Effect of sorption bed modifications on adsorption chiller performance

The growing demand for sustainable cooling technologies promotes the development of systems capable of utilizing low-temperature heat sources. Among them, adsorption chillers represent an environmentally friendly alternative to conventional vapor-compression systems, as they can be driven by waste heat or solar energy. However, their wider implementation is still limited by their operational characteristics, including the relatively large mass and size of adsorption chillers, which result, among other factors, from insufficient heat transfer intensity within the sorption bed and at the sorption bed–heat exchanger interface. This study presents an experimental evaluation of a laboratory-scale adsorption chiller equipped with coated heat exchangers. The aim of the research was to analyze the effect of sorption bed modification on the operating parameters of the adsorption cooling system, with particular emphasis on the coefficient of performance (COP) and specific cooling power (SCP). The tests were conducted for different desorption temperatures and different adsorption/desorption cycle times, which enabled the influence of process conditions on the operation of the device to be assessed. The experiments were carried out using full-scale loose and coated sorption beds. In total, approximately 1200 adsorption and desorption cycles were performed, allowing the repeatability and stability of the system operation under cyclic conditions to be evaluated. The obtained results indicate that appropriate modification of the sorption bed and improvement of thermal contact within the adsorber can affect heat transfer dynamics and, consequently, the operating parameters of the adsorption chiller. The presented approach demonstrates the potential of sorption bed modification as a direction for developing more efficient adsorption cooling systems powered by low-temperature heat sources, representing an important step toward implementing circular economy principles in the refrigeration and air-conditioning sector.