Resumen
In recent years, the Municipality of Piraeus has focused efforts on the improvement of efficiencies in the management of waste collection, which constitutes a major activity and involves complex processes such as vehicle routing and scheduling. The overall goal is to establish improved routes for the garbage collection service in an effort to gain significant savings in terms of total travelled time and energy consumption. The proposed solution approach consists of two main phases, namely a construction and an improvement phase. An initial feasible solution is generated within the construction phase utilizing the sequential insertion ? based construction algorithm of Solomon. Geographical criteria are considered and the distance among bins constitutes the selection factor. One route is constructed at a time and the best un-routed bin is inserted to the best position at each iteration of the construction process. On return, the improvement method employs a metaheuristic Tabu search algorithm equipped with an ?exchange? and a ?relocate? edge-exchange neighborhood structures to drive the search process to improved solutions. In the case of Piraeus city, the design process was particularly complex since there are multiple restrictions and limitations for consideration as well as issues to be resolved. Nevertheless, computational experiments demonstrated the competitiveness of the proposed solution approach. The re-designed routes in the pilot application gain reduced total distance travelled and improved energy efficiency. Future actions are planned, for a large scale implementation and the development of a unified efficient waste collection system.