Exergy and Thermoeconomic Analyses of Solar Aided Thermal Power Plants with Storage-A Review
Ever increasing energy demand, spiralling fuel prices dwindling resources and emissions foot print of fossil fuel based power generation has forced the world to increase the share of renewable energy based power generation. Out of all renewable energy sources (RES), solar has emerged as a viable option for addressing several challenges being faced by the power generation industry currently. Solar PV and solar thermal are the two options for solar based power generation. Although Solar PV provides excellent energy solutions for small scale grid and off grid power generation, it is not suitable for large scale power generation. Now within solar thermal, solar alone power generation has not gained popularity due to high capital costs and poor thermal efficiency but solar integration with existing/new power plants (both coal fired thermal and gas fired combined cycle) popularly known as solar aided power generation has been widely accepted by several researchers. This technology has been widely in use in countries like U.S, Spain, Egypt, Morocco, Algeria, Iran and Mexico (NREL web site).Due to lower capital costs and better solar to electricity conversion efficiencies, solar aided thermal power plants have surpassed solar alone power plants. Solar energy can be integrated in a coal fired plant either for steam generation or for feed water heating. In a combined cycle plant, solar energy can be integrated either in the Brayton cycle or in the bottoming Rankine cycle. This chapter discusses in detail, various integration techniques, the application of exergy, economic and thermo economic principles in analysing these integrated cycles. Detailed economic analysis has been reviewed on the integrated cycles to ascertain their techno economic viability. The levelised cost of electricity generation (LCoE) and simple payback period have also been predicted for both the reference and integrated plants.
