Comparative life cycle assessment of hydrogen production in Iceland and the EU-27

As the world looks to limit the use of fossil fuels as the impacts of climate change continue to be realized, hydrogen is set to be a major contributor to decarbonize the global economy. Renewable energy in Iceland, consisting of geothermal and hydropower, can be a part of Europe’s decarbonization strategy. Renewable electricity can split water into its molecular components of hydrogen and oxygen. The green hydrogen created by this electrolysis can be used as a sustainable energy carrier. In this thesis, a comparative life cycle assessment (LCA) of water electrolysis in Iceland and the European Union is presented. The main impact assessment category used to compare the different scenarios was the global warming potential measured in carbon dioxide equivalence. Results for other impact categories were also calculated and can be found in Appendix B, but are not discussed thoroughly in this paper. The research question this thesis sought to answer was: Is the production of hydrogen in Iceland for use in mainland Europe more environmentally beneficial than producing hydrogen in Europe? The functional unit of 1 kg of Hydrogen molecules was utilized to allow for comparison between the scenarios explored in this research, as well as other works on the subject. The LCA in this paper was conducted using the GaBi software and ecoinvent database. Three electrolyser technologies were considered: alkaline electrolysers, proton exchange membrane electrolysers, and solid oxide electrolysers. The three different types of electrolysers were analyzed in both Iceland and the EU. Three methods of storage for the produced hydrogen were considered: liquid hydrogen, ammonia, and methanol. The life cycle inventory for the electrolysers, their operation, and the storage of the hydrogen were built using data synthesized from sources during literature review. The final scenarios considered in this thesis were of hydrogen production by electrolysis of the three electrolysers using theoretical electricity grids in the European Union in 2030 and 2050 based on their climate policy goals for those years. This comparison serves to help answer the question of whether IV producing hydrogen in Iceland for use in mainland Europe would continue to be beneficial in the future from an emissions standpoint. Based on the results of the GaBi modelling, the lowest environmental impact measured by carbon emissions, comes from producing hydrogen with a solid oxide electrolyser in Iceland then storing and transporting it as liquid hydrogen. This results in carbon dioxide equivalent emissions of 0.946 kg per 1 kg of H2. The lowest impact in terms of emissions for the European scenarios is electrolysis by a solid oxide electrolyser stored as ammonia at a value of 17.113 kg CO2 equivalence. This value is greater than all the values for hydrogen production in Iceland even with transport included suggesting that producing green hydrogen for use in mainland Europe is less environmentally impactful. The best result for the production of 1 kg of hydrogen by electrolysis in the 2030 and 2050 European Union cases were for electrolysis with a solid oxide electrolyser having values 8.91 and 1.56 kg of CO2 equivalence respectively. Both these values are greater than all the results for electrolysis in Iceland by all three electrolyser types. This suggests that in the future even if/when the European Union is able to reach its climate policy goals for their electricity mix, it will still be less environmentally impactful in terms of global warming potential to produce green hydrogen in Iceland