The most mature and widely used approach is sensible heat storage. The selection of thermal energy storage depends on the type of energy source, required storage duration, operating condition, economic viability, etc. To obtain the above benefits for an energy system, it is critical to choose a suitable thermal energy storage approach. It has also been proven that the usage of TES can improve the performance of whole system operation, save the fuel consumption, lower the investment and operation costs, increase the energy supply security and mitigate the pollution to the environment if it is appropriately designed. TES has been applied in a broad range of fields: district heating, domestic hot water, thermal comfort, concentrated solar plants (CSP), chemical industry, food industry, etc. Among all the storage methods, thermal energy storage (TES) is one of the most economical systems in practical applications, and it allows the storage of thermal energy by heating or cooling a storage medium to be used at a later time. They are employed in different application fields depending on their specific characteristics on energy storage. In order to develop efficient and economical energy storage systems, various energy storage technologies have been proposed, such as compressed air energy storage, pumped storage hydro-power, flywheel energy storage, thermal energy storage, electrochemical energy storage, hydrogen storage and so on. With the energy storage systems associated to reduce the discrepancy between the demand and supply, solar energy systems can be more reliable and efficient in operation. This poses strong needs for energy storage in solar energy systems to store energy at high solar irradiances for later uses whenever there is a demand while solar irradiance is not enough. However, due to the intermittency in availability and constant variation of solar radiation, the output of a solar energy system is highly fluctuating if no or small inertia (thermal or electrical) is included. Solar energy is considered as one of the most promising renewable energy sources, because of its abundance and easy-access to the most parts of the world. , have been increasingly attractive to many countries for their natural advantages on sustainability and cleanliness. Renewable energy sources, including solar, wind, hydro, geothermal, etc.
The resulting global climate change and resource exhaustion can seriously threaten human survival and development. The long term usage of fossil fuels (e.g., coal, oil and natural gas) has caused environment pollutions and greenhouse effects. This chapter will be a useful resource for relevant researchers, engineers, policy-makers, technology users, and engineering students in the field.Ĭurrently, energy, environment and sustainable development are the major concerns to the countries all over the world. The emerging and future trends are finally outlined. Then, the most up-to-date developments and applications of various thermal energy storage options in solar energy systems are summarized, with an emphasis on the material selections, system integrations, operational characteristics, performance assessments and technological comparisons. In this chapter, various types of thermal energy storage technologies are summarized and compared, including the latest studies on the thermal energy storage materials and heat transfer enhancements. It is an effective way of decoupling the energy demand and generation, while plays an important role on smoothing their fluctuations. To eliminate its intermittence feature, thermal energy storage is vital for efficient and stable operation of solar energy utilization systems.
Solar energy increases its popularity in many fields, from buildings, food productions to power plants and other industries, due to the clean and renewable properties.