The study carries out an in-depth bibliometric analysis of how KPIs are applied across various sectors, with a particular focus on energy-related projects. The research, using a structured three-phase methodology and VOSViewer, then classified the existing literature into five key domains: Economic, Technical, Environmental, Business, and Social. The research findings showed that KPIs, while being in extensive use in economic and business contexts, still present a gap in their application for social and environmental concerns.