AMNT 2015: Opening Address
WASA-BOSS: ATHLET-CD Model
Examination by Remote Controlled Submarine
Severe Accident Management- Approaches in Europe
Safety Assessment by Complex Algorithm
Nicola Cotugno, general director of Slovakian utility Slovenské Elektrárne (SK), talks to NucNet about progress with construction of the Mochovce-3 and Mochovce-4 reactors and the role nuclear plays in the country’s energy security.
Nicola Cotugno has been working for Slovenské Elektrárne for nine years and was appointed general-director in February 2015. He graduated in mechanical engineering from the University of La Sapienza in Rome and then majored in business at the Insead business school in France.
The Annual Meeting on Nuclear Technology (ANMT) is the only one in Germany and also in Europe which is dedicated so holistically to nuclear technology and at the same time specifically promotes the international exchange of expertise.
Main topics, which have been addressed in the Opening Adress by Ralf Güldner, President of the DAtF (German Atomic Forum), are
Polina Tusheva, Frank Schäfer, Yaroslav Kozmenkov, Sören Kliem, Thorsten Hollands, Ailine Trometer und Michael Buck
Within the scope of the ongoing joint research project WASA-BOSS (Weiterentwicklung und Anwendung von Severe Accident Codes – Bewertung und Optimierung von Störfallmaßnahmen) an ATHLET-CD model for investigation of severe accident scenarios has been developed. The model represents a generic pressurized water reactor (PWR) of type KONVOI. It has been applied for analyzing selected hypothetical core degradation scenarios, considering application of countermeasures and accident management measures, during the early phase of an accident, as well as the late in-vessel phase, when the core degradation process has already begun. Possible accident management measures for loss of coolant (LOCA) and station blackout (SBO) scenarios are discussed. This paper focuses on the ATHLET-CD model development and results from selected simulations for a SBO scenario without and with application of countermeasures.
Summary report on the following Focus Session of the 46th Annual Conference on Nuclear Technology held in Berlin, 5 to 7 May 2015:
Implementing New Safety Requirements in Europe (Christian Raetzke)
The other Sessions of the Key Topics
will be covered in further issues of atw.
Elenko Tsvetkov and Jan Heinsius
Remote visual examination is one of the most important methods for non- destructive in-service inspections of primary components in nuclear power plants. It features two main advantages: the short examination duration and the fast interpretation of results.
AREVA offers operators of nuclear power plants the “SUSI 420 HD” SUbmarine System for Inspections to perform ENIQ-qualified visual examinations during outages without working on the critical path and causing any delay in the time schedule.
The system is a remotely operated manipulator equipped with a high definition camera. With a weight of only 25 kg, there is no need for a crane to put the submarine into water. More-over, nor the use of the refueling machine neither the auxiliary bridge is required. In this way the visual examination can be performed in parallel to other activities which are on the critical path.
The article takes a closer look at the essential parameters: illumination, examination distance, viewing angle, scanning speed, positioning accuracy and sizing of indications. It describes how the system can fulfill these parameters through some adaptations.
Pedro Trueba Alonso, Luis Fernández Illobre and Fernando Ortega Pascual
Almost all the existing Nuclear Power Plants (NPPs) include plans to modernize their existing Instrumentation and Control (I&C) systems and associated Human System Interfaces (HSIs), due to obsolescence problems.
Tecnatom, S.A. has been participating in modernization programs in NPPs to help them to plan, specify, design and implement the modernization of control rooms and associated I&C and HSIs. The application of Human Factors Engineering (HFE) in modernization programs is nowadays unavoidable. This is because is becoming a regulatory requirement, and also because it is needed to ensure that any plant modification, involving the modernization of I&C and HSI, is well designed to improve overall plant operations, reliability, and safety.
This paper shows some experiences obtained during the application of HFE to the modernization of these HSIs. The experience applying HFE in modernizations and design modifications show a positive effect, improving the associated HSIs, with the acceptability of the final user.
S. Hermsmeyer, L.E. Herranz, R. Iglesias, B. Reer, H. Nowack, M. Sonnenkalb, A. Stefanova, P. Chatelard, L. Foucher, E. Raimond, M. Barnak, P. Matejovic, V. Sanchez, G. Lajtha, Z. Techy, T. Lind, F. Gremme, M. Koch, A. Bujan, A. Grah, G. Pascal, P. Pla, M. Sangiorgi, M. Strucic and M. Vela Garcia
The severe accident at the Fukushima-Daiichi nuclear power plant (NPP) has led to a worldwide review of nuclear safety approaches and is bringing a refocussing of R&D in the field. To support these efforts several new Euratom FP7 projects have been launched.
The CESAM project focuses on the improvement of the ASTEC computer code. ASTEC is jointly developed by IRSN and GRS and is considered as the European reference code for Severe Accident Analyses since it capitalizes knowledge from the extensive Euro-pean R&D in the field. The project aims at the code’s enhancement and extension for use in Severe Accident Management (SAM) analysis of the NPPs of Generation II-III presently under operation or foreseen in the near future in Europe, spent fuel pools included.
