Study of the KNO3–LiNO3 and KNO3–NaNO3–LiNO3 eutectics as phase change materials for thermal storage in a low-temperature solar power plant

• Published in: Solar energy 2013-09, Vol.95, p.155-169
• Main Authors: Roget, F., Favotto, C., Rogez, J.
• Format: Article
• Language: English
• Subjects: Applied sciences; Chemical Sciences; Electric power plants; Electrical engineering. Electrical power engineering; Electrical power engineering; Energy; Energy. Thermal use of fuels; Engineering Sciences; Eutectic; Exact sciences and technology; Material chemistry; Materials; Molten salts; Natural energy; Nitrates; Non classical power plants; PCM; Photovoltaic power plants; Solar energy; Solar thermal conversion; Solar thermal power plants; Transport and storage of energy
• ISSN: 0038-092X; 1471-1257
• DOI: 10.1016/j.solener.2013.06.008

[Display omitted] •The eutectic compositions were determined using DSC.•The densities of liquid salts were measured by Archimedes method.•We report a latent heat storage capacity of 89kWhm−3 for binary eutectic.•We report a latent heat storage capacity of 86kWhm−3 for ternary eutectic.•The kinetics of crystallization were studied in a new large-scale calorimeter. For heat storage applications, the solid–liquid phase changes of the LiNO3–KNO3 and LiNO3–KNO3–NaNO3 mixtures of eutectic compositions have been investigated by Differential Scanning Calorimetry (DSC) and with a home built calorimeter working on large samples – typically 500g. The design of the new calorimeter matches at best the geometry and the thermal transfers in the industrial application. The kinetics of crystallization has been particularly studied. Density measurements of the salts in the liquid state allowed to calculate the volumetric storage capacity.