The grid-connected system (PV ON Grid) in which solar modules are installed on the roofs of houses, factories, or schools in order to generate electricity and feed the public network of the state. It is preferable to design a system so that the energy produced daily from solar modules is within the range of 60% – 80% of The daily  energy  consumption of the establishment (KW.h), and thus the consumer saves the payment of electricity bills, and one of the most important features of this system is that it does not contain storage batteries for energy, which has a large economic return, whether as a construction cost for the solar plant or an operating cost as a result of replacing the batteries every number of years And according to the declared prices for electric energy in Egypt, the period of capital recovery for this system ranges from 5 to 10 years, according to consumption segments. We would like to emphasize that, according to the nature of our country, Egypt, the most economical system in solar energy applications is solar water Pumping systems compared to With diesel, as the period of capital recovery does not exceed three years, in addition to the problems of transporting fuel to farms in the desert, as well as reducing pollution resulting from diesel generators.