The work reported here is concerned with the importance, for the further development of the code, of SAM strategies to be simulated. To this end, SAM strategies applied in the EU have been compiled. This compilation is mainly based on the public information made available in the frame of the EU “stress tests” for NPPs and has been complemented by information pro-vided by the different CESAM partners. The context of SAM is explained and the strategies are presented. The modelling capabilities for the simulation of these strategies in the current production version 2.0 of ASTEC are discussed. Furthermore, the requirements for the next version of ASTEC V2.1 that is supported in the CESAM project are highlighted. They are a necessary complement to the list of code improvements that is drawn from consolidating new fields of application, like SFP and BWR model enhancements, and from new experimental results on severe accident phenomena.
Am 4. Juni 2015 hat der Europäische Gerichtshof (EuGH) sein lang erwartetes Urteil in Sachen Kernbrennstoffsteuer gesprochen (Rs. C-5/14). Nachdem bereits der Generalanwalt im Februar dafür plädiert hatte, diese Steuer als mit dem Unionsrecht vereinbar zu bewerten, überrascht das jetzt ergangene Urteil im Ergebnis nicht. Es bestätigt die bereits vom Generalanwalt genannten Argumente, insbesondere in Bezug auf die zu verneinende Beihilferelevanz der Steuer und ihre Vereinbarkeit mit dem EURATOM-Vertrag. Doch final entschieden ist damit noch nichts. Dem 1. Akt (EuGH) folgt bald ein 2. (BVerfG). Kurz: Das Drama um die Steuer geht weiter.
The tax levied on nuclear fuel in Germany does not contravene European law. This was the conclusion of the European Court of Justice (ECJ) on 4 June 2015.
The German Hamburg Finance Court had doubted whether the country’s Nuclear Fuel Tax Act was compatible with European law. In the context of an action lodged by a nuclear power plant operator against this tax, the court had suspended the legal action and submitted various legal questions to the ECJ. The decision now taken by the ECJ is not really surprising considering that in his opinion, in February, the Advocate General had already argued that the tax was compatible.
The Federal Constitutional Court must now decide whether the German concept of excise duty is to be interpreted in accordance with the EU directive issued to harmonise these very taxes or whether there is some flexibility allowing a different decision.
Hyo Sung Cho and Tae Ho Woo
The human error is analyzed by using non-linear time flows in the case of nuclear power plants (NPPs) accidents. The decision making is performed using complex non-linear dynamical simulations. This gives multiple descriptions in any event of NPPs, which can give the better solution in the event response procedures. The time step incorporated with human error equations describes two different cases of the non-linear time flows. The parallel theory is utilized for time step changes, because time flows are different by the simulation calculation sequences variation. Comparisons bet-ween two cases can give the priority in the reliability of the event, where quantitative values show the dynamical performances in the designed event. Top events are quantified by the time step of 1.0 and 0.5. The values of time step 1.0 has higher than those of time step 0.5 in the study.
The public discussion on nuclear energy is not focused on power plant safety anymore. A globally good safety statistic and years of information activity on safety technology provided progress, even though all incidents are still discussed with great dedication. Nevertheless the field of disposal receives more prominence in public discussions since 1976; reprocessing of irradiated fuels and storage of nuclear waste follow the topic of nuclear power plants with temporary shift. During a long preparation time technical and operational know-how was gathered for both fields that is now available for use on large technical scale. For the entire disposal complex exists a comprehensive concept prepared by the federal government, which has to be put into practice together with the industry. The priority assignment for a dialogue with the public is to comprehensively inform on extend and quality of problem solutions and to highlight that even here the safety of the biological-cycle is the guiding principle for all considerations.
At the international expert conference, Annual Meeting on Nuclear Technology (AMNT 2015) in Berlin in May, there was a very welcome public admission from one of the German government’s key policymakers.
The director-general of the energy policy department at the Federal Ministry for Economic Affairs and Energy (Bundesministerium für Wirtschaft und Energie – BMWi), Thorsten Herdan, said the high level of expertise available throughout Germany’s nuclear energy industry was greatly valued at home and abroad and must be retained.
He rightly said that the country’s technical competence and know-how “will still be needed” – despite the country’s commitment to phasing out the use of nuclear at home under the politically-inspired ‘energy transition’ (Energiewende).
The nuclear energy industry’s commitment to identifying, training and nurturing a new generation of nuclear professionals is self evident. Perhaps what is needed now is for governments such as Germany’s, whether supporters of nuclear power generation or not, to do more to endorse the importance of developing nuclear expertise.
In the nuclear industry, governments will find a more than willing partner in supporting the training and education of the nuclear engineers and regulators of the future.