While energy consumption is necessary to support people’s everyday lives in a material and instrumental sense, the ways in which energy is used are also constitutive of ways of life and of identities. The Energy Biographies project at Cardiff University has used biographical narrative interviews and multimodal methods across four case sites in the UK to investigate this constitutive meaning of energy consumption, and its implications for attempts to reduce energy demand. Our data demonstrates the importance of emotional attachments to practices and technologies that consume energy, and the ways in which these attachments support valued identities, particularly when people undergo difficult lifecourse transitions. We show how a biographical approach can help us appreciate the ways in which ethical and moral conflicts emerge out of everyday energy consumption, not just around the priorities accorded to different values (like convenience, cost, comfort and luxury) but around what are in effect competing ethical frameworks used by people to guide them in balancing their attachments, and thus in determining how to use energy (including e.g. caring commitments to others, the costs and benefits of using energy, the plurality of values that make up a ‘good life’, or deontological rules). We thus show how qualitative biographical approaches can reveal the ethical investments and conflicts that are embedded in the thick texture of everyday life, and how the ethical significance of energy in the everyday lies in the diverse ways in which it comes to matter to us through the lifecourse.