Abstract:

Day by day water resources in the world are getting shortened and agricultural lands are gradually getting dry. Water extraction for agricultural purposes in the regions far away from the electric network, brings extra costs. In the regions that are close to the electric network, high electric bills are encountered. In irrigation systems, cost-efficient and high performance power generation is possible thanks to the solar energy. When parameters such as the quantity of water and the well height required are known, cost-efficient agricultural irrigation can be achieved by proper pump selection. In this study; dynamic change realized on daily and annual basis was researched for off-grid photovoltaic pump system (PVPS) that is attached to photovoltaic (PV) panels. In this system, PV panels are directly attached to the pump that feeds a tank placed high above. According to the measurements performed in the application area, Malatya province; analyzes were carried out on solar radiation, change of temperature, electrical efficiency and pump water flow. Months that had similar solar radiation and temperature values, were gathered under three different groups. That is, instead of monthly data, months that were of similar nature, were named as the Warm period, Lukewarm period and Cold period. In consequence of the study, major changes were observed in the system flow and efficiency throughout the day. Therefore, it was determined that designing any PVPS application according to daily average values without investigating the dynamic process, would cause performance decrease and additional costs.

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