Circular biorefineries for rural India: turning rice straw and bagasse into biofuels

India’s abundant rice straw and sugarcane bagasse remain underused and are often burned, worsening air pollution. This review examines how circular biorefineries can convert these lignocellulosic residues into biofuels, advancing energy security, rural incomes, and environmental goals. We interrogate the value chain, from feedstock aggregation and densification to conversion and deployment, comparing physico-chemical pretreatments (e.g., steam explosion and alkaline) with emerging green options and clarifying trade-offs among delignification, fermentable-sugar yield, and inhibitor formation. We evaluate biochemical (enzymatic hydrolysis, and fermentation) and thermochemical (gasification and pyrolysis) routes to a diversified product slate. Evidence favors decentralized, village-scale mini-biorefineries led by Farmer–Producer Organizations, contingent on affordable enzymes, robust microbial catalysts, supportive policy, innovative finance, and disciplined supply-chain governance, a pragmatic roadmap for India’s circular bioeconomy.