Experimental study of self-cleaning property of titanium dioxide and nanospray coatings in solar applications

Nowadays, the urgent need to replace fossil fuels with renewable energy is no secret. Therefore, researching in this area and developing the infrastructures necessary for the optimized utilization of these types of energy, are rising sharply. Among different kinds of renewable energy, due to easy access, solar energy has received special attention and extensive studies have been done, in order to increase the efficiency of the solar collectors and PV panels. One of the prime problems of solar systems in arid regions is the accumulation of dust on transparent surfaces, followed by an intensive drop in the transmission coefficient. In the present study, in a 70-day test period, up to 22% transmission coefficient loss, caused by the accumulation of dust on the surface, was observed. Thus, in order to solve this problem, Nanocoatings were deposited on glass samples to create self-cleaning property. A nanospray was used to create a hydrophobic film on the surface and TiO2 was coated in three different thickness to create a hydrophilic film on sample surfaces. Test results showed that these surface modifications have a significant impact in the reduction of dust accumulation and the loss of the transmission coefficient. Although there was no rain during the test, for samples with surface modification, the transmission coefficient drops were noticeably reduced. After rain simulation, the results indicate that transmission loss reduced from 22% to 0.5% and dust settlement problem was almost completely solved.