This work presents the conversion of a photovoltaic water pumping system (PVWPS) to its corresponding battery-based solution, while maintaining the components of the PVWPS facility and adding the power converter needed to manage the operation of a lithium-ion battery. A complete analysis of the direct PVWPS is performed based on the values obtained by the monitoring system developed for the installation. The efficiencies and performance ratios of the various elements of the facility are calculated, as well as other relevant factors (such as irradiance thresholds). The dependence of some variables on the solar resource is analyzed to model the system. A similar study is carried out in the battery-based solution and a comparative analysis of the two modes of operation is then performed to find which aspects could be improved in the battery-based solution to increase the pumping time and total daily pumped volume. The results presented demonstrate the benefits of including a battery (reduction in start/stop cycles and improved performance on cloudy days). Aspects that can be improved to make the battery-based solution more efficient and achieve better results are suggested.INDEX TERMS Photovoltaic water pumping systems, lithium batteries, battery-based pumping, water pumping, stand-alone photovoltaic system, sustainable development goals.

The development of photovoltaic (PV) technology is now a reality. The inclusion of lithium-ion batteries in grid-connected PV systems is growing, and the sharp drop in prices for these batteries will enable their use in applications such as PV water pumping schemes (PVWPS). A technical solution for the monitoring and tracking of PV systems is shown in this work, and a novel quasi-real-time monitoring system for a PVWPS with a Li-ion battery is proposed in which open-source Internet of Things (IoT) tools are used. The purpose of the monitoring system is to provide a useful tool for the operation, management, and development of these facilities. The experimental facility used to test the monitoring system includes a 2.4 kWpk photovoltaic field, a 3.6 kVA hybrid inverter, a 3.3 kWh/3 kW lithium-ion battery, a 2.2 kVA variable speed driver, and a 1.5 kW submersible pump. To address this study, data acquisition is performed using commercial hardware solutions that communicate using a Modbus-RTU protocol over an RS485 bus and open software. A Raspberry Pi is used in the data gateway stage, including a PM2 free open-source process manager to increase the robustness and reliability of the monitoring system. Data storage is performed in a server using InfluxDB for open-source database storage and Grafana as open-source data visualization software. Data processing is complemented with a configurable data exporter program that enables users to select and copy the data stored in InfluxDB. Excel or .csv files can be created that include the desired variables with a defined time interval and with the desired data granularity. Finally, the initial results of the monitoring system are presented, and the possible uses of the acquired data and potential users of the system are identified and described.

Electromagnetic and ultrasonic flowmeters are high precision devices that can measure the water flow in pressurized irrigation networks. In these networks, the inadequate installation distance of flow control valves generates upstream disturbances which will increase measurement errors and reduce the accuracy of the equipment. Therefore, estimating these errors is important to establishing the correct installation distance of the hydraulic accessories and to ensuring the metrological reliability of the flowmeters. This work proposes a numerical study using Computational Fluid Dynamics to evaluate water flow behavior in pipes and estimate measurement errors caused by gate and butterfly valves in installation configurations found at pressurized irrigation networks. The numerical simulations were made for gate (15, 50 and 75 % closed) and butterfly (open and 30º closed) valves installed three and six diameters (3D and 6D) from the flowmeters. The numerical study with three-dimensional simulation allows for evaluating the flow behavior and estimating measurement errors correctly. According to the study, the installation configurations of the gate and butterfly valves change the flow velocity profile at different positions in the pipe, generating both positive and negative measurement errors at both flowmeters. Among the tested configurations, only the butterfly valve installed 3D and 6D from the electromagnetic flowmeter ensured the measurement accuracy required by ISO 4064.

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This work focuses on the situation of the technological transition to new technologies in drip irrigation in the Valencian Community (Spain). The study covers the last decade with data from interviews to managers of Irrigation Communities in 2010 and 2018. We analyze the main technological problems in seven topics: (i) Catchment & Pumping; (ii) Storage & Regulation; (iii) Treatment & Filtering; (iv) Transport & Distribution; (v) Maneuver, Regulation & Protection; (vi) Automation; (vii) Theft and Vandalism. We also have researched the influence of the performance of the Automation system, the presence of a technician in the Irrigation Community and the use of sensors or climatic data. Results show that problems related to technological maintenance of filtering systems or automation are very common and important and they are more important in large Irrigation Communities. We have also observed that mostly large ICs are using sensors or climatic data for their irrigation schedule. We can conclude that their current situation is focused in the daily maintenance of technological problems, inherited from the first modernization processes at the beginning of 21st century. Hence, they are far away from a second stage of modernization or the smart irrigation pushed by the new advances on technology.