Refurbishment of a Pressurized Irrigation System in Romania: Hydraulic Analysis and a Renewable Energy Solution

This study focuses on increasing the energy efficiency and reducing the operating costs of the pressurized irrigation system in Sabangia village in the Dobrogea region of Romania. The recently modernized sprinkler-based and drip irrigation subsystems, covering 1205 ha, receive water from a canal-pumping station (PS) commissioned in the 1970s. That PS features obsolete pumps and inoperable or miscalibrated instrumentation. To select new pumps to refurbish the PS, firstly, a hydraulic analysis-based design was conducted in EPANET 2.2 to assess system needs. Secondly, a renewable energy supply solution was identified to cover the PS’s electrical energy consumption: a grid-connected Canal-Top Solar (CTS) PV power plant, where all PV panels are placed on a steel-truss structure above and along the irrigation canal, which feeds the PS. Thus, solar energy can be harvested without affecting the agricultural land. Two CTS PV power plant solutions were analyzed, with different installed capacities: one with an installed capacity of 922 kWp (PV Park A), and the other twice as large with an installed capacity of 1843 kWp (PV Park B, representing the maximum capacity that can be installed on the targeted canal). The maximum amount of energy produced by each CTS PV power plant was assessed in PVsyst V7.1.0. Each grid-connected power plant was conceptualized as a large-scale agricultural prosumer, in which electricity generation is coupled with the electricity demand of the pressurized irrigation system, while surplus electricity can be exchanged with the grid. The electrical energy balance analysis showed that the proposed refurbishment solutions are sustainable: the PS energy consumption can reach a maximum of 655.31 MWh per year, while the maximum annual energy produced can reach 1442 MWh with PV Park A, or 2891 MWh with PV Park B; the surplus green energy can be injected into the grid. The financial impact of both agricultural prosumer cases was evaluated through an analysis of Day-Ahead Market costs versus revenues.