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I have an odd, and possibly naive, question. Why wouldn't it be easier ( and cheaper ) to produce hydrogen from water rather than natural gas?
by A4ET8a8uTh0 5y ago
I have an odd, and possibly naive, question. Why wouldn't it be easier ( and cheaper ) to produce hydrogen from water rather than natural gas?
- bbojan 5y agoHydrogen is bound in both compounds - you need to expand energy to extract it. As in our oxidizing atmosphere natural gas is a source of (chemical) energy, you can burn it to provide the energy needed to extract the hydrogen. This is the steam reforming reaction. Since water is not a source of energy, you need to add (expensive) electrical energy in order to extract the hydrogen. This is the electrolysis reaction.
- thinkcontext 5y agoIt's significantly more expensive to make it from water than methane.
- jandrewrogers 5y agoThe cost of industrial chemistry is largely the amount of energy required to produce a ton of chemical. There are different ways to make any chemical all of which have different cost structures depending on the application. Making hydrogen from water is extremely electricity intensive, around 50 MWh per ton. Even aluminum production from ore, which is famously electricity intensive, only requires a small fraction of the energy input that hydrogen requires when produced this way. Making hydrogen from methane has a more expensive feedstock (methane versus water) but requires vastly less energy which makes it much cheaper overall. I would guess that methane feedstock also requires a less expensive plant per ton of production capacity, which would also lower costs.