Analysis of solid oxide fuel cell hybrid power system in marine application for CO2 reduction

The usefulness of a solid oxide fuel cell (SOFC) for a large vessel is evaluated by estimating the amount of CO2 emitted by a crude oil tanker. Conventional and two SOFC hybrid power generation systems are proposed and analyzed. The traditional system consists of five generators and a steam boiler, whereas two SOFC hybrid systems are made up of five smaller generators with additional SOFC power and a steam boiler. The performance of the SOFC is calculated through a zero-dimensional model developed, including electrochemical stack model. The CO2 emission of the SOFC hybrid system is estimated depending on the SOFC capacity, 2.5 MW and 5.0 MW. CO2 emissions in the SOFC hybrid system are 5.4% ∼8.8% lower than in the traditional structure for one round trip sail. The reduction of CO2 comes from two factors; the high efficiency of SOFC and the operations of DF generators at a relatively high load rate. The SOFC hybrid system can be an eco-friendly technology to reduce the CO2 emissions of the large ships.