Water, Energy, and Environment NEXUS Assessment in Combined Thermal-Solar Power Plant (Case Study: Zarand Power Plant)

The increasing population and rising demand for water and energy supply, along with the exacerbation of environmental pollution effects on natural and human resources, demonstrate the vital need for a cohesive movement toward the water, energy, and environment Nexus (WEEN). Since the electricity generation industry has a significant share in water and fuel consumption and CO2 emissions in Iran, in this study, the application of a combined renewable system in the Zarand Steam Power Plant was evaluated based on the Nexus approach. Solar system designing and carbon balance evaluation during plant lifetime was conducted via PVSyst software in 2021. Also, an environmental model of ReCipe was applied to evaluate the effect of carbon reduction on the ecosystem. The results have shown that replacement of at least 1% of the nominal capacity of the fossil power plant with renewable sources, will significantly prevent 1249/46 t CO2 emission annually in this power plant which is equivalent to 362/160 m3 fossil resources storage and 373/73 TOE.year-1 energy savings. Also, the results showed that in addition to protecting valuable natural resources, the combined cycle will lead to a significant reduction in water demand equivalent to 3660 m3 having the capacity of supplying underground water resources. Considering the benefits of saving water and energy resources and reducing carbon emissions, from the NEXUS approach, in addition to managing energy supply through replacing resources and using water and heat recovery technologies, applying energy demand management policies based on energy efficiency and its environmental effects is suggested..