Consulting-Specifying Engineer, Jan./Feb. 2014, by John Yoon, PE, LEED AP.

"A variable frequency drive (VFD) often is specified to save money by reducing energy consumption in pumps, fans, compressors, or any other motor loads that may be found in a typical building. These best practices will provide the engineer with information on how to specify a VFD to meet load conditions while achieving efficiency."