This paper presents a practical and communication-independent energy management system (EMS) for a DC microgrid supply within the firezone of a cruise ship. The proposed approach prioritizes operational reliability and fault tolerance under emergency conditions, where communication availability and control complexity should be minimized. The proposed DC microgrid integrates photovoltaic systems (PVs), fuel cell systems (FCs), and lithium-iron-phosphate (LFP) battery energy storage systems (BESSs), coordinated through a rule-based EMS combined with droop-controlled converters. The electrical topology considered in this study is a collaborative development of the project consortium of the publicly funded project Sustainable DC Systems (SuSy), featuring a novel configuration with two independent horizontal busbars for the Cabin Area Distribution (CAD) and Technical Area Distribution (TAD). The EMS can manage two operational scenarios: (i) regular operation, with two decentralized droop controls where power generation is distributed among all generators based on their respective capacities, and a power curtailment strategy is applied to prevent overcharging of BESSs; and (ii) irregular operation, where a fault on one of the vertical busbars triggers the use of reserved battery storage capacity on both sides of the ship and activates load-shedding to ensure continued operation of critical loads and sustain grid functionality. The effectiveness of the proposed architecture is validated through detailed MATLAB/Simulink simulations. Under regular conditions, the EMS achieves stable voltage regulation, balanced power sharing, and efficient energy curtailment. During fault conditions, the battery storage on both sides successfully supports the critical loads. The fuel cells are operated in power-controlled mode effectively up to their full rated 6$\mathrm{k}$$\mathrm{W}$ capacity while the DC bus voltage stabilization is ensured by the battery energy storage systems. These results validate the proposed EMS as a robust and low-complexity solution for maritime DC microgrids, offering stable voltage regulation, effective load prioritization, and resilient operation of critical loads.

Heavy-duty vehicles (HDVs), while accounting for only 3-7% of total vehicles on German roads, were responsible for 25-27% of CO2 emissions from road transport sector in 2019, a share that continues to rise. Germany's climate action program sets a target to electrify 30% of HDVs by 2030, for which battery electric trucks (BETs) are a promising solution. However, their widespread adoption, particularly for battery HDVs, requires the development of a reliable public fast-charging infrastructure. Despite the growing relevance of electric HDVs, there is limited research on the public charging infrastructure for HDVs along the Trans-European Transport Network (TEN-T). Existing studies rarely incorporate recent government policies and spatial constraints into their optimization models. To address this research gap, a spatial and temporal public charging infrastructure model is developed to forecast the energy demand and identify optimal locations for placing charging infrastructure for freight transportation. In addition, a simple economic analysis of public charging stations is done to calculate the total system costs. The model distinguishes between distribution and long-haul trucks based on driving cycles and integrates the European Transport policy Information System (ETISplus) freight dataset at NUTS-3 level. The model considers two adoption scenarios: a gradual scenario, representing slow market adoption of BETs, and an accelerated scenario, reflecting strong and fast adoption driven by government policy support and rapid technological advancements. The model estimates future energy demand and infrastructure requirements under both scenarios until 2050. Results indicate that energy demand from BETs could reach 62 TWh by 2050, necessitating the deployment of over 3850 public fast-charging ports in the accelerated scenario. Based on model outcomes, key recommendations for spatial planning of public EV charging infrastructure include: (1) initially prioritizing charger deployment in highdemand areas with significant truck traffic; (2) restructuring the existing truck parking bays by replacing conventional chargers rather than constructing entirely new stations; and (3) Placing chargers near driver amenities to facilitate mandatory breaks while parallelly charging. The findings underscore the importance of infrastructure planning and resource policy to support the electrification of Germany's freight sector.