Thermal energy storage (TES) is a technology that involves storing thermal energy for later use. It allows for the collection and retention of heat energy, which can be released when needed to provide heating, cooling, or power generation. TES systems are designed to bridge the gap between energy supply and demand, enabling better utilization of energy resources and increasing overall system efficiency.
There are several methods used for thermal energy storage:
Sensible Heat Storage: In this method, thermal energy is stored by changing the temperature of a material. Common materials used include water, rocks, bricks, or molten salts. Heat is absorbed or released as the material's temperature changes.
Latent Heat Storage: This technique involves storing thermal energy by utilizing the latent heat of phase change materials (PCMs). PCMs absorb or release heat energy during the process of changing between solid and liquid phases. Examples of PCMs include paraffin wax, salt hydrates, and some organic compounds.
Thermochemical Storage: Thermochemical storage involves storing energy by using reversible chemical reactions. Energy is absorbed or released during the chemical reaction. Thermochemical systems often use pairs of chemicals that can react with each other to store and release energy.
TES systems have various applications. They can be used in buildings to store excess heat during the day and release it during colder periods, thus reducing the reliance on heating systems. TES is also employed in solar thermal power plants, where it allows for continuous power generation even when sunlight is unavailable. Furthermore, TES can enhance the efficiency of industrial processes, such as in the storage and utilization of waste heat.
By efficiently storing and utilizing thermal energy, TES helps to optimize energy usage, reduce energy waste, and improve the overall sustainability of energy systems.