Status and future prospects of nuclear industry development in Bulgaria

This paper presents a study of nuclear energy development in Bulgaria and its contribution to the country 's energy sector. Current status and future prospects of the nuclear power industry have been discussed. Currently, two 1000 MW nuclear power units - Units 5 and 6 with WWER-1000 reactors are in operation at Kozloduy NPP site. Nuclear energy is one of the main pillars of the electricity producing sector with 32, 6 % of current national energy mix. Energy strategy and vision for the development of the power sector in Bulgaria envisage nuclear energy to be supported institutionally as a promising resource for generation of emission -free electricity and to ensure a sustainable energy mix. Extending the operational lifetime of the available capacities, as well as, the construction of new nuclear capacities have been considered to be of strategic importance for preserving energy security, reducing greenhouse gas emissions and reducing dependence on imports of energy resources in a cost-effective and competitive manner. In addition, this investigation is focused on the efforts that have been invested toward current nuclear reactors lifetime extension, thermal power uprate and diversification of fresh nuclear fuel supplies, as well as, construction of new nuclear capacities to ensure the future development of the nuclear industry in Bulgaria. Some key drivers and challenges in nuclear power sector for future development were analysed. Large size nuclear reactors and SMRs in Bulgarian context were considered and the outcomes indicates that SMRs and large reactors generation III/III + should not be opposed but SMRs could be considered as a complementarity technology to the existing large-scale reactors. Many of the currently developed SMRs conceptual designs meet the expectations for Generation IV reactors safety level but in-depth knowledge of the specific technology is required to assess and ensure safety in accordance with the Bulgarian regulatory framework which is oriented towards light water reactors.