Spectrum splitting through CuS–ZnO/water hybrid nanofluid for agricultural greenhouse cooling applications: An experimental study

Abstract In the present work, CuS–ZnO/water hybrid nanofluids (in concentrations of 0.0025 mass% and 0.005 mass%) are synthesized using a two-step method with nanoparticles composition 95% CuS 5% ZnO. The optically tuned nanofluid filter on agricultural greenhouse roof can reduce cooling load by transmitting visible spectrum absorbing near-infrared radiation in solar spectrum. size distribution nanoparticles, stability optical transmission both regions examined. Two hollow containers (i.e., ducts) thicknesses 4 mm 8 prepared. Each these ducts is attached to unit placed front simulator. experimental results reveal that applying CuS–ZnO reduces inside temperature under all irradiance ambient ranges. system gains an average 27.4% less heat from when flows through duct compared no-fluid case (empty duct). photothermal conversion efficiency found be higher than one for water. crop growth factor 82.2% obtained case, photosynthetic photon flux density reduced without affecting many plants. Furthermore, payback period (with duct) calculated as 0.42 years, application help system's energy requirement cooling.