Specific Energy




Before we talk about how we can get the most out of our Pumps and VFDs, please allow me to briefly provide some background to explain why I am passionate about this technology.


Early in my career I received a visit from an engineering firm that was allotted Federal Funds to:



  • Visit utilities

  • With their permission, conduct pump tests on major horse-powered pumps

  • Identify underperforming pumps

  • Calculate potential energy savings related to those underperforming pumps

  • Assist in making the case for these suggested repairs


They introduced me to these things called “pump curves”. It would be difficult to understate the positive impact that visit had on our utility and, in turn, my career. To this day that utility (PWC Fayetteville, NC) is internally conducting periodic pump tests and making pump repair decisions based on the “payback” period of the repair.


The visit also made us keenly aware of the potential energy savings that could be realized by ensuring pumps are run within their Preferred Operating Range (POR). Trying to execute an operational strategy to ensure POR operation was a difficult task due to the need to run multiple pump combinations as dictated by water demands. We tried to enable operators by posting combination pump curves but to no avail. The process was too cumbersome.




These issues are more important today than in previous decades, given the influx of Variable Frequency Drives (VFDs) into our facilities. It is important to know that “motor speeds are infinitely variable, pump speeds ARE NOT”.


Do we have any idea of the effect our selected pump speeds have on pump life/reliability and energy costs? We have been told/sold that “VFDs can give us multiple flow ranges and reduce energy costs”; however, we were not told of the potential negative effects on pump life and energy costs associated with running outside of POR.


It is true “VFDs can give us multiple flow ranges and reduce energy costs,” but only if associated pumps are operating within their POR. Specific Energy can ensure you are getting the value you paid for.


Specific Energy’s technology provides operators with the following insights into:


Asset Management


  • Performs routine, automated pump tests and compares pump head and efficiency curves to factory pump curves

  • Measures and tracks pump capacity and efficiency over time

  • Calculates Return on Investment (ROI) and Net Present Value (NPV) to identify which pumps are candidates for repair or replacement

  • Monitors and plots pump operating points in real-time


Pump Selection and Optimization


  • Advises operators on the absolute best pump combination available to meet a desired flow or pressure while minimizing energy consumed per million gallons (thereby minimizing energy costs)

  • Ensures operation within the pump’s POR which extends pump life


I am proud to Represent Specific Energy, an established company out of Georgetown, Texas. They have invested years of Research and Development into this technology and currently have applications running in Houston, Texas and Tulsa, Oklahoma, along with other major utilities. They are the “Real Deal”, providing a much needed technology to our industry. Please contact me if you would like to know more about the technology and check out the link below to the Specific Energy website.