Design and simulation of solar absorption cooling systems

The absorption chiller modeling is then exploited in a computer tool that gives valuable information on the planning of solar cooling systems. The design of these systems involves the choice of the main components, their sizing and an adequate control strategy of the whole. Several installations are present worldwide, but there is a lack of standard planning methodology. In the present thesis the focus is on the choice of the plant elements and their sizing. Energy savings and economic competitiveness are regarded as essential in guiding the design process. To find out an ideal sizing of the system the optimization-simulation approach is introduced. Once a typical system layout is chosen the TRNSYS environment is employed to see how different sizes of the system components effect the overall energy performance. The main design variables considered are the orientation of the solar collector array, the collectors area, the nominal capacity of the absorption chiller, the nominal capacity of the back up compression chiller, the volume of the thermal storages. Several simulations are launched by an external optimization programme, that retrieves the value of an objective function and changes the variables consequently. The procedure has been applied to a real planning case, carried out in two different installation sites. The results show that the economic convenience of solar cooling systems is really not easy going in the present scenario. Primary energy savings and reduction of electrical peak loads during hot season.