Energy, exergy, economic and environmental (4E) analyses of 100 MW concentrated solar power plant in an arid region of Pakistan

Concentrated Solar Power (CSP) technology uses a heliostat field to focus direct normal irradiance onto a central receiver, heating a fluid that generates steam for a conventional turbine–generator set. In this study, we evaluate the technical, economic and environmental performance of a 100 MW solar power tower plant at Islamkot in Pakistan's Thar region, chosen for its high annual Direct Normal Irradiance (DNI) of 1600–1900 kWh/m2, level terrain and proximity to grid and transport infrastructure. Thermodynamic analysis based on the Rankine cycle coupled with NREL's System Advisor Model predicts an annual electricity output of approximately 277.4 million kWh and a levelized cost of electricity of $0.0916 per kWh over a 30-year lifespan. Exergy evaluation indicates an overall efficiency of 22.9 percent, decreasing to 20.6 percent when auxiliary parasitic loads are accounted. Financial metrics show a net present value of $623.7 million, a discounted payback period of 9.4 years and a return on investment of 1.53 times. Replacing an equivalent conventional thermal plant yields an annual reduction of nearly 115,000 tons of CO2, which is approximately 82 % percent decrease in lifecycle emissions, demonstrating substantial environmental benefit.