Today, electricity has become an essential part of the life. At present, a large part of the electricity is supplied by thermal power plants and hydropower plants. With increasing concerns about greenhouse gas emissions and other environmental issues new technologies such as using solar energy for electricity generation are recommended. In this paper, a typical 500-kilowatt solar power plant connected to the grid is evaluated. Simulations are implemented by PVsyst software and its performance on different climatic conditions is investigated. Moreover, the performance ratio and different types of energy losses (such as losses due to temperature increases, the domestic network losses, losses of power electronics (convertors)) are calculated. Finally, the amount of energy produced and injected into the network and the annual income from the construction to the south of Tehran, Kerman and Yazd are compared. Results show that the city of Yazd as a suitable site for the construction of the plant is the best alternative among other two options.

For decreasing the amount of air pollution and green gas emission and saving fossil fuels resource, one of the ways is extending renewable energy utilization. Hence, this yields to growth and development of Photovoltaic systems. Nowadays due to increasing electrical energy requirements and ability to privately providing required energy, the use of solar energy and its electrical power creativity by means of PV systems expanded. In this study an electricity network independent system designed to provide electricity for a house around Karaj at a certain season of the year. The energy demand for this house is 4320 Watt-hours. For providing this amount of energy, 830 watt photovoltaic array, a 1500-watt inverter, a charge controller with a capacity of 40 amp and 24 volt battery with 600 amp hour capacity is needed. The cost needed for this project estimated about 103700000 Rials. PVsyst software used to calculate system losses and finally environmental impact of system compared with conventional systems.