Department of Energy Motor and Drive Assessment Identifies Energy Savings for Power Drive Systems: A Paradigm Change

Petroleum and chemical refining, along with all other process industries, utilizes many electric motors to meet power demands. This article discusses results of an assessment survey of installed motors and drives performed by Lawrence Berkeley National Laboratory (LBNL) and funded by the U.S. Department of Energy (DOE) [1]. A key finding was that there are energy savings available with the addition of adjustable speed drives (ASDs). The National Electrical Manufacturers Association (NEMA) is collaborating with the Northwest Energy Efficiency Alliance (NEEA) and Cadeo Group to develop a prescriptive process to allow for rebates for power drive systems (PDSs) consisting of a premium efficiency electric motor and an ASD. Most efficiency standards, such as NEMA MG 1 [2] or International Electrotechnical Commission (IEC) 60034-30-1 [4], today focus on the efficiency of the components, with or without an ASD, rather than focusing on energy savings through optimized process management NEMA MG 10011 [3]. Organizations are now looking at the combined energy use of the PDS, especially on variable torque loads, such as pumps, fans, and compressors that are commonplace in process industries. This is a paradigm change from component efficiency to energy savings through a PDS system.