A green multi-objective open vehicle routing problem for reverse logistics with consolidation points and dual time windows

Purpose This paper aims to address a green, multi-objective open vehicle routing problem for reverse logistics, targeting the joint optimization of total cost, CO2 emissions and customer satisfaction. The corresponding model integrates customer-based consolidation points and dual time windows with flexibility in scenarios where returns are operated by third-party logistics (3PL) providers. Design/methodology/approach A mixed-integer linear program is formulated to capture multiple constraints, including vehicle heterogeneity, route duration limits and flexible scheduling needs. Two novel features are introduced: (1) local consolidation points, where selected customers temporarily collect returns from nearby locations, and (2) dual time windows that distinguish between acceptable and preferred service intervals. Findings Results demonstrate the model's ability to explore diverse trade-offs among environmental, economic and service-related objectives. The use of consolidation points and flexible time windows enhances route efficiency while improving customer alignment. The multi-objective solution techniques provide decision-makers with a structured method to evaluate competing goals. Practical implications The proposed model is well aligned with logistics strategies used in sectors such as e-commerce, retail and consumer goods, where returns are handled through 3PL providers and vehicle return trips are often unnecessary. Its integration of consolidation mechanisms and preference-sensitive scheduling has the potential to improve routing efficiency, reduce emissions and enhance customer satisfaction in dense urban environments. Originality/value This study is the first to jointly address cost, emissions and customer satisfaction within an open vehicle routing context while also integrating customer-based consolidation and dual time windows to enhance flexibility and realism in reverse logistics routing.