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Battery electric vehicles (BEVs) are considered one of the most promising solution to improve the sustainability of the transportation sector aiming at a progressive reduction of the dependence on fossil fuels and the associated local pollutants and CO2 emissions. Presently, the major technological obstacle to a large scale diffusion of BEVs, is the fairly low range, typically less than 300 km, as compared to classical gasoline and diesel engines. This limit becomes even more critical if the electric vehicle is operated in severe weather conditions, due to the additional energy consumption required by the cabin heating, ventilating, and air-conditioning (HVAC). The adoption of vapor-compression cycle, either in heat pump or refrigerator configuration, represents the state-of-the-art technology for HVAC systems in vehicles. Such devices typically employ an expansion valve to abruptly reduce the pressure causing the flash evaporation of the working fluid.

The port-logistic industry has a significant impact on the urban environment nearby ports and on the surrounding coastal areas. This is due to the use of large auxiliary power systems on ships operating during port stays, as well as to the employment of a number of fossil fuel powered road vehicles required for port operations. The environmental impact related to the use of these vehicles is twofold: on one hand, they contribute directly to port emissions by fuel consumption; on the other hand, they require some of the ship auxiliary systems to operate intensively, such as the ventilation system, which must operate to remove the pollutants produced by the vehicle engines inside the ship. The pathway to achieve decarbonization and mitigation of energy use in ports involves therefore the adoption of alternative and cleaner technology solutions for the propulsion systems of such port vehicles.

The port-logistic sector has a crucial role in goods transport, as the 85-90% of international trade is achieved by means of maritime routes. The latest reports from the International Maritime Organization show that the port-logistic related activities are an important source of air pollution, both for the use of large auxiliary power systems on ships, which operate during port stays, as well as for the employment of fossil fueled road vehicles for on-site operations. As a matter of fact, the most important maritime facilities are located nearby urban areas and therefore reduction of the environmental impact in ports becomes of primary importance. Thus, in the pursuit of a greener in-port mobility, a progressive replacement of fossil fuels with cleaner alternatives must be promoted. This paper presents the analysis of the performance of a hydrogenfueled plug-in fuel cell/battery hybrid vehicle for cargo-handling in roll-on and roll-off port operations.

Nowadays, fuel economy and pollutant emissions are keenly felt topics and hybrid electric vehicles (HEVs) represent the best opportunity to respond to this problem in the short term. Hybrid electric vehicles meet the high-efficiency of electric motors, with the high reliability of the internal combustion engines, granting optimal results both in terms of emissions and fuel economy. The vehicle and path features highly affect the architecture choice. A parallel architecture, having a more flexible layout and providing a higher drive power, is more suitable for long paths and higher speeds, while the series one better adapts to urban cycles, as can be switched to a pure electric mode. At the same time, a parallel-series architecture is in general a good choice.

This paper describes and compares different powertrain configurations for the retrofit of a heavy-duty Class 8 truck, powered by a 12.6 liters diesel engine. The engine is firstly equipped with an electrification-oriented organic Rankine cycle (ORC) system and then coupled to a traction electric machine into a hybrid powertrain. An electrification-oriented ORC system can produce enough energy to cover the ancillary loads, which in long-haul applications for freight transportation are quite demanding. Nevertheless, only powertrain hybridization can achieve significant improvements in the overall system efficiency. Both systems may thus be implemented in the same vehicle, but an efficiency improvement is guaranteed only if the system is carefully managed so as to reach a trade-off between the requirements and potential benefits of the ORC system and those of the hybrid powertrain.