## Modeling of Solar Energy Yield of a Fixed, Titled and Tracking Solar Collectors Under Clear sky Condition: A comparative Study

The production of electric energy based on solar radiation is one of the most important priorities in the world of clean energy, and the big-gest challenge has become to know which systems are the most produc-tive of energy. Through the current research, three models of PV systems classified according to their mechanism of work were dealt with, as follows: The first type is the horizontal solar collector, the second is the tilted solar collector, and the last is the dual-axis tracking solar collector. Using the Matlab program, and based on the clear sky conditions, it was expected the amount of solar radiation absorbed by each of the three systems, and the amount of electrical energy that can be produced in each of them during daylight hours throughout the summer season. After that, it became clear that the solar collector system that con-tains the dual-axis tracker is the highest productivity of electrical ener-gy, followed by the tilted system, and finally the horizontal one. Where-as, the quantity of electrical production of the three solar collector sys-tems appeared as follows, from highest throughput to lowest, respec-tively 2366.75kWh , 2476.30kWh, 3709.71kWh. On the other hand, which is the economic side, the solar tracker proved to be the most eco-nomical, as despite its high price in its construction, it was the lowest price per kilowatt hour among the three systems, where the horizontal, inclined and tracker systems recorded the following prices respectively 0.206$⁄kWh , 0.197$⁄kWh , and 0.183\$⁄kWh. While dual-axis solar tracking model is the only one among the mod-els that study them, which consumes energy during its work because it contains a motor for movement in order to track the sun , this quantity consumed was very little as compared to produced energy , almost neg-ligible. To find that this matter did not affect the survival of this model in the forefront in terms of productivity and economical.