Molten salt as phase change materials can be used as thermal storage medium in concentrating solar power (CSP) system. It is possible to significantly improve the thermal properties of molten salt by adding nanoparticles to molten salt. Nanofluids were synthesized by dispersing 20 nm SiO2 particles to potassium nitrate

sodium nitrate

and solar salt (60% NaNO3 and 40% KNO3

mass fraction) respectively. Nanofluids were prepared by water-solution

sonication

and evaporation. The thermo-physical properties (latent heat

specific heat and molting point) of nonofluids were characterized by DSC method

and the thermal diffusivity was analyzed by laser flash apparatus (LFA). Results show that mass fraction of 20 nm SiO2 particles significantly enhanced latent heat

specific heat and thermal conductivities of potassium nitrate

sodium nitrate

and solar salt. Compared with base salt

the average specific heat improved of solar salt

potassium nitrate

sodium nitrate with 20 nm SiO2 nanoparticles was found to be 4.7%-15.89%

3.9%-33.5%

1.9%-11.86% in liquid

and the maximum thermal conductivity increased by a maximum of 17.16%

39.7%

and 9.5%

respectively.