Experimental and Simulated Analysis of Cloud Passage Effects on a Solar-Tracked Stand-Alone PV Water Pumping System
S. Artal-Sevil(1), J.M. Lujano-Rojas(1), R. Dufo-López(1), T. Vazquez-Pulido(2), J. Longás-Aranda(2), S. Bea-Alvarez(2) 1. Department of Electrical Engineering. Higher Technical School of Industrial Engineering, University of Zaragoza. Campus Río Ebro – Zaragoza 50018 (Spain). 2. Bombeatec. Research and Development Center). Avda. Anselmo Clave 37-45 Local. 50004 Zaragoza, Spain. 2025-07-25

Abstract

This paper presents an in-depth analysis and simulation of the effects produced by cloud passages on the operation of a stand-alone direct photovoltaic (PV) water pumping system. The study is based on a long-term experimental dataset collected at an isolated PV installation in Cariñena (Spain), specifically designed for agricultural irrigation. Cloud events were classified into three main types -cloud trains, compact clouds, and isolated cloud events- and their statistical occurrence and impact on system performance were evaluated across different seasons. A data-logger was developed to monitor key electrical and environmental parameters with high temporal resolution, enabling the identification and quantification of transient effects associated with sudden irradiance drops. The most critical situation arises during sequences of cloud trains, where frequent restarts and short operating cycles reduce the overall efficiency and increase mechanical stress. A simulation model was implemented to reproduce the dynamic behaviour of the system during cloud events, validating the experimental results and offering predictive capabilities for performance estimation. The novelty of the approach lies in the integration of cloud passage statistics with real-time performance analysis, allowing for a deeper understanding of the mismatch between energy generation and hydraulic demand. The study also highlights the advantages of direct PV pumping systems, such as simplicity, low maintenance, and cost-effectiveness, while highlighting their limitations under unstable weather conditions.

Key words: Cloud Passage, Photovoltaic Water Pumping System, Cloud Trains, Compact Cloud, partial shading, performance degradation.

References

[1] S.S. Chandel, M. Nagaraju Naik and R. Chandel. "Review of solar photovoltaic water pumping system technology for irrigation and community drinking water supplies". Renewable and Sustainable Energy Reviews, Elsevier ScienceDirect. Volume 49, September 2015, pp.: 1084-1099.

[2] J.S. Artal-Sevil, V. Ballestín-Bernad, J.M. Lujano-Rojas, R. Dufo-López, J.L. Bernal-Agustín. "Modeling of a stand-alone solar photovoltaic water pumping system for irrigation". Renewable Energy and Power Quality Journal (RE&PQJ), Open Access. July 2023, vol. 21; pp.: 662–667.

[3] Dufo-López, R.; Lujano-Rojas, J.M.; Artal-Sevil, J.S.; Bernal-Agustín, J.L. "Optimising Grid-Connected PV-Battery Systems for Energy Arbitrage and Frequency Containment Reserve". Batteries, MDPI Journals. 2024, vol. 10, issue: 12; pp.: 1–29.

[4]. M. Gasque, P. González-Altozano, F.J. Gimeno-Sales, S. Orts-Grau, I. Balbastre-Peralta, G. Martínez-Navarro and S. Segui-Chilet. "Energy Efficiency Optimization in Battery-Based Photovoltaic Pumping Schemes". IEEE Access, IEEExplore Digital Library. Vol. 10. May 2022; pp.: 54064–54078.

[5] R. Dufo-López, J.M. Lujano-Rojas, J.L. Bernal-Agustín, J.S. Artal-Sevil, A.A. Bayod-Rújula, J.A. Tejero-Gómez. "Short term energy management in stand-alone PV-battery-diesel systems". Renewable Energy, environment and Power Quality (REE&PQJ), Open Access. July 2024, Vol. 2; pp.: 233–239.

[6] V.C. Sontake and V.R. Kalamkar. "Solar photovoltaic water pumping system – A comprehensive review". Renewable and Sustainable Energy Reviews, Elsevier ScienceDirect. June 2016, vol. 50.; pp.: 1038–1067.

[7] J.S. Artal-Sevil, T. Vázquez-Pulido, S. Bea-Alvarez, R. Dufo-López. "Effect of cloud transits in a stand-alone solar photovoltaic water pumping system". Renewable Energy and Power Quality Journal (RE&PQJ), Open Access. July 2023, vol. 21; pp.: 677–682.