Validation Analysis of the Power Index Calculation Procedure

To help improve energy efficiency in motor systems, the National Electrical Manufacturers Association (NEMA) developed the MG 10011-2024 Power Index (PI) Calculation Procedure, a simplified method that reflects how motors perform under typical, real-world operating conditions. Many commercial and industrial motors operate below optimal load levels, yet few use load control technologies that could significantly reduce energy use. One major barrier to adoption is the complexity of evaluating potential energy savings. The PI metric helps overcome this by making motor and drive systems comparisons easier and more accessible.

For the study, the Northwest Energy Efficiency Alliance (NEEA) and NEMA partnered to validate whether interpolated calculations instead of extensive testing yielded PI values accurately. The research involved testing 19 motor and drive systems across three independent laboratories, comparing actual performance data with interpolated results based on international standards. The findings showed strong alignment between the two, confirming that interpolation is a reliable and cost-effective method. This validation supports broader use of the PI metric, helping manufacturers and users identify energy-saving opportunities and paving the way for incentive programs that promote efficient motor technologies.