The electric power enterprise devotes considerable attention to the reliability of power transformers particularly when it decides to either maintain these transformers or decommission them altogether from operation. Although this process has reduced the risk of transformer faults

the attendant dilemma is of excessive maintenance of transformers

or retiring them prematurely

leading to high economic waste. This paper is inspired by real-time engineering applications

and proposes an improved model to assess the economic life of power transformers. The new model offers a more efficient approach than previous methods of assessment

with a specific focus of using the annual net income as separate criteria for determining the economic indices of continuous operation

overhaul

and retirement strategies of transformers. The economic life of power transformers is divided into three sections according to different strategies to better resolve the quantification problem in this field. A case study is provided to prove the feasibility and validity of the proposed economic life model. The case study achieves the fine management goal when the electric power enterprise is required to make the maintenance and retirement strategy decision.