<![CDATA[Urban last-mile delivery is increasingly shaped by e-commerce growth, rapid-delivery expectations, and motorcycle-based courier operations. Jakarta is a relevant setting because motorcycles dominate road traffic and two-wheelers are widely used for last-mile delivery. This study develops a Jakarta-calibrated scenario simulation to estimate operational carbon dioxide (CO2) emissions under alternative combinations of route optimization, micro-hub consolidation, pickup-point delivery, and electric-motorcycle adoption. The model represents an illustrative 500-courier fleet only as a scaling device; daily courier distance is calibrated at 70 km/day, the midpoint of the 60-80 km/day range reported for Indonesian two-wheeler last-mile couriers, and 300 operating days/year is treated as an analytical normalization rather than an observed company schedule. Baseline emissions are therefore also reported per courier-year. Scenario VKT reductions are literature-informed inputs rather than outputs of an independently solved Vehicle Routing Problem or GIS model. To avoid double counting in the integrated scenario, individual distance-reduction effects are compounded and constrained by an explicit 40% VKT-reduction cap. Electric-motorcycle electricity use is set at 0.025 kWh/km, with a 10% charging-loss allowance, and electricity emissions are calculated using a Jakarta-relevant Java-Madura-Bali (JAMALI) grid factor of 0.87 kg CO2/kWh. Under the calibrated baseline, the illustrative fleet travels 10.50 million km/year, consumes 300,000 L of gasoline, and emits 693.0 tCO2/year (1.386 tCO2 per courier-year). Conditional on the scenario inputs, route optimization, micro-hub batching, and pickup-point consolidation correspond to 12.0%, 18.0%, and 25.0% lower emissions, respectively. A route-optimization plus 40% electric-motorcycle scenario produces an estimated 38.9% reduction, while the integrated scenario produces an estimated 62.9% reduction and 70.8% lower energy expenditure. These values should be interpreted as scenario-contingent estimates, not observed treatment effects. The analysis indicates that reducing avoidable vehicle-kilometers before electrifying the remaining travel is a promising decarbonization sequence for motorcycle-dominant urban delivery systems.]]>
