Where should Hydrogen be used first?

In the final part of Jee’s spotlight on Hydrogen, Hasib Rahmani looks at one of the most pressing questions in the current climate: where should our supplies of the renewable energy be directed first?

To understand where Hydrogen power should be diverted, we first need to understand which greenhouse gases pose the greatest threat.

Under the Kyoto protocol there are seven direct greenhouse gases (GHGs): 

• Carbon Dioxide (CO₂) 

• Methane (CH₄) 

• Nitrous Oxide (N₂O) 

• Hydrofluorocarbons (HCFs) 

• Perfluorocarbons (PFCs) 

• Sulphur Hexafluoride (SF₆) 

• Nitrogen trifluoride (NF₃) 

Of these, Carbon dioxide is by far the biggest contributor to climate change making up ~75%, followed by methane and nitrous oxide which make up about 20% and the remaining gases constitute the remaining 5%. 

To reduce these emissions there needs to be an increase in blue and green hydrogen. Blue hydrogen is created using natural gas as the fuel source for steam methane reformation, with the carbon created from the process recaptured and stored or utlilised. Green is created using renewable energy to power electrolysis. Currently, the predominant form of hydrogen creation is grey, which uses the same creation process as blue hydrogen but without capturing the carbon produced.

Once this move towards blue and green hydrogen is achieved there needs to be a decision on what is the most cost-effective use of hydrogen for GHG emissions.

This graph shows the mass of CO₂ saved for every 1MWh of electricity used from renewable (net-zero) sources instead of fossil fuels ​(Carbon Commentary, 2021)​. The greatest savings in GHG’s will be reducing coal use for power generation followed by using electric vehicles. The least efficient being generation of ammonia to replace heavy oil for shipping. 

This shows that the most beneficial use of hydrogen will be to replace coal/gas as a heating source for power generation or heat generation. Therefore, sectors such as commercial and urban power generation, steel production and other metal production should be the first to be pushed in adopting hydrogen. 

To read more on Hydrogen click here to download Jee’s Hydrogen capability statement.