الفهرس 
Chapter One: IntroductionOnly 14 pages are availabe for public view
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Abstract
People are always looking for new sources of energy to be able to meet their growing energy needs and keep pace with advanced life applications in the world we live in. Because most of the existing energy sources are at risk of depletion and expected to drain, in addition to their high cost and the negative environmental impacts resulting from using them extensively, we are now alerted to consider the potential of making use of other more sustainable sources of energy. For example, taking the solar energy and using it in various life aspects and activities. It is an easy, effective and safe source. This study aims at evaluating three types of solar water heaters and studying the effect of wind and dust that accumulate continuously on the glass surface of these solar heaters. We like to point out that the aim of printing this study is not only to compare these models with the well-known and conventional models, but we try also to make suggestions to select the simple and easy way of manufacturing them, considering the more poor villagers with their local skills and materials. For this purpose, three different types of solar heaters: Flat Plate, Serpentine and Corrugated heaters with different forms have been designed, considering maintaining similar dimensions and the same zones exposed for the sun rays, and tested them in the same climatic conditions in Minya Province – Upper Egypt. By this experiment, it has been observed that, Corrugated water heater is the highest in efficiency than the other two types .The experiment showed also that the dust layers accumulated on surfaces of the heaters reduce the solar heater absorption of heat and that the presence of high airflow contributes directly to heat loss, where water pipes become cooler inside, consequently, the efficiency of the solar water heater decreases by accumulating dust on the surface of the collector or increasing the wind speed targeted directly towards the collector.