The Department of Defense (DoD) has over 10,000 facilities served by chiller and boiler systems. Induction motor-driven pumps deliver water in the chilled water, hot water, and condensing water systems in those facilities. Due to dynamic water flow in pumping systems, induction motors are often regulated by variable frequency drives (VFD). The effectiveness of pumping systems can deteriorate over their lifetime. Therefore, significant energy savings can be achieved if degraded components are identified and replaced, and faulty operations are detected and corrected on time. Unfortunately, the current assessment tools require both an electrical power meter and a shaft power meter to assess pump and motor efficiencies and cannot effectively identify the component degradation and detect faulty operations.

The project goal is to provide a low-cost assessment tool to identify degraded components and detect faulty operations effectively without using a power meter and a shaft power meter. This goal can be achieved by assessing pump and motor efficiencies in pumping systems under routine operations using common pump head and flow rate measurements plus available VFD operation data and developing the efficiency dataset to track the change of these efficiencies year by year. Specifically, the technical objectives of the demonstration are to:

1. Evaluate the initial costs and operational cost improvement of the assessment tool on a real-world DoD installation.
2. Validate the performance, i.e., the efficiency assessment, degradation identification, and fault detection, of the assessment tool using real-world DoD operating conditions.
3. Enable direct technology transfer and commercialization making the technology available across DoD.

The assessment tool will advance existing pumping system assessment tools by using commonly available measurements in DoD installations without the need for an electrical power meter and a shaft power meter. Two technologies are required for the advancement:

1. Technology I to obtain the pump-motor efficiency without a power meter: The analog output readings of VFD include the VFD output power and frequency. The VFD output power reading can substitute the power measurements of a power meter. The project team determined that the VFD output power reading has a consistent correlation with the actual VFD output power.
2. Technology II to separate the pump and fan assessments without a shaft power meter: Two uncorrelated functions are developed by the project team to express pump and motor efficiencies. Therefore, the pump and motor efficiencies can be separated from the measurable pump-motor efficiency without shaft power measurement and the performances of pump and motor can be assessed individually with high accuracy.

The assessment tool can be applied to obtain pump and motor efficiencies and build up efficiency datasets to identify and replace the degraded components and detect and correct operational faults. Thus, it can help the DoD improve the pumping system efficiency of chilled water, hot water, and condensing water systems in DoD’s 10,000 facilities served by chiller and boiler systems. (Anticipated Project Completion - 2028)