Energy mix persistence is a defining characteristic of energy systems, for reasons including the long-lived nature of energy infrastructure and the role of local endowments. This persistence is evident in current energy-type use being strongly influenced by past use. Our analysis uses data for eight energy types and a large sample of countries, finding varying degrees of energy mix persistence. We also find evidence that carbon pricing appears to have played a key role in tilting energy mixes from coal toward renewable energy. Our estimates provide empirical support to policymakers seeking to implement carbon pricing to transition their energy systems in a lower-carbon direction.