From willingness to wait to sustainable impact: Smoothing e-commerce delivery volume peaks

Willingness to wait is often promoted as a path towards more sustainable e-commerce deliveries, yet its impact depends on how firms use the operational flexibility it creates. We analyze two approaches: concentrating deliveries to minimize route distance versus spreading deliveries to smooth peaks and minimize fleet size. We adopt a strategic modeling approach that captures the flexibility created by customers’ willingness to wait and uses continuous route-length approximations to estimate total route distance and fleet requirements. Using e-commerce delivery data from the Netherlands, we find that concentrating deliveries yields substantial distance savings only at very high willingness-to-wait levels and requires much larger fleets, whereas spreading deliveries can reduce fleet size with only a modest increase in distance. Once life-cycle emissions of the delivery fleet are considered, spreading deliveries can therefore lower CO 2 emissions, whereas concentrating deliveries can increase them.