Economics of Hydrogen Production

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Hydrogen has been proposed as carbon-free alternative fuel to hydrocarbons provided the hydrogen is produced from a carbon-free source e.g. renewable or nuclear electricity

The electrochemistry of producing hydrogen (and oxygen) from water using is well understood. One FARADAY (96,485 COULOMBS) is required to produce one mole of hydrogen atoms - or half a mole of hydrogen molecules (H2). Therefore an electric current of 1 AMP will in 1 SECOND produce 0.5/96485 = 5.18E-06 moles H2. Assuming a cell VOLTAGE of 1.481V that equates to 3.5E-06 moles H2 per W-s; 0.0126 moles H2 per W-h; 12.6 moles H2 per kW-h; 25.2 GRAMS H2 per kW-h. As hydrogen has a higher calorific value than natural gas (112 MJ/kg versus 50 MJ/kg) multiply by this ratio (112/50) to get 56.4g natural-gas-equivalent per kilowatt-hour electricity

How does the price of hydrogen produced from by electrolysis compare to the cost of natural gas? For electricity @ 8.8p per kW-h and natural gas @ 4.3p per kW-h, the 25.2 g H2 (= 56.4g natural-gas-equivalent) costs 8.8p and the actual cost of 56.4g natural gas (2.82 MJ; 2820 kJ; 0.784 kW-h) is 3.4p

In other words hydrogen from electricity costs about 2.6x the equivalent amount of natural gas