Economical Assessment of Industrial Motor Replacement from the Perspective of Life Cycle Cost Analysis

Abstract

The increasing concern about climate change has underpinned global efforts toward the reduction of greenhouse gas emissions (GHGs). In this sense, energy efficiency actions (EEAs) are interesting solutions that have been expanding over the years in the industrial sector. Replacing low-efficiency electric motors with high-efficiency counterparts is a ubiquitous action in this sense. However, they still have a high cost, making it necessary to perform a proper technical-economic analysis to determine the feasibility of the action. For this purpose, life cycle cost analysis (LCCA) has proven to be an excellent alternative for economic viability verification of EEAs because this methodology takes into account expenses throughout the entire life cycle of the project or equipment. Considering decision-making involving optimization, this work proposes a methodology to calculate the present residual value at the end of the life cycle, considering the service time of motors and the chosen study period for the project. Two case studies involving predicted theoretical situations are simulated, and the impact of service time on the replacement of a 50-CV, four-pole motor and, 40-CV in a local industry is assessed. It is observed that Net Savings are affected by the study period when replacement occurs in terms of a low-power high-efficiency motor since such action can lead to different service times. Overall, the improved LCC applied to induction motors replacement proves to be a good method for predicting the residual value, whereas the results show that different service times are necessary to maximize net savings and the residual cost in the same case.