To reduce fossil fuel dependency in shipping, adopting alternative fuels and innovative propulsion systems is essential. Solid Oxide Fuel Cells (SOFC), powered by hydrogen carriers, represent a promising solution. This study investigates a multi-fuel SOFC system for ocean-going vessels, capable of operating with ammonia, methanol, or hydrogen, thus enhancing bunkering flexibility. A thermodynamic model is developed to simulate the performance of a 3 kW small-scale system, subsequently scaling up to a 10 MW configuration to meet the power demand of a container ship used as the case study. Results show that methanol is the most efficient fueling option, reaching a system efficiency of 58% while ammonia and hydrogen reach slightly lower values of about 55% and 51%, respectively, due to higher auxiliary power consumption. To assess technical feasibility, two installation scenarios are considered for accommodating multiple fuel tanks. The first scenario seeks the optimal fuel share equivalent to the diesel tank’s chemical energy (17.6 GWh), minimizing mass increase. The second scenario optimizes the fuel share within the available tank volume (1646 m³), again, minimizing mass penalties. In both cases, feasibility results have highlighted that changes are needed in terms of cargo reduction, equal to 20.3%, or, alternatively, in terms of lower autonomy with an increase in refueling stops. These issues can be mitigated by the benefits of increased bunkering flexibility.

The decarbonization goal by 2050, as set by Directive 844/2018, is an ambitious objective that requires a big effort. The strategy to act on the building sector includes the construction of new highly efficient buildings and the energy refurbishment of the existing ones. This study focuses on the renovation of social housing buildings, which are a wide component of the existing building stock, and in most cases, present poor energy performances. The investigation focuses on the role that social housing plays in the European building stock, from an energy point of view, and through significant examples, review the strategies adopted to improve their energy performances. A significant case study in Berlin, representative of both German and even European social housing, was investigated by selecting energy efficiency measures to improve its performance. In a final configuration that combines different energy efficiency measures, a heating thermal energy saving of 88% was obtained. The study includes a technical economic analysis of the proposed energy efficiency interventions and shows how some of them are not economically convenient without governmental incentives.

It is widely recognized that hydrogen can play an important role in the decarbonization of sectors where emissions are hard to abate such as the mobility sector. The widespread use of hydrogen-based mobility technologies requires the development of hydrogen distribution infrastructures, the scale-up of which is crucial for planning their distribution across an area. In this context, the goal of this study is to evaluate the current European refueling infrastructure and its ability to meet the increasing hydrogen mobility demand, as well as to provide a preliminary design of small, medium, and large-size hydrogen refueling stations (HRSs) basing on estimates of daily demands of hydrogen passenger cars. Starting from the total number of registered hydrogen passenger cars in Europe in 2022 and taking into account the extension of the European Central Road, the number of HRSs (related to different sizes), needed to refuel the road-going vehicles, is evaluated. For a more comprehensive analysis, results are compared with the current European infrastructure of HRSs. To accomplish this, the HRSs size, for each considered scenario, is designed according to a cascade storage system, considering the refueling of cars with a tank capacity of 5 kgH2 at 700 bar and assuming a working time of 6 h/day per HRS.