Performance of solar refrigerating units using ammonia, methylamine, ethylamine, dimethylamine, methanol, and ethanol as refrigerants (adsorbates) and activated carbon as adsorbents has been studied. A mathematical model has been built to determine the level of thermodynamic perfection based on simplified theoretical operation cycle and gradual integration of experimental and calculated values of daily variation of the key parameters of the refrigerating unit. A solar power unit where horizontal insolating tubes and plane mirror concentrators are used has been built and successfully tested.One way of utilizing solar energy (radiation) for refrigeration is to use ecologically safe solar adsorption refrigerating units (SARU).Operation of such units is based on the physical adsorption process in which the molecules of a gaseous refrigerant cluster up over the solid surface of the sorbent, followed by condensation, upon cooling, of the vapor of the refrigerant in the porous structure of the sorbent. This process is reversible, i.e., when heat energy is supplied, the refrigerant (adsorbate) is desorbed from the adsorbent.The flow diagram of the SARU does not differ from that of "dry" solar sorption units [1]. The presence of the solid sorbent predetermines the periodicity (cyclicity) of operation of such a unit. During the day, due to solar heating in the generator, the refrigerant is released (desorbed) from the saturated adsorbent and is accumulated in a receiver upon liquefaction in a condenser. During the night, the refrigerant is adsorbed as the adsorber cools off, whereupon cooling effect is produced in the evaporator.In the SARU, ammonia (NH 3 ), methylamine (CH 3 NH 2 ), ethylamine (C 2 H 5 NH 2 ), dimethylamine (CH 3 ) 2 NH, methanol (CH 3 OH), and ethanol (C 2 H 5 OH) can be used as refrigerants-adsorbates and activated carbon, as adsorbents.In the process of producing activated carbon, hydroxyl (-OH) and carboxyl (-COOH) groups may form on its surface, so the carbon may be both nonpolar and polar and exhibit properties of cations, anions, or ampholytes.The adsorbates containing electronegative elements (oxygen, nitrogen, etc.) may form associates (micelle) owing to formation of hydrogen bonds and the amine and alcohol molecules may exhibit diphilic properties due to polar functional groups (-NH 2 and -OH) and nonpolar radical (-R); the molecules of the surface-active substances may form associates depending on the polarity of the surrounding phase. Having dipole moments, the adsorbates also may form associates on account of electrostatic interaction of the dipoles [2].Based on their basicity strength, the adorbates can be arranged in the following order: C 2 H 5 NH 2 > (CH 3 ) 2 NH > > CH 3 NH 2 > NH 3 > C 2 H 5 OH > CH 3 OH.The base is an electron donor (nucleophile) [3]. Presence of carboxyl groups (-COOH) on the carbon surface facilitates formation of stronger bonds with strong bases.