Reflective mirrors effect on the performance of the hybrid PV/thermal water collector

Hybrid PV/Thermal collector is the collector which produced electricity and hot water or hot air at the same time and working as solar cells and solar heaters. This system has been designed to increase the electrical efficiency of the solar cells by withdrawing heat from the solar cells. The present study has been carried out in Kirkuk city (latitude 35.46 and longitude 4439), water was used as a mean to gain heat from the solar cell by passing it in a thermal exchanger, placed at the lower part of the solar cell, two proto types built to compare the thermal and electrical performance of the hybrid solar collector, the study includes making experiments for the months of (February, March, and April 2017, with a different volume flow rates, three variable designed had been studied, which includes the effect of the reflectance mirrors, glass cover and the slope angle of the lower reflector on the performance of hybrid PV/thermal water collector. The existence of the reflectance mirrors lead to increase the temperature of the solar cell therefore, its value was (92.7 degrees C) when using lower and upper mirrors with a glass cover, and (76.1 degrees C) when using only a lower mirror, and (71.35 degrees C) without reflecting mirrors. The cell surface decreased to (5275 degrees C) of the uncooled solar cell. The existence of the reflectors increases the total values of the thermal and electrical efficiencies. The daily total efficiency in average was a result due to use two reflectors was (81.03%), this means a positive effect on the total efficiency, and the effects of the glass cover on the total efficiency is big, the daily average of the total efficiency with and without glass cover was (58.95%) and (49.97%) respectively, these results are accorded with the results of the previous articles. (C) 2018 International Energy Initiative. Published by Elsevier Inc. All rights reserved.