Exergy and thermoeconomic analyses of 500Â MWe sub critical thermal power plant with solar aided feed water heating

In this paper, an attempt has been made to integrate solar aided feed water heating with a 500 MWe sub critical coal fired thermal power plant. Complete bleed steam substitution in high pressure heaters (HPH) has been attained by placing a feed water heat exchanger (FWHE) in parallel to the HPH group for solar aided feed water heating. Exergy and thermo economic analyses have been performed on both reference 500 MWe and conceptual solar aided 500 MWe thermal power plants. The exergy analysis has revealed that the solar field followed by boiler have the maximum exergy destruction ratios of 78.90% and 56.52% respectively. The corresponding second law efficiencies of solar field and boiler are 21.10% and 43.48% respectively. Thermoeconomic analysis has been performed on both the plants by developing physical and productive structures for them. A set of linear equations have been developed and solved for finding the cost rates of different product streams.