Enhancing energy efficiency in medium-voltage distribution networks through voltage level elevation: A technical and economic assessment

Energy efficiency in power distribution systems closely relates to technical losses, which depend on factors such as voltage level selection, conductor sizing, and equipment performance. In Brazil, primary distribution networks typically operate at voltage levels of 11.4 kV, 13.2 kV, and 13.8 kV. However, older distribution networks operate at lower voltage levels, making voltage level elevation a complex and high-risk process, especially in large urban centers with high consumer density. Given the technical and economic implications of such modifications, careful evaluation remains essential before implementation. The present work evaluates the feasibility of increasing the voltage level from 11.4 kV to 13.8 kV in a densely populated metropolitan area, with an analysis of its impact on energy efficiency and operational costs. The results indicate a discounted payback period of 6.10 years, an NPV of USD 19.33 million, an IRR of 28.60 %, and a MIRR of 18.56 %, confirming the technical and economic feasibility of the proposed approach. In addition to the economic assessment, a risk analysis quantifies the uncertainties and potential vulnerabilities associated with the voltage level increase. In all simulated scenarios, the proposal remains feasible, with the NPV ranging from USD 14.7 million to USD 23.4 million in the worst case. These results contribute to a broader understanding of the benefits and challenges involved in raising voltage levels in existing distribution networks.