• Energy Research

Solar Photovoltaic Water Pumping (SPVWP) systems have established their potential as the most dependable and economically viable systems compared to the diesel based or grid-based electrical pumps. This paper presents an in-depth investigation of the energy efficiency of SPVWP system based on solar radiation, temperature, and operational heads. The study also identifies the shortcomings in the conventional design method based on Best Efficiency Point (BEP) concept that is applicable only in case of fixed frequency and voltage type pumps. However, in the case of SPVWP systems, due to variations in the solar intensity, ambient temperature, and water head, BEP concept does not offer the best efficiency design. The study experimentally proves that the model based on weighted system efficiency and Solar Operational Duty Head (SODH) increases the performance of SPVWP system (∼9% gain) and is consistently provide higher efficiencies in any season or under any climatic conditions.

Abstract The escalated targets for Solar Photovoltaic water pumping system (SPVWPS) installations in many Asian countries resulted in a huge demand for testing and certification of SPV pump samples. Test laboratories involved in testing and certifications are developing a generalized radiation and temperature profiles to cover various climatic conditions such as hot and dry, hot and humid, composite, cold and cloudy. The present paper addresses the challenges in the testing of a SPVWPS, through a step by step approach and devises solar radiation and temperature profile. Three types of testing profiles are designed to simulate “worst to worst”, “best to best” and “composite” conditions, so that evaluation of the sample can cover all the possibilities of pumping operation for the entire year. One of these three proposed testing profiles, the composite profile, reduces the total time of execution for testing of a sample, without comprising of any attributes of the testing method. Further, the developed composite radiation profile covers the large geographical area of the India and also other Asian countries and yet impart all realistic environmental conditions. The developed method of testing takes into consideration of the effects of individual components such as PV array, solar pump controller and motor pump set individually and collectively. The method also brings out superiorities and shortcomings in these components under the actual field conditions. All relevant experiment results are produced to verify the proposed testing methods.