Dynamic simulation of desiccant cooling system with simultaneously using solar and ground renewable energies in hot-humid regions

In this paper, the dynamic operation of a desiccant cooling system combined with solar and ground source renewable energies has been presented. Solar energy has been used for providing the required energy for regenerating the desiccant wheel (DW), and the ground source heat exchanger (GSHE) has been exploited as an air pre-cooling component. Transient operation of the desiccant system has been performed using TRNSYS software. The potential of the system in providing thermal comfort has been assessed in hot-humid regions. Results reveal that the studied desiccant system is capable of providing thermal comfort in these regions with low-grade regeneration temperatures (lower than 75 ℃). As a new perspective, the maximum value of the DW regeneration temperature has been controlled. The effect of the DW performance and its maximum regeneration temperature has been evaluated on the behavior of the system. Regarding the results, high performance DW can increase the provided thermal comfort up to 40% and contribution of solar energy up to 14% compared with its low performance. With reduction in maximum value of regeneration temperature to 50 ℃, the achieved thermal comfort will be decreased to lower than 30%. Using the GSHE in the system enhances the thermal comfort and a specified level of that can be provided with lower regeneration temperatures. The conducted economical assessment show that in the situation in which the system entirely provides thermal comfort, the payback period is calculated to be 8.2 years.