Apirak SawatkitVarunyou Bunyaopas2562-06-122019-06-122558-08978-986-89844-3-1https://dspace.spu.ac.th/handle/123456789/6273This study aims to investigate efficiency enhancement of solar cells by using the mirror reflector to increase the intensity of sunlight. In conducting the study, 2 sets of 40-watt solar cells with the dimension of 470 mm. width x 676 mm. length x 2 mm. thickness, and a mirror reflector which was 235 mm. wide and 676 mm. long were used. The reflector was tilted at 67 degrees horizontal to one solar cell and the cell was faced southward at 14 degrees horizontal, the perfect angle for maximum sun exposure in the area of Pachee district, PhraNakhon Si Ayutthaya province, where the study was carried out. During the experiment, temperature, electricity current, voltage, and sunlight intensity were observed and recorded. The data was collected between April 9-15, 2014, from 6 a.m. to 6 p.m., the period when sunlight intensity reached the maximum point. Generally, the sky was clear and the temperature was high during that period, so it was expected that the efficiency of solar cells would drop. However, the study found that the solar cell with more focused sunlight due to the mirror reflector produced the power at the rate of 17.02% on the day when the temperature of the solar cell was 67.4 degrees Celsius. The data suggested the likeliness of higher efficiency and the average rate of 27.13% increase in energy output of the solar cell, compared to the typical efficiency of solar cells when no mirror reflectors were used.ensolar cells, reflectors, sunlight intensityArticle