Successful case studies of energy savings using adjustable speed drives for pumps and fans

This article presents successful case studies of energy savings using adjustable speed drives for pumps and fans in industrial facilities. In this study, we first conducted energy audits to identify adjustable speed drive (ASD) applications at industrial facilities. Then we estimated the energy savings for the applications and sought to present the results in a meaningful form. Because all the equipment considered in this study ran at constant load without any speed or flow control, instantaneous demand readings were taken prior to the retrofit. The pre-retrofit measurements served as the baseline for the equipment energy consumption. The post-retrofit energy consumptions were measured using kWh meters. The energy savings were estimated by subtracting the post-period results from those of the pre-period. In all cases, energy savings of at least 23 percent were achieved through the installation of ASDs.