Sustainable Resource Management: Modelling Energy Systems, Water Ecosystem Services, and Transition Pathways

This thesis explores sustainability and resource optimization in the context of the water-food-energy nexus and the broader ecological transition. It focuses on interdependencies between economic systems, natural capital, and policy strategies, with particular attention to energy systems and water-related ecosystem services. The first chapter examines the role of natural capital in sustainable development by analysing how water provision services —evaluated through the SEEA-EA framework—affect agricultural productivity and resource sustainability. This work highlights the need to balance water demand with ecosystem service capacity to ensure long-term ecological resilience. The second chapter analyses national energy policy, formulating two optimisation models to evaluate Italy's electricity generation mix by 2030. The models minimise financial and environmental costs under different scenarios, highlighting how the integration of renewable energy and risk management can support national sustainability targets. The third chapter shifts to the enterprise level, analysing how non-core energy firms manage energy production, storage, and trading in alignment with ESG objectives and market conditions. A hybrid forecasting and optimisation framework is applied to evaluate how these firms can reduce costs and enhance efficiency while contributing to ecological goals. Together, the study provides an integrated approach to resource management spanning ecosystem services, national policy, and enterprise scales, supporting the transition towards resilient, efficient, and sustainable systems.