Environmentally significant non-agricultural biomass for sustainable bioenergy: Sources, conversion, and environmental benefits

The escalating challenges of non-agricultural accumulation and global energy demands underscore the need for innovative waste-to-energy solutions that mitigate environmental impacts and address food-fuel conflicts. This review advances the field by exploring non-agricultural biomass- municipal solid waste, forestry residues, industrial organic waste, algal biomass, textile waste, and invasive plant species as sustainable feedstocks for bioenergy production, supporting waste management, energy security, and circular bioeconomies. Their physicochemical properties, conversion technologies (pyrolysis, gasification, anaerobic digestion, and hydrothermal liquefaction), and challenges, like feedstock heterogeneity and high moisture content, are evaluated. Advanced pretreatments enhance conversion efficiencies, while technologies yield significant environmental benefits, including methane emission reductions and carbon sequestration. Socio-economic advantages include job creation, reduced fossil fuel dependency, and alignment with sustainable development goals for clean energy and sustainable cities. To address scalability gaps, this review introduces three novel contributions: (1) an AI-integrated urban biorefinery framework leveraging plasma gasification and AI-driven sorting to optimize heterogeneous feedstocks; (2) valorization strategies for understudied feedstocks like invasive species, enhancing bioenergy outputs through hybrid systems; and (3) scalable pathways tailored to urban and rural waste systems. Policy incentives, such as carbon taxes, are critical for economic viability, enabling these strategies to support global net-zero emissions goals by 2050 through sustainable waste-to-energy systems.