EXERGY ANALYSIS OF REVERSIBLE SOFC COUPLED WITH ORGANIC RANKINE CYCLE AND HYDROGEN STORAGE FOR RENEWABLE ENERGY STORAGE

Abstract

A novel renewable energy storage system based on reversible solid oxide fuel cell (SOFC) with integrated organic Rankine cycle (ORC), metal hydride hydrogen storage (MHHS) and absorption refrigeration cycle are proposed in the present study. The system utilizes the waste heat generated from the SOFC unit into the ORC evaporator to produce power using the turbine. After that, the rejected heat is being used for heating application and produces a cooling effect by implementing the single-effect absorption chiller. A part of high-quality exhaust heat from SOFC is transferred to the MHHS for the desorption process to facilitate the release of hydrogen. Exergy analysis of the trigeneration system and evaluation of the exergy destruction rates of system components is carried out. Furthermore, a detailed parametric study is conducted to study the influence of critical parameters such as current density, SOFC temperature and turbine inlet pressure on exergy efficiency and exergy destruction rates. It has been observed that the maximum value of trigeneration energetic efficiency of 74% is obtained at SOFC temperature of 800°C and current density of 0.8 A/cm2. Moreover, maximum net electrical exergy efficiency is 67.39%, maximum heating exergy efficiency is 73.1%, maximum cooling exergy efficiency is 66.48%, and maximum ORC exergy efficiency obtained is 16.63%. © 2022 Proceedings of WHEC 2022 - 23rd World Hydrogen Energy Conference: Bridging Continents by H2. All rights reserved.