Design development and testing of a solar PV pump based drip system for orchards

A Solar Photovoltaic (PV) pump operated drip irrigation system has been designed and developed for growing orchards in arid region considering different design parameters like pumps size, water requirements, the diurnal variation in the pressure of the pump due to change in irradiance and pressure compensation in the drippers. The system comprising a PV pump with 900 W_p PV array and 800 W dc motor-pump mono-block, micro filter, main and sub-mains and three open-able low-pressure compensating drippers on each plant was field tested. The emission uniformity was observed to be 92–94% with discharge of 3.8 l/h in the pressure range of 70–100 kPa provided by the pump and thus the system could irrigate some 1 ha area within 2 h. Based on the performance of the PV pump and the drip system, it was inferred that about 5 ha area of orchard could be covered. The projected benefit–cost ratio for growing pomegranate orchards with such a system was evaluated to be above 2 even with the costly PV pump and therefore the system was considered to be an appropriate technology for the development of arid region.