Reversible Solid Oxide Fuel Cell Connected to Solar PV/T System: Cell Electrochemical Modelling and Analysis

Abstract

Abstract. In this paper, a novel power generation cum storage system employing reversible solid oxide fuel cell (RSOFC) has been proposed and modelled. The RSOFC is integrated with solar PV/T system. Here only the electrochemical modelling of the fuel cell unit has been presented and analysed thermodynamically. The RSOFC unit operates in steam electrolyser mode (during day time) as well as in fuel cell mode (during night time). The electrochemical model has been developed by using Engineering Equation Solver. Performance of RSOFC unit has been investigated under varying operating parameters viz. applied current density and operating cell temperature. For electrolyser mode of operation maximum efficiency is found to be 93% at a current density (J) 8000 A/m 2 and at cell temperature (Tcell) 1273K. Maximum efficiency during fuel cell mode of operation is found to be 77% at cell temperature 1073K and at current density 500 A/m 2 . IntroductionAccording to IEA report [1], fossil fuels contribute a major share of electricity production till now. Fossil based power plants are the major emitter of greenhouse gases. Therefore, designing advanced power generation system employing renewable energy sources is essential to neutralize greenhouse gas emissions. In that context, fuel cell technology has a potential to provide a clean and sustainable form of energy without emitting any polluting agents. Reversible solid oxide fuel cell (RSOFC) is a promising new technology which can operate in solid oxide fuel cell (SOFC) mode as well as in solid oxide steam electrolyser (SOSE) mode. RSOFC generally operates at a very high temperature (873-1273 K). Thus, it requires a high temperature heat source to preheat the incoming feed (H2 and air in SOFC mode of operation, H2O in SOSE mode of operation).Akikur et al.[2] proposed a solar powered RSOFC based cogeneration system. The overall efficiency of the system is found to be 20% and 23% in the solar-SOSE mode and the solar-SOFC mode respectively. Wendel et al. [3] studied the performance of an intermediate temperature RSOFC and found that efficiency, more than 70% can be achieved at intermediate stack temperature (680 0 C). Kazempoor et al. [4] proposed a RSOFC based energy storage system in which they investigated the effect of operating parameters viz. temperature, gas composition and fuel utilization on cell voltage, at varying current densities. Visitdumrongkul et al. [5] investigated the performance of SOSE integrated system for H2 production. The effect of operating parameters viz. oxygen to carbon ratio, operating

Recent Development in Reversible Solid Oxide Fuel Cells: Theory, Integration and Prospective

“…In the context of research on solar energy coupled with RSOC systems, Mishra et al [131] have proposed an innovative power generation and energy storage solution. This approach integrates RSOC with solar PV/T, allowing the RSOC device to operate in an electrolysis mode during the day and in a fuel cell mode at night.…”