EFFICIENCY IMPROVEMENT OF SOLAR MODULES UNDER LOW AND OBLIQUE LIGHT CONDITIONS

摘要

Within the framework of the research project ESOSWA (“Improvement of efficiency of solar modules under oblique and lowlight conditions”, funded by the BMBF, German Ministry of Education and Research), the Cologne University of AppliedSciences is conducting a detailed investigation on different textured module covers to increase the energy yield of solarsystemsunder unfavorable conditions.Using textured cover surfaces for PV-modules seems to be an appropriate answer to improve the performance of modulesunder oblique light conditions. As opposed to earlier studies [1], this paper investigates the influence of the optical behaviorof textured covers on the energy yield of PV systems as a function of module orientation and module l°Cation. Additionally,there is a need to develop a simulation-model for textured surfaces that can be implemented into currently used forecastingprograms.In a first step, the analyzed deep textured cover glass was compared to a standard solar glass. For this purpose, modules withand without deep surface texture were measured under different incident angles in the university’s testing facility. In a secondstep, the results of the measurements were used to simulate the enhancement of the energy yield for different Europeanl°Cations by using the textured glass cover. The simulations were realized with the software INSEL for all azimuth and tiltangles and took long-term diffuse and direct solar radiation data of Cologne, Germany, into account.The simulations of the energy yield of textured surfaces in comparison to standard solar glass show increases for all moduleorientations. For the l°Cation Cologne, Germany, with an orientation to the west or east and a tilt angle of 40°, the modulewith the textured surface showed a higher annual energy yield of 5.8 % compared to a standard solar glass module. Theenergy yield increases to 7.6 % for a north oriented module.