Optimum tilt angle of a photovoltaic system: Case study of Algiers and Ghardaia

Solar energy systems are more accessible than earlier years. However, they are still more expensive than equivalent fossils powered. Therefore, to reduce costs, engineers should do an adequate design, and an important design parameter is tilt angle. The most recommended practice is to take it equal to the latitude. In this study, the effect of tilt angle on received and produced energy is examined in order to find its influence on systems efficiency. Two cities Algiers and Ghardaia were studied. The angle of inclination maximizing received and produced energy over the year is close to latitude. However, the angle maximizing the average minimum energy is close to latitude+23 in Algiers and in Ghardaia the optimum angle was close to latitude+10. In most cases, choosing Latitude+23 allows increasing the average minimum energy by up to 12%.