Energy consumption has been a prominent question in the last decade that concerns both hardware and software dimensions. Source code refactoring is a widespread activity among developers that includes a set of well-known changes to improve the code quality without impacting the functional aspects. Hence, the concern of the impact that may those changes induce on the software energy consumption is legitimate, in order to identify whether and which refactorings have a significant impact on the evolution of the energy consumption. In particular, while the state of the art investigated the impact of some specific code refactorings on dedicated benchmarks, we miss an assessment that those apply to more comprehensive and complex software. To address this threat, this paper studies the evolution of the energy consumption of 7 open-source software developed for more than 5 years. Then, by focusing on the impact on energy consumption of changes involving code refactorings, we intend to assess the effects induced by computational code refactorings. For all these software systems we studied, our empirical results report that the code refactorings we mined do not substantially impact energy consumption. Interestingly, these results highlight that i) structural code refactorings bring energy-preserving changes to the code, and ii) major energy variations seem to be related to computational code refactorings and/or functional changes.