Policymakers and electricity suppliers are pursuing systematic strategies to install smart meters, replacing traditional meters in households, to improve the functioning of the smart grid and help consumers save energy by accessing detailed, real-time feedback on their energy consumption. Drawing on Self-Determination Theory, this paper develops a model of the process of consumer disempowerment associated with smart meter-induced data vulnerability. This process ultimately leads to the erosion of consumers' internalization of energy transition goals through the mediation of their perceived competency in using the device. Several aspects of electricity supplier behavior that could reduce the negative effects of smart meter-induced data vulnerability are explored, including managing data transparency in a relational way, ensuring fairness in the exchange with the customer, and avoiding pricing personalization based on the customer's private data. A quantitative survey conducted in France validated this model. Overall, this study contributes to the literature on customer data vulnerability and enriches the understanding of smart meter acceptability by identifying potential drawbacks of feedback-based smart devices for sustainable consumption. It also outlines how companies should engage in ethical practices when deploying smart technologies.