Simulation, Optimization andTechno-Economic Evaluation of a Photovoltaic HydrogenFuel Cell Hybrid Power System

Rapidly increasing energy demand along with environmental concerns are among the major drivers for adoption of renewable and low-carbon energy technologies [۱]. A Hybrid Power System (HPS) consists of two or more power sources (such as PV-Wind, PV-fuel cell, etc.) and is considered a reliable power supply solution that can mitigate the intermittency of output power from renewable energy sources as well as the need for large energy storage systems [۲].Hydrogen which is primarily produced by the electrolysis of water as an environmentally friendly and clean process, is a sustainable energy carrier that canbe efficientlyconverted into electric power and as a result is used as an energy storage solution for intermittent renewable energy sources [۳]. In this study a hybrid PV-fuel cell system is simulated and optimized for a residential building located in the city of Kashanusing Homer Pro software. In addition, an economic evaluation of the system is presented.Panel (a) of Figure ۱ shows a schematic diagram of the PV-hydrogen fuel cell HPS and panel (b) depicts the basic structure of the hydrogen fuel cell.The proposed HPS is based on hydrogen technology and consists of polymer electrolyte membrane (PEM) fuel cell, a hydrogen storage unit (tanks) and hydrogen production unit (electrolyzer) which operates by excess electric power from the PV system. The HPS is simulated and optimized by minimizing the net present cost of the system The optimal HPS architecture for meeting the electrical load of the residential building with thepeak load of ۷۴.۱ KWh and average daily load of ۷۴۹.۵۱ KWh/day is as follows: ۵۷۷ kW of PVand ۱۰۰ kW of fuel cell capacity. Power output from the fuel cell, rated at ۱۰۰ kW using storedhydrogen as fuel, is۲۵۳,۸۱۳ kWh/yr.In addition the total hydrogen production of the electrolyzer is ۱۵۲۲۳ Kg/yr. Results of the financial evaluation of the HPS showed that the levelized cost ofelectricity for the system is about ۰.۵۱ $/KWh. Sensitivity analysis showed the system LCOEissensitive to variations in the discount rate.This paper introducesand simulates anoptimized PV-FC hybrid power system which can be eitherconnected to the grid or operate off-grid. This system uses a hydrogen fuel cell storage to produceelectricity using excess solar energy. Although PV-FC HPS has higher initial capital, it has about۸۰% and ۱۲۰% lower operating cost relative to PV-diesel-battery and diesel generators respectively and LCOE of PV-FC is lower than PV-diesel-battery and diesel generators. Inaddition, utilizing the proposed PV-FC HPS can lead to an estimated reduction of about ۰.۱۵۶ tonof CO۲ per year when operating off-grid. Although the initial investment cost for PV-FC is high,lower LCOE and zero CO۲ emission increase the economic viability of the system. Rapiddevelopment of fuel cell technologies will make them more cost efficient to be utilized alongsideintermittent renewable energy sources in hybrid power systems to supply clean, sustainable andzero carbon power.