**3. Heat and mass transfer enhancements**

Enhancing the heat and mass transfer (HMT) of the adsorber is the most crucial part in developing ARSs. For a given cooling capacity, higher specific cooling capacity (SCC) means smaller amount of adsorbent to be used, and that can be a direct result of improving the heat and mass transfer performance of the adsorber. Besides, a lighter weight and smaller volume are existed in such case. As the adsorption system consumes less heat during regeneration modes, the COP is increased. Two methods are commonly used to increase the HMT: one is the development of adsorbents and the second is the optimization of the adsorber designs and cycle modes.
