Sustainability Assessment of Energy System Transition Scenarios in Gotland: Integrating Techno-Economic Modeling with Environmental and Social Perspectives

Gotland has been designated by the Swedish government as a pilot region for the transition to a sustainable, fossil-free energy system by 2030. This transformation emphasizes local renewable energy production and system independence. Within this context, this study investigates the role of industrial waste heat as a resource to improve energy efficiency and support sector integration between electricity, heating, and industry. A mixed-methods approach was used, combining techno-economic energy system modeling, life cycle assessment, spatial GIS data, and stakeholder input. The study develops and analyzes future carbon-neutral energy scenarios for Gotland’s energy system. Industrial waste heat can significantly reduce primary energy demand, particularly in scenarios with expanded industry, carbon capture, and increased sector integration—such as through district heating. In such cases, up to 3000–4000 GWh/year of low-temperature industrial residual heat becomes available, offering substantial potential to improve overall energy efficiency. The scenarios highlight synergies and trade-offs across environmental, economic, and social dimensions, emphasizing the importance of coordinated planning. Scenarios with offshore wind enable energy exports and industrial growth but raise challenges related to emissions and public acceptance, while scenarios without cement production reduce environmental impact but weaken local economic resilience. Limitations of the study include the exclusion of global supply chain impacts and assumptions about future technological costs. The study underscores the need for integrated planning, regulatory innovation, and stakeholder collaboration to ensure a just and resilient transition for Gotland.