Sustainable Material Handling: A Life Cycle Assessment of Different Material Handling Systems

Material handling systems are integral to industrial operations but pose significant environmental challenges due to high energy consumption, resource use, and emissions. This study conducts a comprehensive life cycle assessment (LCA) to evaluate and compare the environmental performance of four prevalent material handling systems—conveyor belts, diesel forklifts, electric forklifts, and automated guided vehicles (AGVs)—under Nigerian operational conditions. The LCA follows ISO 14040/14044 standards, adopting a cradle-to-grave approach with SimaPro 9.6 software and the ReCiPe 2016 impact assessment method. The functional unit is defined as the handling and internal transportation of one tonne of material over one year in a medium-sized Nigerian warehouse. Results reveal substantial disparities in environmental impacts across systems. Conveyor belts exhibit the lowest environmental burden, with climate change impacts of 110 kg CO₂eq per functional unit, primarily due to lower operational energy and absence of direct fossil fuel combustion. Diesel forklifts perform the worst, with 1,652 kg CO₂eq, driven predominantly by direct combustion of high-sulfur diesel during operation. Electric forklifts and AGVs show intermediate impacts (725 kg CO₂eq and 767 kg CO₂eq, respectively), heavily influenced by battery production and carbon-intensive grid electricity. Contribution analysis identifies operational energy use, lithium-ion battery manufacturing, and steel production as key environmental hotspots, accounting for over 85% of total impacts in electric and automated systems. Sensitivity analyses indicate that improvements in grid decarbonization could significantly alter rankings, with AGVs emerging as the most sustainable option under a cleaner electricity mix (0.35 kg CO₂eq/kWh). Monte Carlo simulations confirm the robustness of the ranking: conveyor belts > AGVs > electric forklifts > diesel forklifts under current Nigerian conditions. The study concludes that, in contexts with high-carbon electricity, fixed systems like conveyors are environmentally preferable, while flexible electrified systems like AGVs offer a viable pathway toward sustainability as energy systems decarbonize. Practical recommendations are provided for policymakers, industry operators, and manufacturers to promote sustainable material handling through technology selection, energy transition, and circular economy practices.