny.
So we will theoretical get as much energy out as used for electrolyse.
In praxis effeciency will come in.
The fuel cell has an efficeency in the range 55-80% depending on technology, temperatures etc.
Plants for electrolyse has an effeciency below 75%.
So in best case today for every 1 kWh you use for electrolyse you will have not more than 0.6kWh to be used for your electrical engines to move your care.
A more realistic guess is maybe 50% in total efficiency.
1 kg hydrogen at atsmopheric pressure fill2 12500 liter (or approx 3200 gallons).
1 kg hydrogen gives about 11.8 MJ (or 33 kWh) in a fuel cell.
1 kh hydrogen production takes about 20 MJ(or 55 kWh)
So it is more than crazy to carry batteries in a car for hydrogen production instead of just powering the electrical wheel engines.
For comparison reasons
1 kg gasoline gives about 45 MJ
1 kg diesel gives about45 MJ
With an efficieny of about 33% for a traditional modern diesel/gasolin engine 1 kg fuel gives about 15 MJ.
So 100 kg gasoline equals roughly to 100 kg hydrogen which fills 1.250.000 liter/1 atmosphere or 4166 liters at 300 bar I guess - if we have very high efficient fuel cells.
Looking forward to see the gas/hydrogen stations along the highway. NAd it also costs lost of energy to compress the hydrogen...
If we will carry it as water you carry 1 oxygen for every two hydrogen atoms - So the equvivalent of 100 kg hydrogen is 1700kg water... which fills less than the half of the hydrogen gass...
So there are some problems to be solved - so to say:-)
The positive thing is no CO2 and pollution - which may be be why we ought to do it.
Jens @ Denmark
Disclaimer: positive about energy savin
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It is always difficult to discuss without any figures - so I hope I can help with this post
Some figures to think about (disclaimer: out of memory so they are not 100% accurate but anyways)
When using hydrogen based on water and electrolyze - hydrogen must be considered as an energy carrier, not an energy source,
because ...
The energy produced by using hydrogen withn a fuel cell is theoretical equal to the energy used for the electrolyse.
Why ?
If the fuel cell would produce more energy than used by electrolyze, then we should just recycle the water produced from the fuel cell back to electrolyze and only use a fraction of the energy produced by the fuel cell to make hydrogen out of the recycled water, agian and again and again ...
In my (danish) native language it is called a machine of eternity.
So we will theoretical get as much energy out as used for electrolyze.
In praxis efficiency will come in. The fuel cell has an efficiency in the range 55-80% depending on technology, temperatures etc.
Plants for electrolyze has an efficiency below 75%.
So in best case today for every 1 kWh you use for electrolyze you will have not more than 0.6kWh to be used for your electrical engines to move your care.
A more realistic guess is maybe 50% in total efficiency.
1 kg hydrogen at atmospheric pressure fills 12500 liter (or approx 3200 gallons). 1 kg hydrogen gives about 11.8 MJ (or 33 kWh) in a fuel cell. ...
1 kg hydrogen production takes about 20 MJ(or 55 kWh)
So it is more than crazy to carry batteries in a car for hydrogen production instead of just powering the electrical wheel engines.
For comparison reasons:
1 kg gasoline gives about 45 MJ 1 kg diesel gives about45 MJ.
With an efficiency of about 33% for a traditional modern diesel/gasoline engine 1 kg fuel gives about 15 MJ.
So 100 kg gasoline equals roughly to 100 kg hydrogen(for fuel cell use) which fills 1.250.000 liter/1 atmosphere or 4166 liters at 300 bar I guess.
Looking forward to see the gas/hydrogen stations along the highway. And it also costs lost of energy to compress the hydrogen...
If we will carry it as water you carry 1 oxygen atom for every two hydrogen atoms - So the equivalent of 100 kg hydrogen is 1700kg water... which fills less than the half of the hydrogen gases...
So there are some problems to be solved - so to say :-)
The positive thing is no CO2 and pollution - which may be be why we ought to do it.
Jens @ Denmark Disclaimer: positive about saving energy and minimize pollution
Some figures (disclaimer: out of memory so they are not 100% accurate but anyways) When using hydrogen based on water and electrolyse - hydrogen must be consideres as an energy carrier, not an energy source, because ...
The energy produced by using hydrogen withn a fuel cell is theoretical equal to the energy used for the electrolyse.
Why ?
If the fuel cell would produce more energy than used by electrolyse, then we should just recycle the water produced from the fuel cell back to electrolyse and only use a fraction of the energy produced by the fuel cell to maked hydrogen out of the recycled water, agian and again and again ... In my (danish) naitive language it is called a mechine of eterny.
So we will theoretical get as much energy out as used for electrolyse.
In praxis effeciency will come in.
The fuel cell has an efficeency in the range 55-80% depending on technology, temperatures etc.
Plants for electrolyse has an effeciency below 75%.
So in best case today for every 1 kWh you use for electrolyse you will have not more than 0.6kWh to be used for your electrical engines to move your care.
A more realistic guess is maybe 50% in total efficiency.
1 kg hydrogen at atsmopheric pressure fill2 12500 liter (or approx 3200 gallons).
1 kg hydrogen gives about 11.8 MJ (or 33 kWh) in a fuel cell.
1 kh hydrogen production takes about 20 MJ(or 55 kWh)
So it is more than crazy to carry batteries in a car for hydrogen production instead of just powering the electrical wheel engines.
For comparison reasons
1 kg gasoline gives about 45 MJ
1 kg diesel gives about45 MJ
With an efficieny of about 33% for a traditional modern diesel/gasolin engine 1 kg fuel gives about 15 MJ.
So 100 kg gasoline equals roughly to 100 kg hydrogen which fills 1.250.000 liter/1 atmosphere or 4166 liters at 300 bar I guess - if we have very high efficient fuel cells.
Looking forward to see the gas/hydrogen stations along the highway. NAd it also costs lost of energy to compress the hydrogen...
If we will carry it as water you carry 1 oxygen for every two hydrogen atoms - So the equvivalent of 100 kg hydrogen is 1700kg water... which fills less than the half of the hydrogen gass...
So there are some problems to be solved - so to say :-)
The positive thing is no CO2 and pollution - which may be be why we ought to do it.
Jens @ Denmark
Disclaimer: positive about energy savin