Sensitivity analysis of energy, exergy, and environmental models for a combined cooling, heating, and power system at different operating conditions of proton exchange membrane fuel cell

Abstract

In this research article, for recovering the waste heat of the proton exchange membrane (PEM) fuel cell, a combined cooling heating and power (CCHP) system with a new arrangement is proposed. The main system components are a PEM, an absorption chiller, an auxiliary boiler, and hydrogen and heat storage tanks. The electrochemical model of PEM is presented for evaluating the power and heat of the fuel cell. Also, energy and exergy efficiencies and fuel energy saving ratio of the CCHP system are evaluated by the steady‐state thermodynamic model, and for the first time, the impacts of critical operating parameters of PEM such as current density, operating pressure, and temperature on the annual carbon dioxide (CO2) emission reduction and annual CO2 tax reduction as well as fuel saving are studied. The results show that the proposed CCHP system's energy efficiency is evaluated at about 66%. With the increase in temperature of PEM, the exergy efficiency reaches 37%. In addition, using this system can reduce CO2 emissions by 191 ton per year. Also, this system can reduce the tax cost of carbon dioxide emissions by about $ 5700 per year.

Effect of Diesel-engine Operating Conditions on Performance of Waste Heat Recovery Cycles: A 4E Analysis

“…To calculate the Annual CO2 Emission Reduction (ACO2ER) for the proposed system, first, CO2 emission rates of the proposed system has been calculated as follows (21,22):…”