Energy savings and irrigation performance of a modified center pivot irrigation system

The demand for power by a center pivot irrigation system changes with tbe operating point of the system-pump curve during the opening and closing of the end gun sprinkler. The purpose of this research was to determine the possible energy savings of a `modified' center pivot irrigation system in which the operating point of the system-pump curve is held fixed. To accomplish this, several computer programs were written to simulate the design modifications of an existing center pivot irrigation system. The primary modification was the addition of auxiliary sprinklers along the center pivot lateral line which were operated when the end gun sprinkler was turned off. Both time and energy savings were possible with the modified center pivot irrigation system. The amount of energy savings was determined to be a function of the steepness of pump curve. The uniformity coefficient of the system increased with the modified design which in turn increased potential crop yield. The estimated payback period for system modification based on energy savings and crop yield increase was less than two years.