The Corresponding Uncertainties and Slope Angles for a Solar Collector

Determination of the optimum slope angle of a solar collector is highly dependent on the incident solar radiations on the collector surface. As collected instantaneous data of incident solar radiation values are averaged, more attention must be directed towards these figures by determining the uncertainties in these measurements as this allows the calculation of the optimum slope angle. These average solar radiations give a definite optimum slope angle if they come along with the lowest uncertainties. Hence, this study aimed to find the optimum slope angles of solar collectors with corresponding uncertainties. For doing this, the solar radiation data borrowed from the Iranian Metrological Organization (IMO) which were measured on a horizontal surface in a period of twenty years (1986-2005), were employed. The results showed that the uncertainties of the optimum slope angles in some cities were quite high and it indicated that in this case more attention should be paid to select the appropriate optimum slope angle. These changes were more in cold regions compared to hot and dry regions because, the weather in the colder climates is typically more transient than the weather in hot and dry climates.

کلیدواژه ها:

slope angle ، Solar collectors ، Solar radiation ، Latitude