Adaptation of pressurized irrigation networks to new strategies of irrigation management: Energy implications of low discharge and pulsed irrigation

• Consequences of adopting new on-farm irrigation management strategies on energy consumption and electric costs in a pressurized irrigation network were analyzed.
• Reductions of emitter discharge and energy consumption or energy cost savings are not inherently related to each other.
• Pulsed irrigation in the current scenario showed an energy saving potential.

This paper analyzes the consequences of adopting new on-farm irrigation management strategies (low discharge rates, long irrigation times and high frequencies) in an existing on-demand and sectorized pressurized irrigation system in eastern Spain. The sectorized behavior of the network was analyzed using two criteria: (i) the operating sectors obtained in a first stage by arranging the hydrants depending on their altitude respecting the pumping station and (ii) the operating sectors obtained by means of an optimization process. The Simulated Annealing combinatorial metaheuristic optimization technique was employed to find the best solution. Random on-demand patterns were generated using a Montecarlo simulation. The hydraulic requirements of the network were analyzed in every scenario by the Epanet 2.0 engine. The effect on energy consumption, power requirements and energy costs was assessed taking into account the electricity tariff billing structure. It was found that reductions in emitter discharge (qe) and Energy consumption (E)-Energy Cost (EC) savings are not inherently related to each other. Certain amounts of E and EC could be saved when the number of sectors and operating time parameters were properly selected. Pulsed irrigation in the current scenario showed an energy saving potential of 10.67, 6.43 and 6.99% for power capacity, E and EC, respectively.