Abstract
With the urgent need to harvest and store solar energy, especially with the dramatic unexpected changes in oil prices, the design of new generation of solar energy storage systems has grown in importance. Besides diminishing the role of the oil, these systems provide green energy which would help reducing air pollution. Solar energy would be stored in different forms of energy; thermal, electric, hybrid thermal/electric, thermochemical, photochemical, and photocapacitors. The nature of solar energy, radiant thermal energy, magnifies the role and usage of thermal energy storage (TES) techniques. In this chapter, different techniques/technologies for solar thermal energy storage are introduced for both terrestrial and space applications. Enhancing the performance of these techniques using nanotechnology is introduced as well as using of advanced materials and structures. The chapter also introduces the main features of the other techniques for solar energy storage along with recent conducted research work. Economic and environment feasibility studies are also introduced.
TopSolar Thermal Energy Storage
In many parts of the world, direct solar radiation is considered to be one of the most potential source of energy. However, the large-scale utilization of this form of energy is possible only if the effective technology for its storage can be developed with acceptable capital and running costs (Kenisarin & Mahkamov, 2007). Thermal energy storage (TES), is of great importance in a wide variety of energy applications especially in solar energy storage applications. Thermal energy can be stored as a change in internal energy of a material as sensible heat, latent heat and thermo-chemical or combination of these techniques (Olofsson and Bengtsson, 2008). In his comprehensive study, Dincer (1999) introduced a discussion of the evaluation and the selection of sensible and latent heat storage technologies, systems and applications in the field of solar energy. Several issues relating to energy storage were examined from the current perspective. In addition, some criteria, techniques, recommendations, checklists on the selection, implementation and operation of energy storage systems were provided for the use of energy engineers, scientists and policy makers.
Key Terms in this Chapter
Latent Heat: The quantity of heat absorbed or released by a substance undergoing phase change.
Thermal Conductivity: A measure of the ability of a material to conduct heat
Nanocomposite: A multiphase material where one of the phases has one, two or three dimensions of less than 100 nanometers, (nm).
Nanotechnology: The science of manipulating atoms and molecules to fabricate materials, devices and systems.
Graphite Foam: A macro-porous graphite with foam like structure.
Solar: Radiant energy from the sun.
Thermal Energy Storage: Encompasses technologies that store thermal energy in energy storage reservoirs to be used afterward.
Phase Change Materials: Materials that have the ability to store or conduct a large amount of heat during their phase change.