ABSTRACT

 In the design of photovoltaic water pumping system, the exact estimate of the water flow is a prerequisite for optimized implementation and system strength. In this research work, an empirical mathematical model is developed and presented to characterize the photovoltaic water pumping subsystems used in pumping installations. Then evaluations were made expressively on the water flow output (Q) directly as a function of the electrical power input (P) to the motor pump, at varying total dynamic head. The investigations concerning centrifugal and positive displacement motor-pump subsystems were detailed to study their performance in the model structure and behavior in accordance with the locations of solar radiation. Analysis was validated by means of the experimental tests to cater for height variation. The results obtained from the experiment showed a high level of relation between the test results and the simulated values with minimal root mean square error. Based on the motor-pump subsystem model, a method is proposed to estimate the amount of carbon dioxide (CO2) emissions saved by the use of water pumping facilities powered by a photovoltaic array instead of diesel fuelled generators. By means of carbon emission coefficient for diesel, the results show mitigation of 24.14 tons of carbon dioxide annually while the cost for water pumping with a 10KW rated PV panel is 0.2528$/m3at 40m total dynamic head. The overall analysis shows that the adoption of PV water systems contributes to improved living conditions in rural communities, and is also environment friendly