Abstract
Concentrated solar power (CSP) is the conversion of the sun's energy into thermal energy by concentrating the solar radiation by means of mirrors or any other optical element such as lenses on a receiver containing a liquid such as water, molten salt, industrial oil or compressed gas to provide heat for heating and for industrial purposes or to generate steam that rotates a turbine to produce electricity. CSP plants may contain thermal storage units to provide electrical and thermal energy during the night or when the weather is cloudy. Concentrated thermal and electrical energy generation requires high direct solar radiation (DNI) which represents 90% of the sunlight on a sunny day and its value is neglected on a cloudy day, so (CSP) is effective in the sun belt regions, which are located at latitudes between 15 and 40 degrees north and south of the equator, these regions include: the Middle East, North Africa, South Africa, India, southwestern United States, Mexico, Chile, Peru, eastern China, Australia, southern Europe and Turkey. Also, solar radiation is high at high latitudes, as dispersion is low. The best areas to install CSP plants are the areas where direct solar radiation (DNI) is greater than (2800 kwh/m2 per year). The time taken to build CSP plants is from (1-3) years depending on the size of the plant, and its operational life is more than 30 years. The area needed by these plants is 2 hectares per megawatt. This article highlights on the systems for generating electric power from concentrated solar energy and presents the different fluids used in heat transfer, as well as the methods of thermal storage.