As corner systems travel through the field, water flow requirements change
by 40% or more. You may rely on valves and regulators to control flow but
why not start by only pumping as much water as needed at the given time?
If your pump is electric, there is only one option; a variable frequency drive
VFDs (also referred to as variable speed drives) can reduce output by
controlling the motor speed (rpm) rather than having the motor work at
a constant, almost full load only to have water flow throttled by the pivot
itself. As university studies and real-life installations have indicated, a VFD
can reduce the amount of electricity (kilowatt-hours) you use in a season up
to 30%. Of course, every system is different so savings will vary.