Thermodynamic analysis of a combined gas turbine power plant with a solid oxide fuel cell for marine applications

Abstract

Strong restrictions on emissions from marine power plants (particularly SO x , NO x ) will probably be adopted in the near future. In this paper, a combined solid oxide fuel cell (SOFC) and gas turbine fuelled by natural gas is proposed as an attractive option to limit the environmental impact of the marine sector. It includes a study of a heatrecovery system for 18 MW SOFC fuelled by natural gas, to provide the electric power demand onboard commercial vessels. Feasible heat-recovery systems are investigated, taking into account different operating conditions of the combined system. Two types of SOFC are considered, tubular and planar SOFCs, operated with either natural gas or hydrogen fuels. This paper includes a detailed thermodynamic analysis for the combined system. Mass and energy balances are performed, not only for the whole plant but also for each individual component, in order to evaluate the thermal efficiency of the combined cycle. In addition, the effect of using natural gas as a fuel on the fuel cell voltage and performance is investigated. It is found that a high overall efficiency approaching 70% may be achieved with an optimum configuration using SOFC system under pressure. The hybrid system would also reduce emissions, fuel consumption, and improve the total system efficiency.

Fuel utilization effects on system efficiency in solid oxide fuel cell gas turbine hybrid systems

“…Solid oxide fuel cell (SOFC) -gas turbine (GT) hybrids show top electrical efficiencies around 70%, the highest of any power-cycle [1]. Efficiency and the types of fuel used in fuel-cells (e.g., syngas, reformed methane) combine to produce lower emissions than other fossil-powered technologies [2]. With this hybrid, high efficiency can be reached without the need for water cooling; therefore, water consumption per MW e is lower than other technologies which approach the 70% efficiency mark.…”

CFD Modeling of Syngas Combustion and Emissions for Marine Gas Turbine Applications

“…[35]. Consequently, the syngas fuel satisfies the new international NO x emission regulations, as the natural gas satisfies new IMO regulations on NO x emission, according to Lloyd's Register options for the compliance with new IMO regulations [36,37]. Finally, Fig.…”

Optimization of the Performance of Marine Diesel Engines to Minimize the Formation of SOx Emissions

“…The hydrogen and the NG are receiving considerable attention in shipping due to their availability and their low cost, and they are free of carbon and sulfuric materials (El-Gohary 2012). El-Gohary and Seddiek (2013) presented the usage of both hydrogen and NG as alternative fuels to diesel oil for a marine gas turbine which lead to 100% reductions in SO x emissions and particulate matter (PM) and 92% reduction in NO x emissions and 25% reduction in carbon dioxide (CO 2 ) as compared with diesel fuel (Welaya et al 2013b;El-Gohary et al 2015). Hydrogen is also used to convert the chemical energy into electricity in the fuel cell technology (Welaya et al 2011;Welaya et al 2013a;Villalba-Herreros et al 2017).…”