Improving the efficiency of solar panels using gas-filled double glazing technology as a means of radiative cooling

Solar energy is an excellent source of renewable energy and has many advantages, such as being pollution-free, non-exhaustible, and freely available. The use of solar panels is an important way to convert solar energy into electricity, but high temperatures affect their performance, so they always need cooling to increase the conversion efficiency. A spectral selective filter can be used to manage sunlight by blocking some infrared wavelengths and allowing visible radiation to pass while increasing thermal emissions from the PV modules through the use of gas-filled double glazing technology, which effectively contributes to their cooling, which is a more feasible method. And attractive for cooling solar panels. The current work presents a passive radiative cooling technique to increase the efficiency of electrical conversion by reducing the operating temperature through a glass filter consisting of two layers of glass with a thickness of 4 mm and with different gaps ranging from 10 to 25 mm. The gaps are filled with carbon dioxide. The filter is placed above the plate. 50-watt solar panel, leaving a 30 mm gap between the gas filter and the solar panel. This filter absorbs or reflects infrared rays that cause excess heat and prevents them from reaching the surface of the solar panel for the purpose of cooling it and allowing the wavelengths useful for operating the photovoltaic panel to pass through it. The practical experiments were carried out under the local weather conditions of the city of Baghdad, Iraq (latitude 33.22 degrees north and longitude 23.44 degrees east). The photovoltaic panel was oriented towards the south at an angle of 33 degrees. Trial readings were taken for the months of July and August, and August 15 was approved for discussion. The results showed that the weather conditions were suitable in terms of dust and clear skies. The technologies used in cooling were tested on two photovoltaic panels, the first with carbon dioxide glass filtration technology, and the second panel was left as a reference to compare the improvement in thermal and electrical performance. The results showed that the ideal gap was 20mm, the greatest amount of PV panel surface temperature reduction was 5 to7.3 °C, the efficiency improved to 8.7%, and the output power improved by 11.2%.