In recent years with the exacerbation of energy shortage around the world and the continuous increase in the level of greenhouse gas emissions, the use of various sources of renewable energy is increasingly becoming important for sustainable development.
Solar energy is considered to be one of the most promising sources of energy, owing to its clean and renewable characteristics. Thermal energy storage (TES) is used to assist in the effective utilization of thermal energy in wide number of industrial and domestic applications. Thermal energy is stored as sensible heat (SHS) or latent heat (LHS). Sensible heat storage (SHS) materials are combination of materials (both solids and liquids) which undergo no phase change in the defined temperature range of the storage process. Example concrete, cast steel, cast iron etc.
The use of a latent heat storage system (LHS) using phase change materials (PCMs) is an effective way of storing thermal energy and has the advantages of high energy storage density, narrow operating temperature range and the isothermal nature of the storage process. The phase change materials are more energy dense than sensible energy storage when the temperature difference between heat source and sink are low. Phase change material can store or release energy through its morphology change mechanism. These advantages lead to small volume and less heat loss, which attract attention of researchers in different fields. Ex: Sodium acetate trihydrate, NaNO3.
There are large numbers of PCMs that melt and solidify at a wide range of temperatures, making them attractive in a number of applications. PCMs have been widely used in latent heat thermal storage systems for heat pumps, solar engineering and spacecraft thermal control applications. The uses of PCMs for heating and cooling applications for buildings have been investigated within the past decade.
The experimental results computed in the field of water distillation process using solar energy in the presence of energy storage materials are discussed in this paper.