Abstract
High-temperature solar thermal systems are a key component of using solar energy for many industrial uses, such as process heat, desalination, and power production. However, the performance of these systems significantly relies on the properties of the heat transfer fluid (HTF) employed. Conventional HTFs, including molten salts and synthetic oils, have drawbacks that prevent them from being widely used, like low thermal stability, corrosion problems, and high viscosity at high temperatures. To overcome these challenges, scientists focus on developing novel HTFs with enhanced thermal stability, improved heat transfer properties, and reduced environmental impact. One of the promising strategies involves using nanofluids, which are colloidal suspensions of nanoparticles in a base fluid. Compared to traditional HTFs, nanofluids exhibit better thermal conductivity, making them attractive options for high-temperature solar applications. Liquid metals are another attractive avenue for the exploration of advanced HTFs. Efforts are being made in combinatorial material synthesis and high-throughput characterization techniques to identify optimal compositions of liquid metals. Moreover, research is being done to investigate alternative base fluids that provide better thermal stability and compatibility with solar collector materials, such as eutectic mixtures and organic compounds. Computational modeling and experimental studies are being conducted to comprehend the basic mechanisms governing heat transfer and fluid behavior in high-temperature solar systems using advanced HTFs. The development of advanced HTFs holds great potential for improving high-temperature solar thermal systemsÂ’ efficiency, reliability, and cost-effectiveness, facilitating the transition toward a sustainable energy future. Continued research and innovation in this area are crucial to unlocking the full potential of solar energy as a clean and ample renewable energy source for meeting global energy demands. Comprehensive information on the development of advanced HTFs for high-temperature solar thermal systems is presented in this chapter.
