Comparative Analysis of On-Board Methane and Methanol Reforming Systems Combined with HT-PEM Fuel Cell and CO2 Capture/Liquefaction System for Hydrogen Fueled Ship Application

Abstract

This study performs energetic and exergetic comparisons between the steam methane reforming and steam methanol reforming technologies combined with HT-PEMFC and a carbon capture/liquefaction system for use in hydrogen-fueled ships. The required space for the primary fuel and captured/liquefied CO2 and the fuel cost have also been investigated to find the more advantageous system for ship application. For the comparison, the steam methane reforming-based system fed by LNG and the steam methanol reforming-based system fed by methanol have been modeled in an Aspen HYSYS environment. All the simulations have been conducted at a fixed Wnet, electrical (475 kW) to meet the average shaft power of the reference ship. Results show that at the base condition, the energy and exergy efficiencies of the methanol-based system are 7.99% and 1.89% higher than those of the methane-based system, respectively. The cogeneration efficiency of the methane-based system is 7.13% higher than that of the methanol-based system. The comparison of space for fuel and CO2 storage reveals that the methanol-based system requires a space 1.1 times larger than that of the methane-based system for the total voyage time, although the methanol-based system has higher electrical efficiency. In addition, the methanol-based system has a fuel cost 2.2 times higher than that of the methane-based system to generate 475 kW net of electricity for the total voyage time.

Emission Analysis of LNG Fuelled Molten Carbonate Fuel Cell System for a Chemical Tanker Ship: A Case Study

“…In this study, emissions are calculated according to main engine fuel consumption. Despite the specific fuel oil consumption (SFOC) and ship emissions depend on the engine load, generally, the total system load is smaller than the main engine power capacity because usually ships sail between 60-80% engine load (Lee et al, 2020;Berstad, et al, 2013). Therefore, the specific fuel consumption is directly related to engine load.…”

“…From this perspective, IMO has introduced the Energy Efficiency Design Index (EEDI), the Ship Energy Efficiency Management Plan (SEEMP), and Energy Efficiency Operational Indicator (EEOI) in MARPOL Annex VI in 2013 (IMO, 2011). To achieve emission reduction from ships, and to stay under limitations, various options must be well analysed and introduced such as increasing engine efficiency with a more efficient energy management plan (Uyanık et al, 2020), load, road, and speed optimization (Psaraftis and Kontovas, 2014), slow steaming (Dere and Deniz, 2020), alternative marine fuels (Deniz and Zincir, 2016;Hansson et al, 2019), auxiliary solar PV systems (Karatuğ and Durmuşoğlu, 2020), hybrid and electric propulsion systems (Bennabi et al, 2016) or exhaust gas cleaning systems (Lee et al, 2020;Zhu et al, 2018). However, according to exhaust gas contents, treatment technology varies, and therewithal to reduce NOx emission, there are Exhaust Gas Recirculation (EGR) and Selective Catalytic Reduction after treatment (SCR) (Raptotasios et al, 2015).…”

Thermal Evaluation of a Novel Integrated System Based on Solid Oxide Fuel Cells and Combined Heat and Power Production Using Ammonia as Fuel

“…The usage of ammonia can be determined in terms of the actual provide and consumption of the ammonia, or its hydrogen counterpart, such that [21,22,24,29]…”

“…1.4 SOFC efficiency 56.8% Total power required by propulsion plant of target vessel at maximum load [29] 3800 kW…”

Simulation Analysis of a Methanol Fueled Marine Engine for the Ship Decarbonization Assessment

“…(FC) [11,12]. In particular, FC systems with onboard methanol reformers are being deployed in pilot projects in the United States, Europe, and China [13,14]. However, in applications where a higher power density is required, ICEs still represent the most suitable solution.…”