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In my research and by asking questions on sites like this. I have learned that why using electricity in water can make hydrogen using the process electrolysis, why isn't it the most effective way? To it get all the hydrogen molecules to break away or only a few can be reached using this method? Or which I think it is, is the fact that it take longer to successful separate all the hydrogen from the water and it in turns uses more energy to do it. Is my theory correct or electrolysis is just not a s way to produce hydrogen as it can not separate all the hydrogen?

Just kind of as a second question. How hot do they water/environment have to be to get the hydrogen to separate?

LostPecti
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    FYI: It takes at least as much energy to separate hydrogen from oxygen as you get by burning hydrogen and oxygen. Hydrogen technology is not useful as a primary source of energy: It's only useful for storing energy. – Solomon Slow Jun 01 '16 at 15:16

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It is perfectly possible to produce hydrogen from electrolysis. It's theoretically simple and easy to understand and remember.

The only reason why it's not used most of the time is that even more efficient methods exist. Electrolysis has a very low efficiency, most of the energy ends up being converted to heat. These days, 95% of the hydrogen is produced by steam reforming. With a metallic (nickel) catalyst and at temperatures of order 1,000 degrees Celsius, methane CH4 (from natural gas or basically any fossil fuels) and water H2O change to carbon monoxide CO and hydrogen H2.

Extra hydrogen is obtained when toxic CO combines with water H2O to create harmless carbon dioxide CO2 and hydrogen H2.

Luboš Motl
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  • When you say most of the energy is converted to heat. So do it turn to hydrogen first then heat or do it convert to heat and only heat? – LostPecti Jun 01 '16 at 13:37
  • If you already had the hydrogen, you could stop the electricity etc. Well, the heat is developed after some hydrogen atoms were liberated, but before others are liberated. ;-) The two processes - the liberation of hydrogen and the production of heat - are simply inseparable if you want a macroscopic amount of hydrogen. And these losses are higher than for the technologies based on the fossil fuels, basically because the H-O bond is stronger than the C-H bond. – Luboš Motl Jun 01 '16 at 14:03
  • You mixed efficiency and energy sources in you answer. Using CH4 reducing agent and sort of energy source for process, which instead generation of electricity used directly in process. Along with other factors it makes process simpler and cheaper. Overall efficiency of electrolysis is 60-70 percent at the moment. – MolbOrg Jun 01 '16 at 22:16
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The interesting thing is that the electrolysis of water to produce hydrogen is a possible way of storing energy when the electricity is produced by renewable energy sources which have a variable output eg wind turbines and solar cells.
There is currently a lot of research being done at the National Renewable Energy Laboratory (NREL) and many other sites around the world.

This schematic shows taken from the Florida Solar Energy Center website shows the various methods which are and potentially can be used to produce hydrogen.

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and at that website you will see that at present the cost of production of hydrogen using renewable fuels is at least three times that of producing Hydrogen by the steam methane reforming process mentioned by @LubošMotl.

This is a good example of what is potentially good for the planets costs more at present.

Farcher
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