Calculation of the Optimum Tilt of a Stably Located Flat-plate Solar Collector.

The mathematical model and calculation method are given pertaining to solar radiation energy from an arbitrarily oriented and inclined plane, considering the influence of actual climatic and meteorological conditions in the geographical locality. These conditions represented mainly by the cloudiness are taken into consideration by the presented method using the quality of the mean relative monthly sunshine. The article compares the results derived by the method and by the computer program SOLEN with the corresponding values determined by actinometric measurements. The results of the program SOLEN based on the proposed method are in agreement with data determined from the measuremets. The article contains also a practical example of the use of the proposed method and program SOLEN in the area of direct use of solar energy for the determination of the optimum tilt of a stably located flat-plate solar collector.