Designing an off-grid PV system: For a residential consumer in Mashhad-Iran

This article suggests an off-grid solar power system for a typical home at Mashhad, IRAN. In order to computing the off-grid solar system components. The design was done based on the shortest day of the year. The solar data is obtained from NASA web site and has been used from RETSCREEN software. The solar system set must capable to supply load current for 4 days; therefore we need to install Batteries and battery charger. In this computation the shortest day of the year has been assumed. Although the total design is acceptable from engineering point of view, from economical view the total Cost of system is higher than the case that has been designed for summer days that the electricity cost is higher in IRAN country.