The study addresses the challenge of evaluating the economic efficiency of internal investment projects in energy companies, which are often focused on innovations that do not directly generate revenue but require significant investments. The main objective of the study is to develop a universal methodology for assessing these internal projects based on economic and mathematical modeling. The research utilizes statistical and analytical methods, specifically key performance indicator (KPI) trees, along with investment and sensitivity analysis to assess the effectiveness of the proposed measures. The results include the creation of a new methodology for evaluating internal projects, along with a refined understanding of the concept of internal investment projects, which enhances decision-making in the energy sector.