A Comparative Investigation of Energy Storage Potential of Nanoparticles Doped in Black Paint Coated Absorber for Solar Desalination Application

This work explored the performance of solar still using different nanoparticle doped in black paint coating. Nanoparticles such as reduced graphene oxide (RGO), CuO and TiO₂ of size 30–50 nm were selected, then a solution comprised of turpentine/black paint (1:4) was taken and these nanoparticles were mixed and the solution was stirrer to achieved homogeneous solution of three different type. Four solar still, one with absorber coated using bare black paint and the other three solar still with different nano particle coated absorber were fabricated and tested in Jaipur, India. Maximum heat transfer coefficient was demonstrated by RGO coated SS, owing to the excellent solar absorption behavior along with higher thermal conductivity. Conventional SS with bare black paint coated absorber showed maximum hourly water yield of 0.7 L. The maximum hourly water yield of 0.88 L was shown by RGO coated absorber due to phenomenal thermo-physical properties, which promotes higher heat transfer rate and evaporation rate. However, CuO and TiO₂ showed maximum hourly water yield of 0.84 L, and 0.77 L, respectively.