Energy storage in thermal systems plays an essential role in improving the reliability and efficiency of energy utilization. Among the different thermal energy storage technologies, sensible heat storage and latent heat storage are the most commonly used methods. These two systems store thermal energy in different ways and involve different materials, designs, and operating principles. A schematic comparison helps in understanding how these systems function and how energy is stored and released. Sensible heat storage systems store thermal energy by increasing the temperature of a material without changing its phase. In this method, heat is added to a storage medium, causing its temperature to rise. The amount of stored energy depends on the mass of the material, its specific heat capacity, and the temperature difference during heating and cooling. When heat is needed, the stored thermal energy is released as the material cools down. Common materials used for sensible heat storage include water, rocks, sand, concrete, and molten salts. Water is widely used because it has a high specific heat capacity and is inexpensive. Molten salts are frequently used in solar thermal power plants because they can store large amounts of heat at high temperatures. A simplified schematic of a sensible heat storage system can be illustrated as follows: Heat Source (Solar collector / Boiler) ↓ Heat Exchanger ↓ Storage Tank with Sensible Material (Water / Molten Salt / Rocks) ↓ Heat Delivery System (Steam Generator / Heating System) In this system, heat from a source such as a solar collector or industrial process is transferred through a heat exchanger into the storage medium. The temperature of the storage material increases, storing thermal energy. When energy is required, the stored heat is transferred back through another heat exchanger to a working fluid, which may generate steam or provide heating for buildings or industrial processes. Latent heat storage systems operate on a different principle. Instead of storing heat by raising temperature alone, they store energy during the phase change of a material, usually from solid to liquid or liquid to gas. The material used in latent heat storage is called a phase change material (PCM). During the phase transition, the material absorbs or releases a large amount of heat while maintaining nearly constant temperature. This characteristic allows latent heat storage systems to store more energy per unit mass compared to sensible heat storage. Typical phase change materials include paraffin wax, fatty acids, salt hydrates, and eutectic mixtures. Paraffin wax is widely