Muhaimin Iqbal
Author

Green Hydrogen Cost Driver

Advanced Renewable

Tue , 14 May 2024 12:47 WIB

A common source of clean energy, available everywhere humans live, is water. In very large quantities it is in the sea for wave and tidal energy, in large quantities it is in rivers for hydropower, in moderate amounts it is used for steam power, and in relatively small but very powerful quantities it is water from which hydrogen is splitted.

The last one, hydrogen (H2) which is separated from water (H2O) is idolated by the world to be the next clean energy solution as a replacement for fossil energy whose use must be controlled. Dozens of world giant companies even guarantee their support for green hydrogen produced from this water with so-called green hydrogen pledges.

So what's the problem with this hydrogen? isn't it easy to separate H2 from H2O? It's easy, with an electric current, two water molecules (2H2O) will be electrolyzed to become 2H2 and O2. But this requires a very large amount of energy, which is shown by the delta enthalpy of this reaction, +572 MJ/kmol or about 39.75 kWh per kg H2.

Due to the high energy requirement, feasible production of green hydrogen from water electrolysis can only be feasible if two conditions are met, namely a very cheap electricity source, and the electricity source must be clean and from renewable energy.

Another way to separate H2 from H2O is not through water electrolysis but using the Water Gas and Water Gas Shift reactions. In this way, 1 carbon atom reacted with 2H2O will produce 2H2 and 1CO2, the delta enthalpy for this is only 90 MJ/kmol or around 6.25 kWh per kg H2.

Because the energy consumptions are very low compared to using electrolysis, plus the cost of carbon or charcoal, this second production technique will still be much cheaper than even the cheapest way of electrolyzing water with electricity.

This is good news for the world's clean energy community, that green hydrogen can now be produced relatively easy and also low cost. All that is needed for this is a reactor that we call XH2M, Extra high Hydrogen and Membrane. This technology will be introduced to the world renewable energy community through the International Conference on Renewable Energy Gas Technology (REGATEC 2024) in Lund, Sweden - this coming week.