Maximum solar energy produced by the proper orientation of collectors

In spite of common belief, it is not a collector oriented South that produces the most solar energy, since the Sun does not radiate as one would think with maximum intensity at noon. From the point of view of astronomy the Sun does not stay at the highest point on sky at 12 o'clock. It is evident that noon is at different times in the case of each and every town. However there is no great deviation in the Sun's position on the sky and the actual time on the clock within the borders of a country, which would noticeably modify the intensity of radiation. The atmosphere surrounding the Earth has a significant filtering effect thus reducing the intensity of solar radiation. The intensity of solar rays reaching the Earth's surface fully depends upon the atmospheric conditions. First of all it depends from the amount of atmospheric vapour, which absorbs and bends solar rays to a great extent. The rather complicated distribution of the intensity of average solar energy measured on a vertical surface throughout many years is well presented on the figure below.

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DISTRIBUTION OF SOLAR ENERGY ACCORDING TO ORIENTATION MEASURED ON A VERTICAL SURFACE IN THE SOPRON CLIMATIC REGION, IN MAY

The optimum orientation and inclination of collectors, which consequently produce the highest amount of energy, much depends upon the local climate. This optimum can only be determined on the basis of the averages of many years of meteorological data. This service is offered by the SunArch program, which enables the correct orientation and inclination of the given collector in order to produce the maximum solar energy. The program is based on averages of meteorological data, which has been collected through out many years. In the course of adjusting a collector once the orientation has been fixed one can either determine the most favourable inclination or the other way round, if the inclination is given, thane the orientation can be selected thus resulting maximum solar energy. In addition to this the duration of the period can also be set according to the calendar. In the case of a totally free horizon one can select the angle of orientation and the angle of inclination belonging to it, in order to produce maximum solar energy.

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Last modification: 28. May 2008.