Solar energy from renewable energy sources can be used for different purposes. The most common areas of use are electricity generation and preparation of hot water. While photovoltaic (PV) modules are used for direct electricity production, commercial vacuum glass tubes are used for hot water preparation. Electricity generation from solar energy is not limited to systems consisting of PV modules. When literature is viewed, it is seen that different methods are used for indirect electricity production from solar energy. One of them is concentrating solar power (CSP) system. In CSP systems, a fluid is used to transmit solar energy. Water vapor is obtained by the heat of the heated fluid with condensed the sunrays. High pressure water vapor is passed through a turbine, thus indirectly generating electricity from solar energy. This fluid used in CSP systems is called heat transfer fluid (HTF). HTF, consisting of a mixture of different materials, is an important factor in CSP's efficiency, performance and thermal energy storage. In this study, recent studies on HTFs used in CSP were investigated. The aim of this study is to help young academicians in our country by reviewing these studies.  

Keywords - Renewable Energy, Solar Energy, Concentrating Solar Power, Electricity Generation, Heat Transfer Fluid

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