Energy geographers have characterized energy as a borderland topic because of its ability to straddle and interconnect different geographic concepts and debates. In this review, we evaluate how the borderland of energy geographies has been emerging in recent years by analyzing scholarship on energy published in top geography journals and a leading energy studies journal, Energy Research & Social Science. In part 1 of our review, we evaluate how the borderland of energy geographies is evolving by mapping the geographic range of empirical studies, the processes and types of energy systems being researched and the key geographic concepts/theories engaged across the four main sub‐fields of geography. We find that energy geographies scholarship has primarily centered on the Global North, remains focused on the extractive and production phase of energy development and is evolving across and within three of the four sub‐fields of geography. Energy transitions, governance, justice, space, and landscape are key topics and concepts examined. Notable underrepresentations include a relative lack of energy geographies scholarship within physical geography, as well as limited studies that engage geographic concepts to study the transportation sector, unconventional energy development and the food‐energy‐water nexus. In part 2, we identify three broad research themes to expand the frontier of energy geographies: (a) geographies of energy knowledge production, particularly indigenous knowledge; (b) materializing energy, especially through engaging political‐industrial ecology; and (c) advancing geographic thought by critically assessing how studying energy advances/challenges/transforms core geographic concepts and debates. Collectively, our review demonstrates that energy geographies have established firm footing within and across geography. Deepening engagement with emerging trends elsewhere in geography and the social sciences will not only help to better conceptualize what a geographic perspective on energy means but will also help to make clearer sense of the rapid economic, social, environmental, and political transformations currently underway within the global energy system.