TRANSFORMATION OF UKRAINE’S ENERGY SYSTEM: FROM NUCLEAR DOMINANCE TO A HYBRID MODEL

Abstract

The article examines the evolution of the United Energy System of Ukraine (UESU) from 1991 to the present, focusing on its economic, technical, and security transformations. It traces the main stages of development — from the post-Soviet centralized infrastructure to current processes of decentralization and integration with ENTSO-E. During the 1990s, Ukraine’s energy policy was shaped by a deep economic crisis, loss of industrial capacity, and a shift toward nuclear generation as the most stable and cost-efficient energy source. Between 2004 and 2014, Ukraine faced growing geopolitical pressure from the Russian Federation, declining efficiency of thermal power plants, and heightened energy dependence. Since 2014, amid military aggression, the country has implemented energy market reforms, enhanced system resilience, and aligned its regulatory and technical standards with those of the European Union. The emergency synchronization with ENTSO-E in 2022 marked a crucial step toward energy independence and integration into the European energy space. The paper highlights the wartime challenges of infrastructure destruction, loss of generation capacity, and the increasing need for decentralized energy solutions. In conclusion, the study substantiates the strategic relevance of a hybrid energy model combining centralized nuclear and hydro generation with decentralized renewable sources, cogeneration facilities, and energy storage systems. This model is proposed as the foundation for Ukraine’s post-war energy recovery and long-term energy security, emphasizing the importance of diversification, grid flexibility, and cross-border cooperation. The findings contribute to the broader discussion on sustainable energy transition in post-conflict economies and the resilience of critical infrastructure in conditions of hybrid warfare. The research also provides analytical insights into policy adaptation under extreme conditions and the role of European integration in stabilizing national energy governance. It underscores that the modernization of Ukraine’s energy system is not only a technical necessity but also a key geopolitical and economic priority for the country’s future development.