Different bed configurations and time ratios: Performance analysis of low-grade heat driven adsorption system for cooling and electricity

In this study, different multi-bed water adsorption systems have been used to generate cooling and electricity at the same time using 9 different cases including 7 bed configurations and 7 time ratios (R = total switching and adsorption time /the total switching and desorption time) utilizing advanced adsorption materials such as AQSOA-Z02 and MOF Aluminium-Fumarate additionally to traditional Silica-gel. A MATLAB Simulink program of multi-bed adsorption system for cooling and power generation has been developed to investigate the effect of using different cases on the overall system performance. Results showed that using three-bed configuration with time ratio of (R = 1/2) produced the highest specific cooling power (SCP) and specific power (SP) for Silica-gel (for all heat source temperature range), Aluminium-Fumarate (for heat source temperature higher than 120 °C) and AQSOA-Z02 (at heat source temperature of 160 °C). Moreover, using two-bed configuration with time ratio of (R = 1) generates the highest coefficient of performance (COP) for all adsorption materials within the range of heat source temperature used in this study. Results also, showed that maximum COP of 0.64 can be achieved using Silica-gel, while maximum SCP, SP and adsorption power efficiency of 650 W/kgads, 64 W/kgads, 4.6% can be achieved using AQSOA-Z02.