RELKO Ltd.

Domestic projects

Nuclear engineering

1. Level 1 and 2 PSA study for the units of the J.Bohunice V1 NPP

2. Level 1 and 2 PSA study for the units of the J.Bohunice V2 NPP

3. Level 1 and 2 PSA study for the Mochovce NPP

The studies are required by the Nuclear Regulatory Authority of the Slovak Republic (ÚJD SR) to demonstrate that the units of the nuclear power plants are operated in coincidence with the safety goals. The risk is calculated in the form of core damage frequency, large early release frequency of the radioactive products, etc. The PSA studies for the operating plants are regularly updated to maintain the state of the art of PSA modeling. Operation of the J. Bohunice V1 NPP was terminated in 2008. PSA activities were performed for the decommissioning process, see issue 9.

4. Risk monitors for the units of J. Bohunice V1 NPP

5. Risk monitors for the units of J. Bohunice V2 NPP

6. Safety monitors for the units of Mochovce NPP

The risk monitors are PSA applications. They are used to support the operation of the nuclear power plants. They are installed in the control rooms and evaluate the risk for different plant configurations depending on systems/components unavailabilities. In addition, the monitors are used for optimization and planning the preventive maintenance activities of the plants. The monitors of the V1 and V2 NPP were developed for use in the EOOS software (Equipment Out Of Service), which is a product of EPRI (Electrical Power Research Institute, USA), on the basis of PSA models, constructed by RELKO in the Risk Spectrum PSA code). The monitor of the Mochovce plant was developed for use in the Safety Monitor software. It is a product of Scientech (USA). At the present time the RiskWatcher software is being implemented for the units of the J. Bohunice V2 plant and the Mochovce plant.

7. Reliability database for nuclear power plants of SR

The reliability database DATAFARM, developed by RELKO, is used for reliability analysis of safety systems, PSA and optimization of maintenance for the structures, systems and components of nuclear power plants. Database is regularly updated.

8. Maintenance optimization for the structures of Mochovce NPP on the basis of RCM

RCM - Reliability Centered Maintenance is a methodology which is normally used to optimize the maintenance cost without any impact on the safety level. This methodology was used for the Mochovce NPP and it is also applied for the Bohunice V2 NPP.

9. Risk assessment for decommissioning of the V1 NPP, J. Bohunice

The operation of the Bohunice V1 plant was terminated and the decommissioning was started. RELKO performed risk assessment to support this process.

10. Risk assessment for decommissioning of the A1 NPP

The operation of A1 NPP was terminated after a severe accident. RELKO performed risk assessment for the decommissioning process.


Chemical industry

1. Risk assessment in the framework of safety report for the technologies of Slovnaft, a.s.

On the basis of PSA the risk assessment was performed for the individual technologies of the chemical plant, safety measures were proposed to reduce the risk from operation and the safety documentations were prepared.

2. Risk assessment for the technologies of Duslo Saľa

On the basis of PSA the risk assessment was performed for the individual technologies of the chemical plant and safety measures were proposed to reduce the risk from operation using the automatic safety systems.


Electrical transmission grid

1. Risk assessment for the electrical transmission grid

RELKO performed risk assessment for the Slovak electrical transmission grid – 400 kV and 220 kV - for the conditions after liberalization of the market with electrical power. The objective was to evaluate the accident sequences leading to black-out or partial black-out and to reduce the risk.

RELKO Ltd., Račianska 75, P.O.Box 95, 830 08 Bratislava