Hydrogen Power: Separating Gas from Salt Water for Energy

Thread starter WCOLtd
Start date Mar 22, 2009
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Hydrogen Power

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The discussion focuses on the amount of hydrogen gas that can be extracted from salt water per kilowatt-hour of energy. It is noted that the bond energy of water is 918 kJ/mol, translating to approximately 51 kJ/g. Given that electrolysis operates at about 75% efficiency, the energy required for hydrogen production is around 68 kJ/g. Consequently, for a kilowatt-hour, which equals 3.6 MJ, the extraction rate is estimated to be 529 grams of hydrogen per hour. The conversation also touches on methods for collecting the hydrogen produced through this process.

Mar 22, 2009

WCOLtd

How much hydrogen gas can be separated from salt water for every kilowatt/hr of energy? Rough approximations are fine.

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Mar 22, 2009

anarchospider

And how to collect the hydrogen?

Mar 22, 2009

russ_watters

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Well, the bond energy of water is 918 kJ/mol or 51 kJ/g. If electrolysis is typically 75% efficient, you'd need 68 kJ/g. A kWh is 3.6MJ, so that's 529 g/hr.

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