Optimizing gas-steam combined cycle with solar energy integration: A thermodynamic and economic analysis

Abstract

The depletion of energy reserves worldwide has driven studies on optimizing existing power systems. Among all renewable clean energies, solar energy might offer a potential solution for gas-steam combined cycle systems widely used in power generation. The current study explores the thermodynamic and economic benefits resulting from the integration of solar energy into a combined cycle in an Integrated Solar Combined Cycle system. Based on the first law of thermodynamics, a thermodynamic model was developed in the present work, and simulations were run employing EBSILON Professional software. In this work, the ISCC system is compared to a traditional GTCC system: variations produced by the most relevant variables have been analyzed, namely DNI and ambient temperature. The results highlight that, with an input of natural gas of 10 kg/s, the ISCC system gives a cycle thermal efficiency of 44.1%, whereas that from GTCC is 39.8%. Further, ISCC decreases natural gas consumption by 2.638 kg/s at identical output power. Eventually, solar energy integration results in increased system efficiency and reduced fuel consumption, promising some encouraging economic benefits. Thus, ISCC systems are positioned as feasible options for future energy requirements.