A transient study on a solar-assisted combined gas power cycle for sustainable multi-generation in hot and cold climates: Case studies of Dubai and Toronto

Efficiently managing heat losses continues to be a prominent obstacle within gas-fired power plants. The discharge of high-temperature gases from turbines and the considerable pressure generated by compressors present compelling opportunities for augmenting both power generation and overall efficiency. The present study analyzes a gas-fired power plant with two additional Rankine cycles and a concentrated solar power system to enhance efficiency and output power. Clean power generation and distilled water were the outputs of the proposed system. This study also sought to reduce greenhouse gas (GHG) emissions by using solar energy and diminishing the consumption of fossil fuels (CH₄) in the combustion chamber. The proposed system was implemented in hot and cold climates. The Brayton cycle of the system was validated through data of a real-life power cycle on the southern coasts of Iran. Furthermore, a transient evaluation was conducted to explore the effects of climatic parameters on the power and desalination system. The contributions of solar irradiance, wind speed, and ambient temperature to the proposed system in a hot climate (Dubai, UAE) and a cold climate (Toronto, Canada) were evaluated. It was found that gas turbine efficiency, compression ratio, and gas turbine input temperature had the greatest effects on the system. Exergy analysis revealed that the combustion chamber, heliostats, the solar receiver, the multi-effect distillation (MED) unit, gas turbine 1, and the thermoelectric generator accounted for the largest portion of the exergy destruction. The case study indicated that the system would work best in climates like Toronto. The findings can be useful to investors and governments in such climates. The proposed system demonstrates its adaptability to regions sharing a climate resembling that of Toronto, making it a viable solution for a wide range of geographical areas. The design and functionality of the system have been meticulously crafted to accommodate the specific environmental conditions present in Toronto and its comparable regions. Gas-fired power plants across numerous countries widely employ the Brayton cycle as their primary operational framework. In this context, the proposed system presents a compelling opportunity to unlock valuable outcomes and advancements.