Project Summary
This project will develop and validate a modular hydrogen fuel cell auxiliary power unit (APU) designed to decarbonise support systems onboard small-to-medium maritime vessels. By replacing conventional diesel generators used for auxiliary loads such as lighting, navigation, refrigeration and hoteling functions, the proposed hydrogen-based system aims to significantly reduce CO?, NO?, and particulate emissions in port and near-shore operations, which are key hotspots for maritime pollution. The project combines advanced system-level modelling with lab-scale validation using Coventry University’s existing fuel cell platform, enabling accurate simulation of performance, cost and emissions impact across a range of vessel types and duty profiles. Outputs will include validated models, a comparative techno-economic and environmental performance assessment against diesel and battery-based alternatives, and a scale-up roadmap for real-world adoption. The study supports TRIG’s maritime decarbonisation priority by targeting retrofit-friendly, low-emission APU technology that can deliver tangible improvements in operational sustainability, particularly in ports and emission control zones. This early-stage proof of concept will not only strengthen evidence for hydrogen fuel cell integration in marine applications, but also inform policy, regulatory and industrial stakeholders about deployment potential and infrastructure needs; positioning the UK maritime sector for clean auxiliary power transition and improved air quality outcomes.
Project Achievements
Developed a MATLAB/Simulink (Thermolib) system model for a modular PEM fuel-cell APU for maritime auxiliary loads and calibrated it using laboratory experimental data. Produced validated performance and efficiency maps (kWh/kg H₂), quantified cell-to-cell voltage spread to define safe operating limits, and translated results into modular sizing guidance for representative berth-demand scenarios. Completed screening techno-economic and lifecycle assessments to identify key cost and carbon drivers (hydrogen pathway, BoP parasitics, utilisation). Outputs are being prepared for journal publication and are informing follow-on consortia for CMDC and Horizon Europe demonstrator bids.
Conclusions
A modular hydrogen fuel-cell APU is technically feasible for in-port/near-shore decarbonisation when designed around validated stack performance. Experimental results confirm module capability and show that cell-voltage dispersion increases markedly at high current density, so continuous operation should be constrained by minimum-cell-voltage/spread limits rather than power alone. System-level screening indicates strong CO₂e reduction potential with low-carbon hydrogen, while economics are dominated by hydrogen price, BoP efficiency and utilisation. The project delivered a validated model-and-data evidence base to support scale-up decisions, hybridisation (fuel cell + battery) and partner engagement for demonstrators.
Next Steps
Next we will (1) refine the BoP representation with component maps, (2) validate transient behaviour and degradation-aware operation, and (3) develop a modular multi-stack + battery architecture for peak shaving and reliability. We will package the concept for retrofit (space/weight, ventilation, safety case/HAZID/HAZOP, class requirements) and target a shore-based integrated prototype trial (TRL4) within ~18-24 months, followed by a port-side/vessel-adjacent pilot (TRL5). We are forming a consortium with TRIG cohort members, integrators and end-users (ports/operators) and preparing CMDC and Horizon Europe proposals to fund prototype build, field validation and commercialisation planning.
