It is imperative to mitigate climate change and transition towards sustainable energy solutions that drive the exploration of efficient long-term energy storage technologies. Renewable energy sources can play a crucial role in reducing greenhouse gases linked to climate change but face challenges due to their intermittent nature. This thesis investigates thermochemical energy storage systems based on Limestone, with a focus on enhancing performance through nanomaterials and specifically in the form of ternary metal oxide additives. The introduction contextualizes the research within the context of rising greenhouse gas emissions and the EU's goal of achieving carbon neutrality by 2050. It underscores the importance of renewable energy and the need for reliable storage solutions to balance supply and demand effectively. Limestone-based thermochemical energy storage emerges as a promising avenue due to its abundance and capacity for significant energy storage. The literature review highlights the role of additives in improving the performance of thermochemical energy storage systems. It identifies gaps in current research and suggests avenues for further exploration, emphasizing the need for systematic evaluation of additives' effects. The methodology section outlines the approach taken in this study, including additive synthesis, materials characterization, and experimental procedures for evaluating energy storage performance. It provides a framework for conducting controlled experiments and analysing results. Experimental findings demonstrate the effectiveness of ternary metal oxide additives in enhancing Limestone-based thermochemical energy storage systems. CaZrO3, Ca2Fe2O5, and Ca12Al14O33 (Mayenite) additives show promise in improving cycling stability and energy storage capacity. The detailed characterization studies in this thesis reveal insights into additive properties and their interactions with Limestone. The conclusion summarizes key findings and discusses their implications for advancing long-term energy storage technologies. Ternary metal oxide additives offer a pathway towards more efficient, reliable, and scalable energy storage solutions, aligning with global efforts to combat climate change. Overall, this thesis contributes to the ongoing discourse on energy storage by addressing critical challenges and exploring innovative solutions. By optimizing Limestone-based thermochemical energy storage systems, it advances the transition towards a low-carbon energy future, supporting the integration of renewable energy sources and promoting sustainability.

2025-12-02 JG: Author's signature removed from PDF