Improving energy efficiency in industries is imperative for sustainable transitions. This article explores the logic behind calculating energy savings from energy efficiency improvements. Based on a qualitative study of industry-research projects and policies to improve energy efficiency in Norway, the article presents different ways energy savings are estimated when assessing the viability of novel technologies. Here, energy savings are calculated as the difference in energy consumption between a proposed technology (use-case) and an alternative scenario (base-case). We discuss the heterogeneity of the chosen cases of comparison, as they are associated with a wide variety of uncertainty, contextual preconditions, estimates, and projections. Further, we trace the calculations of energy savings of one of these projects as they move from the context of research and technology assessment to official reporting. We show how the circumstances where these numbers are produced become black-boxed as the calculations are transformed and aggregated into a policy program-specific measurement “energy results” in Norway. Our findings show that the project and policy objectives and measurements point in somewhat different directions. Through this, we unpack the logic inscribed in energy savings calculations and the way these are applied to reach multiple goals.