Chapter 8 - Sustainable Logistics with Cargo Bikes - Methods and Applications

Growing urbanization, climate change and the increasing use of home delivery require new ideas of how to solve transportation-related problems in urban areas. The cargo bike, once a common mode of transport, played a minor role in the last decades of motorization. Yet, the cargo bike is perfectly suited for inner-city transportation. It is quiet, emission-free and less disturbing for the citizens. However, it is necessary to take the differences to conventional trucks or vans into account. In this paper we will show different ways of using cargo bikes for freight transportation in inner-city areas and present different scenarios for the efficient use of cargo bikes. In the simplest case the optimization problem corresponds to a shortest path problem. Otherwise, the optimization problems can be either one-echelon or two-echelon. The first type corresponds to a vehicle routing problem (VRP), while the latter one results in a two-echelon VRP (2E-VRP). These are the most common types, but also systems with more than two echelons can be observed. In the 2E-VRP, freight is transported from the depot(s) to rendezvous points, so-called satellite facilities, from which it is transported in the second echelon to the final customers. The 2E-VRP can either incorporate synchronization constraints between the first and second echelon depending on whether the possibility of intermediate storage at the satellites is given or not. Other distinguishing factors are the number of depots, heterogeneous or homogenous fleets, time window constraints etc. The problems can be either deterministic or stochastic in nature and might refer to a static or dynamic environment. We will describe the resulting optimization problems in detail and present the relevant literature and state of the art solution methods. Finally, we will describe some applications of the successful use of cargo bikes in European cities.