Software for Quantifying Energy Savings with Adjustable Frequency Drives

This paper describes software developed by Wisconsin Industrial Assessment Center (IAC) for calculations of energy savings that can be obtained by installing adjustable frequency drives (AFD). Regression models for estimating power used at different loads with and without AFD were developed. Actual data for power use is logged and the power use with the AFD is estimated. The two resulting graphs for power use are compared. The difference in the areas under the two curves is the energy savings.