# Analysis of Hybrid Ship Machinery System with Proton Exchange Membrane Fuel Cells and Battery Pack
## 1 Introduction
analyzed several issues, such as the new technology and characteristics of different fuel cell systems as well as the international maritime organization rules and policies for hydrogen system applications in the marine industry [9]. In the paper [10], a fuel cell marine power systems model with real-time capabilities was developed and can be implemented for researching performance to obtain an effective system and determining the balance of plant, control, and optimization possibility. To enhance shipping fuel efficiency in an energy management system, optimization for day-ahead power generation plans and dynamically adjusted power splitting were presented in [11]. A hybrid marine propulsion architecture with advanced control strategies can reduce fuel consumption up to 35% while improving noise, maintainability, maneuverability, and comfort [12]. [PERSON] [13] conducted an analysis of the environmental impact and cost of a proton exchange membrane fuel cell (PEMFC) system for use in fuel cell vehicles in comparison with battery electric and internal combustion engine vehicles. When hydrogen is generated from renewable electricity, fuel cell cars reduce greenhouse gas emissions by 50% compared to gasoline-powered cars. A hybrid marine propulsion system with a heat engine in combination with a battery for electromotors was analyzed in a real load application, and the performance of the components was evaluated [14]. One study proposed and analyzed a hybrid propulsion system for ships that utilizes both the electric energy and thermal energy generated by fuel cells. The proposed hybrid propulsion system can increase energy efficiency by 22.5% [15]. The PEM fuel cell-battery hybrid system was developed and integrated with Li-ion batteries to supply electric power to the waterjet propulsion system of the 20 m tourist boat and successfully operated at 6-8 knots [16]. A hybrid propulsion system consisting of hydrogen wind and solar energy was also analyzed. The results shows that wind power can cover up to 27%, solar power up to 1%, and hydrogen fuel cell up to 100% of the total required power for propulsion [17]. A solid oxide fuel cell (SOFC) for a crude oil tanker was investigated, and the results showed that CO2 emissions in the SOFC hybrid system were up to 8.8% lower than in the traditional large vessel [8]. A fundamental platform for exploring a hybrid energy system integrated with fuel cell was given in one study, with emphasis on system optimization and energy management strategies [18]. One control strategy of a ship with hybrid power consisting of a 4-stroke diesel generator, solar panels, and battery packs was simulated, and the energy efficiency and emissions were evaluated. The results of the developed hybrid micro-grid system control system showed that it can significantly reduce CO2 emission and energy cost [19]. From the economic perspective, this system is still expensive. The estimated cost for a fuel cell-battery hybrid propulsion system for repowering a catamaran (20 m long) consisting of (DC) a redundant electric power plant (300 kW) and propulsion system, energy storage system, and marine fuel cell modules is approximately EUR 1,200,000. America's first hydrogen-powered catamaran, Switch Maritime, aims to start operations early next year in San Francisco and is powered with PEMFC-s with 360 kW of power; it has 242 kg of hydrogen storage tanks and a 600 kW electric propulsion system with speed up to 15 knots and cost of USD 10 million. The high cost of hydrogen, safety considerations, and the supply infrastructure are problems for the wide adoption of fuel cell systems [20]. \"Handbook for Hydrogen-fueled Vessels\", written by DNV and other companies, deals with safety issues for hydrogen as ship fuel [21]. This paper offers detailed insight into the novel hybrid propulsion systems that incorporate a system with a PEMFC stack with battery pack at known load cycles.