نوع مقاله : مقاله پژوهشی
نویسندگان
دانشکده مهندسی شیمی، دانشگاه تربیت مدرس
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
There are three factors which affect the efficiency of the solar panels: the semi conductor material, solar radiation flux intensity, and solar panel operating temperature. Increasing the elevated operating temperature in solar photovoltaic cells induces a significant decrease in the efficiency. For photovoltaic panels, high operating temperatures cause a drop in the conversion rate of about 0.3\%-0.5\% per Celsius degree over the nominal cell operating temperature of $25^{0}C$.To keep the operating temperature lower, one can either improve the free cooling on the back of the panel, thanks to natural or forced convection, or try to absorb the excess heat by modifying the panels architecture. The latter solution includes the use of phase change material PCM situated on the back of the solar panels. This paper represents the results of an experimental investigation into using PCM for thermal management of photovoltaic devices to maintain the temperature of the panel close to the optimum temperature. Polyethylene glycol 1000 (PEG 1000) was used as a PCM. The materials were injected in the cubic ducts, and these ducts were fixed on the back of the solar panel. Experimental runs were done in radiation of $800 W/m^2$. Also, two angles of horizontal and 15 degree inclination were examined. Results show that the consumption of PCM improves the efficiency of solar panels in electricity production. Also, it can maintain the temperature of the panel $15^{0}C$ lower in comparison to a single panel without PCM. This causes an 8\% improvement in overall efficiency. Also, an increase in panel inclination has a positive effect on cooling. This is because the gushing of liquid PCM makes a forced convection in the PCM ducts. Using phase change materials seems to be an effective method for the efficiency enhancement of solar cells.
کلیدواژهها [English]