Hydrogen is a near zero-carbon energy carrier. In decarbonising our planet, high temperature industrial processes and heavy freight have not identified convincing pathways to decarbonisation. Given its energy density coupled with safety challenges, can heavy freight and high temperature industrial processes facilitate the safe and initially near zero carbon application of hydrogen as it transforms to a zero-carbon option?
A recent report from Arup (A Future Hydrogen Economy, 2019) stared that hydrogen could play a role in decarbonising UK energy, but states that hydrogen use will need policy changes and commitments, provided there are enough demonstrators to validate the correct scenarios for its use. Consumer engagement will be an important element of this work as hydrogen has significant consumer perception issues to overcome. Network capacity will be an important aspect for distributing hydrogen, especially from updated gas distribution networks. However, there is a query over use of the gas transmission network for hydrogen.
Current research will also need to focus on electrolyser efficiency. Improvements in efficiency will facilitate both current projects that consider use of natural gas as a hydrogen source when combined with adjacent Carbon Capture and Storage (CCS). CCS has only 2 large scale operating projects in Norway based on redundant North Sea oil production facilities. The UK is proposing 5 CCS plants and Ireland is proposing 1 plant – all from the mid 2020’s onwards.
Therefore, this leaves renewable energy as the provider of excess electricity. Wind power in the UK has 30% availability and current electrolyser technology is of the order of 60% efficiency. The need for more advanced electrolysers is therefore paramount. But the final challenge is electrolyser location. If the gas distribution network is suitable, this would require local distributed plants placed adjacent to the gas network. We are once again faced with moving large amounts of renewable electricity to points on the network where a demand will occur. The question has to be economic in bringing together a decarbonisation strategy that works for all.
Professor Neil J Hewitt