Strategies, models, and methods for energy-system expansion planning and industrial energy efficiency

Both the scientific community and political institutions frequently stress the crucial role of renewable energy sources and industrial energy efficiency in mitigating climate change and achieving sustainable development goals. Energy-system expansion planning is a key component of energy and economic development, aiming to determine long-term strategies for expanding generation, storage, transmission, and distribution systems while respecting techno-economic, environmental, and political constraints. Despite the existence of a large stream of research on energy-system expansion planning, there are aspects related to the methodology's applicability and system dimension that need to be improved, mainly concerning the concept of resolution in time, space, techno-economic detail, and sector coupling. At the same time, stricter regulations, intense business competition, and growing public pressure have increasingly driven companies to incorporate environmental concerns into their strategic planning. Therefore, identifying strategies and providing ready-to-use tools to improve energy efficiency has become a significant area of interest for researchers and practitioners. This thesis aims to advance the fields of energy system expansion planning and industrial energy efficiency by exploring the interplay among techno-economic, environmental, and political factors. On the one hand, it proposes models and case studies to support policymakers and practitioners in decarbonizing energy systems, focusing on generation, storage, and dispatching levels. On the other hand, it offers strategies and ready-to-use tools to reduce the carbon footprint of energy-intensive industrial sectors. The research activity follows a logical-conceptual framework that focuses on three main research areas: classifying planning models and tools for energy policy analysis, improving decision-making tools to address the complexities of modern energy systems, and enhancing energy efficiency in high-emission industrial sectors. The findings offer a solid foundation for future research aimed at developing integrated and actionable solutions to accelerate the sustainable energy transition.