On the role of storage for electricity in the energy transition, with special focus on hydrogen

In Europe, ambitious targets for renewable energy adoption have been set, indicating a significant shift towards wind and solar energy in shaping the European electricity landscape. This transition underscores the increasing importance of integrating storage for electricity, particularly as renewable generation increases and dispatchable thermal generation capacity decreases. The core objective of this dissertation is to conduct an in-depth techno-economic analysis and explore the future economic perspectives of various storage for electricity options. The focus is particularly on the complete decarbonization of the electricity system and the resulting interplay between storage and variable renewable electricity generation, such as wind and photovoltaic sources and the utilization of hydrogen. This dissertation is primarily based on eight scientific publications: four review papers covering storage technologies, technological learning and hydrogen and four papers addressing: i) future scenarios for electricity storage under varying renewable integration, demand patterns and weather conditions; ii) current and future costs of integrated storage technologies in a decarbonized power system; iii) economic and environmental assessments of hydrogen production methods and locations; and iv) the potential use of hydrogen in the transport sector, including wind-powered fuel cell electric buses.The research methodology employs electricity system modeling to assess the impacts of electrification and decarbonization, with a specific focus on storage for electricity. Techno-economic analyses scrutinize the feasibility and economic implications of integrating different storage technologies, alongside hydrogen production, transportation and utilization. Key findings underscore the critical role of weather patterns in influencing renewable electricity generation and the need for solutions to ensure seasonal balancing. Cost assessments from 2023 to 2050 reveal significant declines in lithium-ion battery costs compared to stable costs for pumped storage hydro, underscoring the importance of strategic deployment strategies. Hydrogen emerges as a component for specific use cases in the energy transition, with analyses revealing varying economic and environmental impacts of different production methods. Challenges in the transport sector, such as investment costs and operational efficiency, currently limit the widespread adoption of hydrogen applications. In conclusion, strategic planning and investment in storage technologies and hydrogen infrastructure are crucial to enhancing the reliability, cost-efficiency and sustainability of Europe's future renewable energy landscape.