The City of Benson produces its water required for irrigation, fire-fighting and domestic water use from different wells located in its territory. Currently, the main system that provides potable water to the City consists of 5 wells. The irrigation pumps include Ball Park (Lions Park), and golf course wells. Also, airport water semi-public system includes east airport and west airport wells. The City provides water service to approximately 5,105 residents, parks, library, school, airport and golf course.
During the analysis, it was realized that the five well pumps at the City are operating at low overall plant efficiencies. Process equipment like pumps lose efficiency over time due to normal equipment wear & tear. In addition, equipment efficiency is also affected by system conditions, and how far off they are from equipment design conditions. The existing operation of the pumps indicated that their OPEs were around 18.5%-50.7%.
The proposed Energy Efficiency Measures to overcome the inadequacies caused by the unfavorable operating conditions were:
Pump Efficiency Improvement: This measure targets improving the Overall Plant Efficiency of the well.
Well Pump Sequencing and Pipeline Extension: This measure adjusts the sequence of pumping operation and shifts production from Whetstone Well to 291 Well.
VFD Set-Point Optimization: This measure resets VFD set-point of the well.
The proposed three measures resulted in electricity savings of $31,101 per year, whereas the overall simple payback to implement the project was 7 years.