Potential evaluation and sizing of an off-grid photovoltaic generator for the energy supply of an irrigation system.

The use of photovoltaic (PV) systems is a useful solution for providing the required pumping power for irrigation of farms and gardens away from the grid (detached from the grid). The design of photovoltaic systems for water pumping completely depends on estimating the plant's water requirement. Because the water needs vary with time during the different irrigation season and solar radiation, performing accurate simulations is essential in order to achieve a successful and desirable design. The purpose of this paper is to provide a method for designing photovoltaic water pumping systems by combination water estimation relations and solar power models. In this study, Karaj station meteorological data during the ten year period (2005-2014) was used to estimate water demand and solar power. The water requirement of different months was estimated using the Penman-Monteith evapotranspiration model. The results showed that the highest water requirement was in July with 70 m3/day. It was estimated that in order to provide the necessary energy for daily pumping of up to 70 m3/day with a height of 30 m and taking into account the pump hydraulic efficiency and the efficiency of other components of the system, the pump with a power of 2200 W, the solar panel capacity of about 3222 W with 22 square meters area would be enough.