The paper is devoted to the proposal of a method for making managerial decisions on the replacement of production assets of TPPs in conditions of insufficient statistical data on failures and changes in the technical state of an equipment. It is proposed to use a probabilistic method to predict the period of replacement of production assets, based on the formation of a hypothesis about the law of distribution of equipment failures and its reaching the limit state, which determines the stock of possible operating time of a production asset. As an economic criterion for the period of replacement of a production asset, the use of an indicator of production profitability is considered, the advantage of which is the ability to make a decision to change equipment before the expiration of the life resource in the event of an unsatisfactory economic result of its operation, which is critical in solving the problem of ensuring the economic sustainability of TPPs. In the absence of an investment resource for the replacement of a production asset, it will be possible to recommend the conservation of an ineffective asset, which will minimize economic losses.