Towards the decarbonization of maritime public transport in Venice: an LCA based environmental impact assessment

This thesis aims to analyse the environmental impacts arising from the decarbonization of the fleet of AVM S.p.A. - ACTV, the public transport operator in the historic centre of Venice. The current fleet, comprising around 150 vessels, is largely equipped with internal combustion (diesel) engines. This configuration contributes significantly to the city’s air pollution, problems exacerbated by the so-called ‘canyon effect’ of Venice’s canals, which hinders the dispersion of local pollutants. The main objective is to compare the current environmental impacts of the baseline scenario with those of a hybrid (diesel-electric) propulsion model using a Life Cycle Assessment (LCA), focusing the analysis specifically on the propulsion system. To do this, the study will address the retrofit strategy, namely the replacement of the propulsion system in vessels already in use. According to this approach, the processes related to the hull’s life cycle are not taken into account in the LCA model, thereby enabling a comparative analysis of the propulsion systems. Furthermore, retrofitting represents an optimal strategy for mitigating emissions, as it ensures the reuse and extension of the life cycle of hulls that are still operational, thereby avoiding the emissions associated with building entirely new fleets.