Is hydrogen the solution?
when making blue hydrogen, but Human Rights NGO Global Witness calculated that blue hydrogen facilities in Canada managed by Shell are only capturing up to 48% of emissions it produces. 4 This could be due to gas leaks along pipes, which is releasing methane into the atmosphere and having a worse effect on the planet compared to CO 2 emissions. Robert Howarth, Cornell University, a critic of blue hydrogen. states:
The greenhouse gas footprint of the blue hydrogen is worse than if you simply burnt the natural gas directly for a fuel . . . it’s a direct strategy of the oil and gas industry . . . pure marketing . . . the goal is to keep selling fossil fuels to the world while pretending it’s going to get better. 5
Only a fraction of hydrogen made is green hydrogen due to its high cost and not being viably commercial, but that is set to change in the near future. This is because electrolysers are becoming cheaper to upscale manufacture large quantities of hydrogen and, with the emergence of more renewable energy sources, prices have fallen gradually and will continue to do so. BloombergNEF predicts that green hydrogen prices will drop to the point where green hydrogen will be cheaper than blue hydrogen by 2030 and grey hydrogen by 2050. 6 Most hydrogen produced is blue hydrogen, which typically arises from steam-methane reforming, which is an endothermic process. With the use of high-temperature steam (700 ° C-1000 ° C), 7 methane reacts with steam within the presence of a catalyst, typically nickel, to produce hydrogen, carbon monoxide and small amounts of carbon dioxide. With the created carbon monoxide, this undergoes a water-gas shift reaction, where it reacts with steam and a catalyst (iron oxide) to produce carbon dioxide and more hydrogen. To successfully isolate pure hydrogen, a process called pressure-swing adsorption is used to remove carbon dioxide and other impurities.
Steam-methane Reforming Reaction: CH 4 + H 2 O → CO + 3H 2 Water-gas Shift Reaction: CO + H 2 O → CO 2 + H 2
Another similar method to steam-methane reforming is partial oxidation, where methane and hydrocarbons react with limited oxygen, so that hydrocarbons are not fully oxidized to carbon dioxide and water. With the oxygen limitation, the main products formed will be carbon monoxide, hydrogen and very small amounts of carbon dioxide in comparison to steam-methane reforming. As a result of the increase in carbon monoxide, the water-gas shift reaction is better used to create more hydrogen and carbon dioxide. Due to partial oxidation being an exothermic process, this process has a faster rate of reaction than steam-methane reforming and requires a smaller reactor vessel for the reaction to occur. However, as shown below by the chemical reactions of partial oxidation, there is less production of hydrogen per unit of input of fuel, than that obtained by the steam-methane reforming process with the same fuel. 4 The truth about hydrogen: https://www.youtube.com/watch?v=AGTjKJHu99c. 5 Ibid. 6 Ibid. 7 https://www.energy.gov/eere/fuelcells/hydrogen-production-natural-gas- reforming#:~:text=In%20steam%2Dmethane%20reforming%2C%20methane,for%20the%20reaction%20to% 20proceed.
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