Enhancing water productivity in arid wheat production through nighttime center pivot irrigation with gravity-assisted energy recovery

Improving irrigation water productivity in arid farming depends on both irrigation timing and system operation. This field-scale comparative case study examined two commercial center pivot systems managed under contrasting irrigation schedules. Pivot A was operated during the day, while Pivot B was operated at nighttime and supplied from an elevated storage basin through a gravity-assisted hydraulic energy-recovery arrangement. Compared seasonal irrigation volumes, recorded operating schedules, grain yield, and irrigation water productivity between the two configurations. Seasonal applied irrigation water was 5647.36 m 3 ha⁻ 1 for daytime Pivot A and 4884.88 m 3 ha⁻ 1 for nighttime Pivot B, corresponding to 13.5% less applied water in the nighttime/gravity-assisted configuration. Grain yield was 5000 and 5714.28 kg ha⁻ 1 , respectively, and IWP was 0.89 and 1.17 kg m⁻ 3 . Each operating configuration involved one full-scale pivot, and Pivot B differed from Pivot A in both irrigation timing and hydraulic energy-supply configuration; the observed differences are best viewed as site-specific comparative evidence rather than replicated causal treatment effects.