At the Master’s Thesis presented by Aleksandrs Zajacs „The solar energy use in air conditioning systems” the overview on the solar energy using technologies and peculiarities of design is given. There are determined selection path of appropriate technology depending on climate and building characteristics and defined optimal solar collector area and storage capacity for the system running with the simulating program assistance in the research section. There are described indoor thermal comfort parameters, advantages and disadvantages of different air conditioning system types and energy conservation principles within the framework of first two sections. There are described most commonly used solar cooling technologies and on the market available equipment of different capacity as well. There are defined optimal solar collector area and storage capacity for the system running in the office building with total area of 930 m2 using SACE: Solar cooling evaluation light tool.