A novel solar cooling cycle - A ground coupled PV/T desiccant cooling (GPVTDC) system with low heat source temperatures

This study investigates the performance of a novel desiccant air dehumidification and cooling cycle that utilises ground source heat exchange and flat plate photovoltaic thermal (PV/T) collectors (the GPVTDC system) to provide conditioned air. The system was modelled in TRNSYS using verified components with a focus on three climates: (i) an oceanic climate (Cfb) (ii) a humid sub-tropical climate (Cfa), and (iii) a hot semi-arid climate (BSh). The GPVTDC system pre-cools the entry air by utilising a ground source heat exchange. This allows the desiccant regeneration process to operate at low temperatures ranging from 43 degrees C to 62 degrees C, which enables the use of glazed water type PV/T collectors as the main heat source. The collectors were sized to match both thermal and electrical energy requirements to drive the GPVTDC system. The system was simulated for a whole year in each climate to provide fresh air ventilation, dehumidification and cooling process for an office space. Evaluation of the annual cooling performance of the GPVTDC system shows that it can maintain an office space within the thermal comfort zone for up to 93% of the time, with an average system cooling coefficient of performance (COP) between 9.6 and 16.3 for the three analysed climates. In addition, electrical energy saving up to 87% is achieved in comparison to a conventional dew point air dehumidification and cooling process. (C) 2020 Elsevier Ltd. All rights reserved.