Slovenian nuclear operator GEN Energija has published two technical feasibility studies for the EPR and AP1000 reactors with respect to the JEK2 project for a new NPP. The JEK2 project is for a plant with up to 2400 MWe capacity to be located adjacent to the existing 696 MWe Krško NPP owned and operated by Nuklearna Elektrarna Krško, which is jointly owned by Croatia’s Hrvatska Elektroprivreda (HEP Group) and GEN Energija.
Slovenia had been due to hold a referendum on new nuclear in November 2024, but it was cancelled amid a political scandal. Prime Minister Robert Golob, however, remains committed to holding a referendum before a final investment decision is taken. A final investment decision is expected in 2029, with construction beginning in 2033 and commercial operation in 2041.
The JEK2 project team, had originally been in discussions with potential nuclear power plant providers EDF, Korea Hydro & Nuclear Power (KHNP) and Westinghouse. However, KHNP withdrew from the process in January and feasibility studies were then requested from Westinghouse and EDF. JEK2 has now published the technical performance studies, which were subsequently conducted for EDF’s EPR or the EPR1200 and Westinghouse’s AP1000, noting that both proved to be technically feasible for the JEK2 location.
Vinko Planinc, Head of the Sector for New Nuclear Facilities at GEN Energija, said the studies confirm that the designs allow for safe and efficient placement in the existing environment.
The technical studies concluded that the EPR and AP1000 reactor designs are suitable for the selected JEK2 location and enable safe and efficient placement in the proposed location. “Minor adjustments and more detailed analyses will be needed in certain areas.”
Both suppliers estimate that their standard reference power plant with minor adjustments is suitable for the JEK2 location: the EDF reference power plant is Flamanville 3, and the Westinghouse reference power plant is Vogtle 4. They believe they are able to meet the requirements of nuclear regulation and legislation.
Both providers took into account the request for inherent flood safety and earthquake security. However, the two reference plants are designed for lower seismic loads than required for JEK2. As part of the study, both companies took into account the higher values for the location in Krško and estimated that the installation of a standard power plant would be possible with minor adjustments based on additional more detailed analyses.
The two suppliers both offer a power plant with project life of 60 years with possible extension to 80 years upon fulfilment of certain technical and regulatory conditions.
As to fuel and waste storage, the location provides space for wet storage of fuel elements for at least the first 15 years of operation and a storage of low- and medium-radioactive waste (NSRAO – Nizko in SrednjeRadioAktivnih Odpadkov) for at least the first 20 years of operation. Within the JEK2 enclosure, there is sufficient space for the subsequent construction of a temporary dry storage warehouse and a NSRAO for an extended life of the power plant (80 years).
Use is envisaged of cooling towers with natural circulation ensuring effective cooling with minimal impact on the environment, including the existing Krško NPP and the Sava River. This solution represents the most environmentally acceptable option, as it has the lowest carbon footprint among comparable cooling technologies. The height of the tower for the EPR is 195 metres and for the AP1000 180 metres.
JEK2 assessed risks in line with the current phase of the project, together with causes, consequences, responsibilities and mitigation strategies. It identified key risks as:
- More demanding design related to location research;
- lack of experience in the licensing and licensing process;
- infrastructure and transport arrangements;
- obtaining an experienced and trained staff; and
- development of supply chains.
As to the timetable, both providers assessed that preparatory work should be implemented before obtaining an integrated construction permit. Preparatory work includes the preparation of the terrain, transmission lines, pipelines, the construction of the necessary infrastructure for workers, etc. Also, the order of large components with a long delivery deadline should be carried out as soon as possible after the signing of the contract.
The estimated amount of investment of the JEK2 project, given by suppliers, is within the estimated value of the project study. prepared by GEN energija in 2024. These ranged from €9.314bn ($10.1bn) for a 1,000 MWe unit to €15.371bn for a 1,650 MWe unit.
Earlier, during a press conference in which GEN energija presented the business results of the previous year, Dr Bruno Glaser, Business Director of GEN energija, said public consultation and information events related to the national spatial plan for JEK2 are taking place until the end of September. In addition, a radiological study is underway as well as public procurement for a Seismic Hazard Study.
Dr Glaser added that, in addition to studies under the JEK2 project, a study was being carried out to identify possible locations for the installation of small modular reactors (SMRs) in Slovenia.
