One of the popular solar air conditioning technologies is desiccant air conditioning. Nonetheless, single stage desiccant air conditioning systems’ coefficient of performance (COP) are relatively low. Therefore, multi-stage solid desiccant air conditioning systems are recommended. In this paper, an integrated double-stage desiccant air conditioning systems and PV/T collector is suggested for hot and humid climates such as the UAE. The results for the PV/T implementation in the double-stage desiccant cooling system are assessed against the PV/T results for a single-stage desiccant air conditioning system. In order to provide a valid comparative evaluation between the single and double stage desiccant air conditioning systems, an identical PV/T module, in terms of dimensions, is incorporated into these systems. The overall required auxiliary air heating is abated by 46.0% from 386.8 MWh to 209.0 MWh by replacing the single stage desiccant air conditioning system with the proposed double stage configuration during June to October. Moreover, the overall averaged solar share during the investigated months for the single and double stage systems are 36.5% and 43.3%.
In this paper, different approaches are considered to calculate the cosine factor which is utilized in Campo code to expand the heliostat field layout and maximize its annual thermal output. Furthermore, three heliostat fields containing different number of mirrors are taken into consideration. Cosine factor is determined by considering instantaneous and time-average approaches. For instantaneous method, different design days and design hours are selected. For the time average method, daily time average, monthly time average, seasonally time average, and yearly time averaged cosine factor determinations are considered. Results indicate that instantaneous methods are more appropriate for small scale heliostat field optimization. Consequently, it is proposed to consider the design period as the second design variable to ensure the best outcome. For medium and large scale heliostat fields, selecting an appropriate design period is more important. Therefore, it is more reliable to select one of the recommended time average methods to optimize the field layout. Optimum annual weighted efficiency for heliostat fields (small, medium, and large) containing 350, 1460, and 3450 mirrors are 66.14%, 60.87%, and 54.04%, respectively.
A study was conducted to investigate the performance of thin film flexible PV panels. The experimental study was conducted to simulate the performance of the panels for the conditions found during the unmanned aerial vehicle (UAV) flight in the city of Sharjah. Two 2 m and a single 1 m <i>WaveSol Light</i> PV panels were tested for the study. The 2 m panels are for each wing while the 1 m panel is for the horizontal stabilizer. <i>WaveSol Light</i> PV panels were considered for this research because of their relative light weight, high current and compatible voltage output. These PV panels also have a convenient width which can easily be mounted on the UAV wings and stabilizer. The panels were tested to measure the voltage and current over the test period of 19 minutes. A detailed parametric study was conducted to evaluate the flight duration and the performance of the UAV for regular operations. The study predicted the operational range and flight performance based on the motor power requirement, PV panel system type and fuel cell capacity. The best case scenario achieved the endurance increase of 4.5 hours while the worst case achieved an endurance of 0.4 hours.