OPERATING-MODE OPTIMIZATION OF DRAINAGE PUMPING STATIONS SUPPLIED BY FLOATING PHOTOVOLTAIC PLANTS: INTERNATIONAL EXPERIENCE AND PROPOSALS FOR THE REPUBLIC OF KARAKALPAKSTAN
Keywords:
drainage pumping station; floating photovoltaics; collector-drainage water; operating mode; self-consumption; Karakalpakstan.Abstract
Drainage pumping stations in Karakalpakstan consume large amounts of electricity, while the same region receives high solar radiation and collects large volumes of collector-drainage water that can be stored in artificial reservoirs. This paper analyses international experience with floating photovoltaic (FPV) plants, solar-powered pumping and pump scheduling, and derives proposals for Karakalpakstan. The analysis shows that (i) FPV is a mature technology, with plants of 45–150 MW already operating on reservoirs; (ii) a regulating reservoir acts as a hydraulic energy store that can shift pump load to solar hours; (iii) parallel pumps and limits on the number of starts improve both energy use and pump life; and (iv) no published work combines these elements for drainage stations. Six proposals are formulated: station screening, a reference configuration, a solar-following operating rule, saline-water durability requirements, a monitoring programme and a three-phase implementation roadmap. Quantitative targets are expressed as indicators to be verified on site data.
References
World Bank, ESMAP, SERIS. Where Sun Meets Water: Floating Solar Market Report. Washington, DC: World Bank, 2019.
Power Technology. The world's biggest floating solar farms. https://www.power-technology.com/features/worlds-biggest-floating-solar-farms/
RenewEconomy. Indonesia's solar plans go to water with opening of region's biggest floating PV facility. https://reneweconomy.com.au/
IEA. Solar Energy Policy in Uzbekistan: A Roadmap. Paris: IEA, 2022.
Wei Y., Khojasteh D., Windt C. An interdisciplinary literature review of floating solar power plants. Renew. Sustain. Energy Rev. 2025, 209, 115094.
Southeast Asia Construction. Sembcorp to build Singapore's largest floating solar farm. 12 Feb 2020.
Redón-Santafé M., Ferrer-Gisbert P., Sánchez-Romero F., Torregrosa Soler J.B., Ferrán Gozálvez J.J., Ferrer Gisbert C.M. Implementation of a photovoltaic floating cover for irrigation reservoirs. J. Clean. Prod. 2014, 66, 568–570. doi:10.1016/j.jclepro.2013.11.006.
Redón-Santafé M. et al. Self energy production by a floating photovoltaic system covers for irrigation reservoirs (Aspe irrigation community case study). Springer, doi:10.1007/978-3-319-12754-5_16.
Cazzaniga R., Cicu M., Rosa-Clot M., Rosa-Clot P., Tina G.M., Ventura C. Floating photovoltaic plants: Performance analysis and design solutions. Renew. Sustain. Energy Rev. 2018, 81, 1730–1741.
Numerical analysis of evaporation reduction in floating photovoltaic power plants: influence of design parameters. EPJ Photovoltaics 2025, 16, 4.
Eshra N.M., Salem M.G. Solar energy application in drainage pumping stations to save water and reducing CO₂ emission. Energy Reports 2020, 6, 354–366.
Optimal short-term water-energy dispatch for pumping stations with grid-connected photovoltaic self-generation. J. Clean. Prod. 2021, 316, 128386. doi:10.1016/j.jclepro.2021.128386.
Carricondo-Antón J.M., Jiménez-Bello M.A., Manzano Juárez J., Royuela Tomas A., González-Altozano P. Optimization of an isolated photovoltaic water pumping system with technical–economic criteria in a water users association. Irrig. Sci. 2023. doi:10.1007/s00271-023-00859-6.
Government portal of Uzbekistan. Projects to improve water supply considered. https://old.gov.uz/en/news/view/35978
Kodirov D.T., Ermanov R.A., Sherbaev M.R., Musurmonov M.A. Analysis of pump stations operation mode and measures to improve them. E3S Web Conf. 2023, 401, 02020. doi:10.1051/e3sconf/202340102020.
Matchanov A.T., Kurbaniyazov A.K. Present hydrological state of the collector waters in the lower reaches of Amu-Darya river. Geophys. Res. Abstr. 2005, 7, 06496.
Angadi S., Yaragatti U.R., Suresh Y., Raju A.B. Comprehensive review on solar, wind and hybrid wind-PV water pumping systems. CPSS Trans. Power Electron. Appl. 2021, 6(1), 1–19.
Poompavai T., Kowsalya M. Control and energy management strategies applied for solar photovoltaic and wind energy fed water pumping system: A review. Renew. Sustain. Energy Rev. 2019, 107, 108–122.
Gasque M., González-Altozano P., Gutiérrez-Colomer R.P., García-Marí E. Optimisation of the distribution of power from a photovoltaic generator between two pumps working in parallel. Sol. Energy 2020, 198, 324–334.
Ganiyu S.O., Martínez-Huitle C.A., Rodrigo M.A. Renewable energies driven electrochemical wastewater/soil decontamination technologies. Appl. Catal. B 2020, 270, 118857.
Otabaev A. Uzbekistan's green energy revolution. Qatar Tribune, 2023.
Asian Development Bank. Floating solar potential in Central and West Asia. Asia Clean Energy Forum, 2018.
World Bank. Let the Water Flow: Improved Irrigation to Help Farming Communities in Karakalpakstan. 19 June 2018.
Barbón A., Aparicio-Bermejo J., Bayón L., Georgious R. Floating photovoltaic systems coupled with pumped hydroplants under day-ahead electricity market conditions: Parametric analysis. Electronics 2023, 12, 2250.
The effect of transitioning from diesel to solar photovoltaic energy for irrigation tube wells on annual groundwater extraction in the lower Indus Basin, Pakistan. J. Agric. Food Res. 2025.
Sontake V.C., Kalamkar V.R. Solar photovoltaic water pumping system – A comprehensive review. Renew. Sustain. Energy Rev. 2016, 59, 1038–1067.
Sevilla-Camacho P.Y. et al. Optimizing method for photovoltaic water-pumping systems under partial shading and changing pump head. Clean Technol. 2024, 6, 732–749.
Wang H., Lei X., Khu S.-T., Song L. Optimization of pump start-up depth in drainage pumping station based on SWMM and PSO. Water 2019, 11, 1002.
