Photovoltaic solar technology is undergoing remarkable progress and occupies an important place among the most used renewable energies. In the present study, the in uence of dust, wind and rain on the performance of a photovoltaic system operating in Arequipa -Peru was evaluated. To determine the e ciency of photovoltaic panels in uenced by external factors, a photovoltaic system was designed and installed, voltage, electric current, solar irradiance and temperatures were measured. For the dirt tests, three types of dust were used to simulate the atmospheric dust of the city: cement, ashlar (volcanic stone) and clay dust were used. The parameter considered for the deposition of the powders on the panels was surface density (g/m2). The particle size was determined by granulometry, the samples were analyzed by scanning electron microscopy and energy dispersive spectroscopy (SEM / EDS), obtaining spectra, microphotographs and chemical composition.For the wind factor, three speeds were determined within a range of average speeds recorded in urban areas, and tests were carried out in natural rain conditions. The results show that from 06:00 a.m. to 5:30 p.m. the energy generation e ciency of the photovoltaic panels decreases due to the increase of dust deposition. As well, it is shown that the in uence of the wind increases e ciency slightly and that the performance of photovoltaic panels is directly in uenced in rainy conditions.