Objective: decongest traffic and improve last mile delivery

Estimates suggest that four million parcels are delivered every day in Spain, most of which are destined for the metropolitan areas of large cities, which is where 55% of the country's population lives. Parcel delivery rates skyrocketed during the Covid-19 pandemic in particular, as a result of the increase in online shopping, which has continued to grow by double-digit rates even since the end of the pandemic. This new mobility has aggravated the problems of traffic congestion, lack of parking and poor air quality that have been issues in urban areas for years.

As part of the EU's commitment to finding innovative solutions to reduce the negative impacts of urban freight transport, promoting intermodal transport, reducing traffic and optimizing deliveries, a group of researchers from the Universitat Politècnica de València, the Universitat Obera de Catalunya and the Universitat Autònoma de Barcelona have devised a proposal for an urban goods distribution network. "We have been studying possible solutions for years, and in addition to determining that there is no single option, we have found that much closer collaboration between the public sector and the private world is necessary," explained Cristian Castillo Gutiérrez, a member of the Faculty of Economics and Business at the Universitat Oberta de Catalunya (UOC) and a researcher in the Sustainability, Management and Transport (SUMAT) research group.

The proposed design of the network, which has been published in open access in the European Transport Research Review, focuses on the city of Barcelona, where the researchers identified 1,057 locations for parcel delivery points. The proposal is for micro-hubs located in existing public transport stations, markets, shopping centres, post offices, car parks, buildings and collection points. "Some public car parks have already given over spaces to private parcel companies, and we would need to see what investment the other points proposed require so that they can be created," said Castillo.

The other participants in the study were Eduard Josep Álvarez Palau, who is also a professor in the Faculty of Economics and Business and a SUMAT researcher; Javier Panadero Martínez, a professor in the Department of Computer Architecture and Operating Systems at the Universitat Autònoma de Barcelona; and Ángel A. Juan, a professor of Data Analytics and Operations Research at the Universitat Politècnica de València.

A routing algorithm

The authors not only identified these thousand potential intermodal micro-hubs for more efficient delivery of parcels in Barcelona, but they also developed an agile routing algorithm to optimize the work of delivery drivers. Equally importantly, they also advocated deliveries with cargo bikes and electric vans in order to contribute to improving the city's air quality and reducing greenhouse gas emissions.

The algorithm they developed generates adaptive distribution plans which take into account micro-hub operating costs and vehicle routing costs, and uses heuristic and machine learning methods enhanced by parallelization techniques. It uses artificial intelligence to quickly produce high-quality routing plans based on transport infrastructure and modes of transport and delivery points. The algorithm adapts dynamically, and uses multi-objective techniques so that each routing plan attains what is known as Pareto efficiency, which means that it produces plans in which it is impossible for any gain to be made in a variable without a loss elsewhere.

According to Cristian Castillo, the real-world testing carried out in Barcelona has shown "promising results", as it provided potential scenarios for reducing greenhouse gas emissions and improving delivery times, and satisfying parcel companies, workers in the sector and the final recipients of the parcels.

Smart routes for rural areas

In a previous study, Professors Castillo and Álvarez used routing algorithms to increase the efficiency of healthcare professionals' journeys in areas located more than 45 minutes from a primary medical care centre on foot or by bicycle. The algorithms created, which are scalable and customizable, design the most efficient routes according to parameters including priorities, visit times and distance of travel. The authors carried out a simulation in Segovia, a province where 11.8% of municipalities are located more than a 45-minute walk from a primary care centre, in order to put them to the test.

The ultimate objective of this study, which has been published in open access in the Socio-Economic Planning Sciences journal and is available to the public so that it can be implemented in any region that is interested in doing so, is for all rural areas to have access to healthcare.

Sustainable cities and communities

The proposal for a network for the urban distribution of goods is aligned with number 11 of the United Nations' Sustainable Development Goals (SDGs): Sustainable Cities and Communities. This goal aims to make "cities and human settlements inclusive, safe, resilient and sustainable". Cities represent the future of the global way of life. The world's population reached 8 billion people in 2022, with more than half living in urban areas. This figure is expected to increase and 70% of the population will live in cities by 2050.

Reference

Castillo, C., Panadero, J., Alvarez-Palau, E. J. & Juan, A. A. "Towards greener city logistics: an application of agile routing algorithms to optimize the distribution of micro-hubs in Barcelona." European Transport Research Review. 16, 44 (2024). https://doi.org/10.1186/s12544-024-00669-7