Sorption technology is utilized in thermal cooling techniques. This technology can be classified as either open sorption systems or closed sorption systems 
. Desiccant cycles represent the open systems. Absorption and adsorption technologies represent closed systems.
Sorption refrigeration uses physical or chemical attraction between a pair of substances to produce the refrigeration effect. A sorption system has the unique capability of transforming thermal energy directly into cooling power. Between a pair of substances, the substance with the lower boiling temperature is called the refrigerant (sorbate) and the other is called the sorbent.