Waste-to-Energy Technologies: Renewable Energy Utilization for Resource Recovery

Dear Colleagues,

The shift toward a circular economy has become a central objective for governments, industries, and communities striving to meet ambitious Net Zero and sustainability targets. Within this transition, the "Waste-to-Energy" (WtE) concept remains essential, encompassing the processes that convert waste streams into useful energy as heat, electricity, or fuels. However, the scope of resource recovery now reaches well beyond energy generation. The integration of renewable energy sources into recovery systems, together with careful attention to their economic viability and policy context, is opening new pathways to recover energy, materials, and nutrients while minimizing environmental impact across the entire value chain.

This Special Issue addresses to/focuses on integrated waste-to-resource systems through the combined lens of renewable energy utilization and resource recovery, with particular emphasis on the environmental, economic, and policy dimensions that determine whether these systems can be deployed at scale. It welcomes contributions on waste-to-energy and -resource recovery technologies, such as anaerobic digestion and , thermochemical conversion routes (gasification, pyrolysis) of agri-food wastes for a circular bioeconomy, nutrient recovery and (hydro)thermal treatments. Alongside technological advances, the issue seeks work on the techno-economic assessments, policy and regulatory frameworks that shape the adoption of these solutions, reflecting the interdisciplinary scope of the Environmental Economics, Energy Systems and Policymaking section.

This Special Issue aims to present and disseminate the most recent advances in waste-to-resources technologies, from process-level innovation to the systemic, economic, and governance factors that enable their implementation.

Topics of interest include (but are not limited to) the following:

• Renewable energy integration in waste-to-energy and resource recovery systems.
• Advances in resource recovery from waste technologies.
• Advances in fermentation technologies (bio-hydrogen, bio-methane, etc.).
• Process design, modelling and optimization of waste-to-resources systems.
• Renewable gases production and optimization.
• Techno-economic and Life cycle assessment of novel waste recovery systems.
• Environmental and energy policy, regulation, and societal impact of waste-to-resources systems.
• Novel systems for waste heat recovery.
• Bio-resource recovery (i.e., methanol, methane, VFAs, flue gases, etc.).
• Nutrient recovery technologies.
• Resource recovery and energy management.

Dr. Christian Aragón-Briceño
Dr. Panagiotis Boutikos
Dr. Musa Manga
Guest Editors

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• resource recovery
• bioresource recovery
• recycling
• thermochemical technologies
• biomass
• bio-hydrogen
• biogas
• nutrients
• waste heat
• life cycle assessment
• energy management
• biochar/hydrochar
• soils
• process modelling
• CO₂