The Peculiarity of the Load Factor Variable Assumptions in Transformer Total Owning Cost Sensitivity Analyses

It's a fine business move, if prior to investing in transformers, we analytically identify the most cost-effective and energy-efficient transformer. In the total owning cost (TOC) economic analysis, it is helpful to determine how sensitive the TOC is to several factors of interest, so that the proper attention may be given to them in the decision process. Also, the manufacturers become better equipped to engineer each design to the unique situation of each customer; and the utilities are then able to compare multiple designs so as to find the optimum for their peculiar load profile. Usually, in sensitivity analyses, when the load factor (LF) is being varied to observe the trend in the ∆TOC (TOC difference between the transformer offers of interest); all other input variables of the TOC model are assumed constant. However, it is herein argued that any transformer TOC what-if analysis whose approximations wholly undermine the load pattern, to vary LF independent of the load related variables; could significantly affect the capitalization of losses, which may result in errors in judgment regarding the future uncertainties and relative importance among the input variables of the TOC model. This article is therefore an attempt to investigate this error in assumption/procedure, in the light of fostering sounder judgment towards ultimately maximizing energy savings at the lowest TOC, as long as the transformer is concerned. The sensitivity level with a comprehensive LF variation was observed in this study to at least double that obtained otherwise, and the magnitude and sense of the ∆TOC were significantly influenced by the peculiarity of the load dynamics.