No abstract

In this study, two solid oxide fuel cell (SOFC) hybrid systems (anode-supported model (ASM) and electrolyte-supported model (ESM)) is developed in matlab® and compared. The hybrid system model is considered to investigate the impacts of various operating parameters such as SOFC operating temperature and steam/carbon ratio on power production and performance of the hybrid system where it is projected that results can be utilized as guidelines for optimal hybrid system operation. According to the findings, a maximum 695 kW power is produced at 750 °C operating temperature for the anode-supported model, whereas 627 kW power is produced at 1000 °C for the electrolyte-supported model. The highest electrical efficiencies for the anode-supported model and the electrolyte-supported model are 64.6% and 58.3%, respectively. Besides, the lower value of the steam to carbon ratio is favorable for increased power output from the fuel cell and consequently a high SOFC efficiency.

Enhancing the sustainability and diversification of Iraq’s electricity system is a strategic objective. Achieving this goal depends critically on increasing the use of renewable energy sources (RESs). The significance of developing solar-powered technologies becomes essential at this point. Iraq, similar to other places with high average direct normal irradiation, is a good location for concentrated solar thermal power (CSP) technology. This study aims to recover the waste heat from the gas turbine cycle (GTC) in the Al-Qayara power plant in Iraq and integrate it with a solar power tower. A thermoeconomic analysis has been done to support the installation of an integrated solar combined cycle (ISCC), which uses concentrated solar tower technology. The results indicate that the examined power plant has a total capacity of 561.5 MW, of which 130.4 MW is due to the waste heat recovery of G.T.s, and 68 MW. is from CSP. Due to the waste heat recovery of GTC, the thermal and exergy efficiencies increase by 10.99 and 10.61%, respectively, and the overall unit cost of production is 11.43 USD/MWh. For ISCC, the thermal and exergy efficiencies increase by 17.96 and 17.34%, respectively, and the overall unit cost of production is 12.39 USD/MWh. The integrated solar combined cycle’s lowest monthly capacity was about 539 MW in September, while its highest monthly capacity was approximately 574.6 MW in April.

The response surface methodology (RSM) is used in the present research together with a group of variables that have an effect on engine performance and output exhaust from the combustion process. Therefore, the purpose of the current paper is to get efficiency best by using biodiesel fuel and comparative with normal fuel. The variables under consideration include biodiesel ratio, engine load, and injection pressure. The experiments were performed with different engine speeds (1500, 2000, and 2500 rpm) and with different torques (4, 5, 5, 7, and 8 N.m). The biodiesel ratio (at 10%, 20%, and 30%) affects engine performance, power, specific fuel consumption, and mean effective pressure. The comparison is performed in the previous variables according to the gas ratio of the output exhaust (NOX, CO2, CO, HC, and smoke). The experimental work shows the center composite design approach of the response surface methodology. To get the best performance from the engine, the optimal values for the engine factors are 50% per volume, an engine speed of 2500 rpm, and an engine torque of 5.9744 Nm. The optimal engine performance responses depending on these optimal factors have been Power (KW) 2.36665, BMEB (bar) 3.6465, BSFC (g/kWh) 338.131. The exhaust released was 1.7808 (g/kWh). 273.985 (g/kWh) BSCO2, 0.0436773 (g/kWh) BSCO BSHC, NOX (2.48637 g/kWh), and 3.43418 g/kWh smoke.

This article presents a steady-state thermodynamic model of a solid oxide fuel cell/gas turbine hybrid cycle which developed by using a simulation software, MATLAB®. The hybrid model integrates a zero-dimensional level SOFC model with gas turbine. The hybrid system was used to study the effects of some operation parameter such as SOFC operating temperature, and current density on the specific work output, electrical efficiency, and exergy efficiency of a generic hybrid cycle. The results show that if the SOFC operating temperature, the power output, electrical efficiency, and exergy efficiency increase. The electrical efficiency of the hybrid system increase from 62% to 68%, and the exergy efficiency of the hybrid system increases from 60% to 66% when the operation temperature increases from 600°C to 750°C at a current density of 6000 A/cm2. On the other hand, the system efficiency and exergy decreases with an increase in the current density.