Optimizing crop residues collection patterns in rural areas to reduce transportation costs and carbon emissions

Cost optimization of biomass collection is indispensable for its increased utilization, especially in rural areas where crop residues (CRs)-based biomass is in abundance and energy is usually in short supply. However, due to the discrete distribution of rural settlements, the increasing economic and environmental costs associated with CRs collection have become key factors limiting its application. Therefore, this study proposes a method for optimizing the spatial pattern of CRs collection in rural areas while also considering transportation costs and carbon emissions reduction. Based on a multi-scenario location-allocation model, a CRs collection pattern was constructed for biomass resource points and energy facilities. An empirical study in Fujin County found that as CRs collection distance threshold (CDT) increased, transportation costs and carbon emissions reduction potential tended to increase and gradually converge. When the CDT was taken for 15 km, the spatial pattern of CRs collection maximized the overall benefits of transportation costs and carbon emissions reduction, with a transportation cost of 898,104 yuan and a carbon emissions reduction potential of 501,627.5 t. The optimal spatial pattern for collection achieved the collection-utilization spatial matching of 647 biomass feedstock resource points and 196 villages in the study area, resulting in the exploitation of 84% of CRs in total. 25% of villages in the study area can independently meet their heating needs through CRs, and 75% need to consider mixed energy sources for heating. This method can support planning and decisionmaking for the distributed development and sustainable utilization of biomass resources in rural areas.