Performance improvement of solar-assisted air-conditioning systems by using an innovative configuration of a desiccant dehumidifier and thermal recovery unit

Abstract

The present study aims to construct an innovative configuration of a desiccant air conditioner that achieves thermal comfort conditions with the lowest electrical power consumption rates. To achieve this, an innovative configuration of a desiccant dehumidifier channel with multi-stages of silica-gel pads and heat exchangers for inter-cooling (DDC-MSSGP&HEI) was incorporated with the suggested air conditioner. The DDC-MSSGP&HEI is characterized by increasing the dehumidification capacity as well as cooling the process air with cooling rates higher than the heat generated by the adsorption heat effect. The thermal recovery unit was also incorporated with the suggested air conditioner to achieve the lowest electrical power consumption rates; it was utilized as a preheating unit to heat the regeneration air before entering into the solar collectors. The results showed that the system could supply air with a temperature of 12.2 °C and a humidity ratio of 7 gw kg da −1 , this is because of the positive effect of DDC-MSSGP&HEI. Also, the energy performance of the innovative configuration of a desiccant air conditioner is more efficient where TCOP and ECOP reached 1.96 and 3.14, respectively at a regeneration temperature of 90 °C. Moreover, the energy saving due to the utilization of the thermal recovery unit reached 28.7%. The economic feasibility indicates that the proposed configuration has the potential to save the life cycle cost by a rate of up to 33% compared to the conventional system with a payback period of 5.8 years.