PV-Powered Microirrigation Systems

摘要

Tens of millions of farmers currently subsist on small farms below two hectares in size. The increasing cost of animal irrigation coupled with decreasing farm size and the lack of a utility grid or acceptable alternate power sources is causing interest in the use of solar photovoltaic for these very small (subkilowatt) water pumping systems. The attractive combinations of system components (array, pump, motor, storage, and controls) have been identified and their interactions characterized in order to optimize overall system efficiency. Computer simulations as well as component tests were made of systems utilizing flat plate and low concentration arrays, direct-coupled and electronic impedance matching controls, fixed and incremental (once or twice a day) tracking, dc and ac motors, and positive displacement, centrifugal and verticle turbine pumps. The results of these analyses and tests are presented for Orissa, India and Cairo, Egypt, and include water volume pumped as a function of time of day and year. Finally, a description and operational data is given for the prototype unit that was developed as a result of the previous analyses and tests. (ERA citation 04:054323)