The Exergy Costs of Electrical Power, Cooling, and Waste Heat from a Hybrid System Based on a Solid Oxide Fuel Cell and an Absorption Refrigeration System

Abstract

This paper applies the Exergy Cost Theory (ECT) to a hybrid system based on a 500 kWe solid oxide fuel cell (SOFC) stack and on a vapor-absorption refrigeration (VAR) system. To achieve this, a model comprised of chemical, electrochemical, thermodynamic, and thermoeconomic equations is developed using the software, Engineering Equation Solver (EES). The model is validated against previous works. This approach enables the unit exergy costs (electricity, cooling, and residues) to be computed by a productive structure defined by components, resources, products, and residues. Most importantly, it allows us to know the contribution of the environment and of the residues to the unit exergy cost of the product of the components. Finally, the simulation of different scenarios makes it possible to analyze the impact of stack current density, fuel use, temperature across the stack, and anode gas recirculation on the unit exergy costs of electrical power, cooling, and residues.

A Three-Dimensional Microstructure-Scale Simulation of a Solid Oxide Fuel Cell Anode—The Analysis of Stack Performance Enhancement After a Long-Term Operation

“…The current values were set in a range of 0 A to 18 A. Given the total active cell area of 6 cm × 8 cm = 48 cm 2 = 0.0048 m 2 , this translates to current densities of 0-3750 A m −2 . The stack operated at temperatures in the range of 650-800 • C. All of the experimental results referred to in this section have been obtained from the aforementioned experiment.…”

“…Constant temperatures are assumed within the computational domain, and the transport coefficients are approximated to be constant in relation to the model variables. The conductivity coefficients for the Nickel and Yttria-stabilized Zirconia phases in a Ni-YSZ cermet are computed using empirical relations (see Equations (2) and (3)) based on the experimental data by Anselmi-Tamburini et al [30] and Bessette et al [31]:…”

“…Solid oxide fuel cells (SOFCs) are the type of fuel cells, in which the electrolyte is composed of ceramic material, and the electrodes are made of porous ceramic-metal composite. Due to their high-efficiency, low environmental impact, and a wide variety of potential applications, SOFCs continue to attract considerable interest of the scientific community [1][2][3]. The porous, composite electrode of an SOFC is characterized by a complex microstructure, which affects the electrochemical phenomena.…”

Exergoeconomic analysis of an industrial beverage mixer system

“…Therefore, we used TAESS and exergoeconomic analysis to evaluate the system. Developed by the Centre of Research for Energy Resources and Consumption in conjunction with the Department of Mechanical Engineering at the University of Zaragoza, Spain [ 40 , 41 ], TAESS has been used by various researchers for exergoeconomic applications [ 11 , 42 , 43 ]. It is based on the principle of exergetic cost theory (ECT) in the exergoeconomic analysis.…”

Energy-Saving Strategies and their Energy Analysis and Exergy Analysis for In Situ Thermal Remediation System of Polluted-Soil

“…The energy analysis is focused on the quantity of energy and the exergy analysis is focused on the quality of energy. Numerous studies have used these methods, such as the novel combined cooling, heating, and power (CCHP) system [38,39], ground source heat pumps [40], and exhaust waste heat recovery systems [41] and so on. Energy plays an important role in the history of human development [30].…”