Techno-economic feasibility of off-grid solar irrigation for a rice paddy in Guilan province in Iran: A case study

- A lifecycle cost analysis for two types of pumping system is performed.
- Techno-economic feasibility of a solar powered pumping system is examined.
- The required pumping power and panel area for a paddy with specified area is calculated.
- Daily average and maximum global solar irradiance in the north of Iran is studied.
- Mean monthly clearness index during irrigation period is measured.

In this study, a typical rice paddy in Guilan province of Iran is considered and the technical and economical feasibility of the solar powered pumping system is studied. The monthly mean daily solar irradiance has been studied for this area and the measured data is compared with European Photovoltaic Geographic Information System (EU PVGIS) model for Middle East, including Iran. The investigations imply that the average monthly mean daily solar irradiance in irrigation months are reported equal to 5.92 kW h/m2/day by Guilan Meteorological Administration and 5.95 kW h/m2/day by EU PVGIS. A mean monthly clearness index from 0.54 to 0.57, in irrigation period, gives Guilan province a good potential to employ photovoltaic (PV) pumping system. In this study, the appropriate size of the PV panels and the lifecycle cost estimation of PV pumping system in comparison with conventional systems are presented. Also, the area of the PV solar panel to supply required power of the pumping system for a rice paddy with specified area is calculated. Results show that though the initial outlay of the PV system is about 9 times of the conventional systems but the total lifecycle costs of the PV pumping system is just 65.6% costs of the conventional pumping system. Also in spite of high initial costs of the PV pumping system, it is found that after around 9 years, the total costs of both systems would be equal to conventional one i.e. gasoline pumping system and after this time, the costs of the conventional pumping system will exceed the PV solar panel system.