Energy, exergy, and economic analyses of integration of heliostat solar receiver to gas and air bottom cycles

Abstract

In this paper, the energy, exergy, and economic analysis of a novel integrated power plant is investigated. The novel power plant is integrated by using the heliostat solar receiver, the heliostat solr reciever is integrated with many types of traditional power plants such as the gas turbine cycle, air-bottoming cycle, and absorption refrigeration system. Also, the integration of the heliostat solar receiver to heat the exhaust air from the compressor to reduce the natural gas consumption within the gas cycle has been investigated. For the proposed configurations, energy, exergy, and economic analysis for Tehran, Iran (35.689°N, 51.5°E) has been conducted. The model has been validated using previously published results of other authors. Since the investigated configurations are innovative and to the best of our knowledge a similar whole system does not exist in the literature, each cycle has been validated separately. Results and comparisons are given for six different combinations: gas cycle, gas cycle with air bottoming cycle, and gas cycle with air bottoming cycle and absorption refrigeration system. The previously mentioned cycles are analyzed again but this time with integrating them with heliostat solr reciever. The comparisons study is conducted in terms of monthly average energy efficiency, monthly average exergy efficiency, annual average energy efficiency, annual average exergy efficiency, net present value, simple payback period, payback period, and internal rate of return. Results show that adding the heliostat solr reciever to the different cycles minimizes the fossil fuel consumption and enhance energy performance very significantly, for example the energy and exergy efficiencies are increased from 44% up to 69%. Regarding some economic indicators such as the internal rate of return parameter, the results show that the highest internal rate of return belongs to the combination of the gas cycle with air bottoming cycle and absorption refrigeration system with the value of 0.48 and the combination of the gas cycle combined with heliostat solar receiver has the lowest value of internal rate of return of 0.16. As a result of the reduction in fuel consumption savings and other economic indicators are achieved in addition to better environment impact. Finally, the integration of heliostat solar receiver in power cycles shows many advantages mainly in hot areas where solar radiation is high.