The paper is organized as follows: first, the energy efficiency improvement scenarios related to different diffuser designs are being discussed. The next section introduces a compressor task
in a waste water treatment plant illustrating a typical end-use process for centrifugal compressors. The section also presents the resulting energy consumption and potential savings with each diffuser scenario. Based on these energy calculations, the life-cycle assessment study is conducted. Finally, conclusions of this study are given in the last section.