The energy consumption for space cooling is growing faster than for any other end use in buildings, more than tripling between 1990 and 2016. The efficient use of energy is important to reduce the consumption of electricity of conventional air conditioning. This chapter presents a thermal analysis of absorption and adsorption chillers for conditioning the airspace in a building, controlling the hot maximum temperature at the generator input with a modulating tempering valve (MTV) programmed in TRNSYS and Excel software. The energy performance of the system was maximized based on the tilt of the solar collector, storage tank specific volume, and input generator temperature. The results showed that 35 and 27 l/m2 of specific volume is a good ...