Tecnatom (Spain)

Abstract NPHyCo (Nuclear Power and Hydrogen Cogeneration) is an EU research project dedicated to the production of hydrogen from nuclear power. The project is funded by the EU’s Euratom Research & Training program (2021–2025) dedicated to nuclear research and innovation. NPHyCo started in the Autumn of 2022 and will last for two and a half years. The EU hopes to fully decarbonize its economy by 2050 [1]. One of the solutions being put forward is hydrogen. Nevertheless, to date most of the hydrogen produced in Europe comes from fossil fuels [2]. So the question is how to increase the production of low-carbon hydrogen to ensure that enough is being produced — at an affordable cost — to meet the needs of hard to decarbonize sectors, such as industry? The article presents the structure of the project and the results achieved so far by the different working groups of the NPHyCo project, such as concept, technology, economics, licensing, implementation, selection of a suitable location for the hydrogen production plant (HPP) and communication. Particular attention is paid to the nuclear power plant (NPP) modification in the case of a hydrogen facility construction, its connection to the NPP resources and NPP safety assessment. The first results regarding Ukrainian NPPs were presented in [3], but since then new results have been obtained, which are presented in the next sections. Since the largest scope of information was collected for Ukrainian NPPs we use the Rivne NPP (RNPP) for the best tuning of all universal models in WP3, WP4 and WP5. Therefore, the results for this NPP in particular are presented below.

The mechanisms of transmission and management of knowledge are mostly created by maintenance and exploitation activities of large buildings and industrial facilities, but they are poorly studied due to the difficulty capturing themas they belong to tacit knowledge gained by the experience of the maintenance staff. These professionals are highly qualified and are accostumed to solving technical problems even under pressure. The loss of these professionals means losing also an important asset of the company. This article will tackle the importance of the factors that influence knowledge management (KM) in maintenance engineering and its barriers and facilitators. The research is carried out by qualitative investigation on maintenance staff of an industrial company.

Modern grid codes attempt to unify the existing standards developed by various national and international organizations, implemented from different utilities and generator manufacturers. This evolution of new grid code practices is associated with increasing interoperability of different power systems across borders. This paper compares existing regional network codes for requirements for grid connection applicable to all generators regarding their compliance with the newly formulated code by the European network of transmission system operators for electricity (ENTSO-E). Furthermore, it studies the impact of the unified ENSTO-E codes on the fault-ride-through capability of nuclear power plants (NPP) under extended operating voltage and frequency ranges. The analysis is performed on the typical 1000MW NPP under different voltage and frequency critical ranges and shows that extending the voltage fluctuation below 0.9 pu could affect NPP reliability.

Angra-1 Nuclear Power Station (Westinghouse PWR-600 MW, 2 loops) started commercial operation in 1985, being property of Eletronuclear, subsidiary of Eletrobras in Brazil. Angra-1 has been preparing the necessary measures to renew the operating license and to apply for a lifetime extension up to 60 years. Among the many activities to perform, there are some related to fulfilling the requirements of the Brazilian regulator, the CNEN. These include requirements related to Human Factors Engineering (HFE) that included the preparation of a Chapter 18 of HFE, to become part of the plant’s Final Safety Analysis Report (FSAR). In the framework of the Instrument for Nuclear Safety Cooperation (INSC), created and funded by the European Union (EU) to enhance nuclear safety world-wide, cooperation activities between the EU and the Government of Brazil were set up in 2009. One of the INSC projects funded was to support the Brazilian nuclear operator of Angra-1 in the field of HFE. In 2010, the implementation of the project was awarded to a consortium lead by Tecnatom for performing a HFE Safety Evaluation to the plant and to provide support for preparing this Chapter 18. For this Project a specific methodology was developed for the execution of the Safety Evaluation. The methodology has been developed for evaluating — from the HFE viewpoint — a plant in operation, from the beginning of commercial operation until nowadays, including the design modifications performed to date. The obtained results have been used for developing the aforementioned Chapter 18. The main results of the Project Execution have been: 1. The developed methodology has made it possible to perform a comprehensive HFE evaluation of Angra-1, including the analysis of Post-TMI requirements, the design included in the current FSAR, the existing Angra-1 procedures and the verification of the current Main Control Room. 2. Technical support has been provided to Angra-1 for the preparation of Chapter 18 of the FSAR, following the structure of NUREG-0711, and using the results of the HFE Safety Evaluation. 3. An Action Plan has been developed for identifying and addressing in the future all those deficiencies found during the HFE Safety Evaluation, as well as those activities that are the consequence of the new FSAR Chapter 18.

A set of standard surveillance programs for monitoring the design life of reactor pressure vessels (up to 40 years of operation) has been analyzed. In view of the improved test methods and embrittlement evaluation procedures, the necessity has been shown of introducing modifications in the present surveillance programs aiming at a more precise reactor pressure vessel integrity evaluation facing a possible service life of 60 years. Service life predictions are performed for reactor pressure vessels, based on the available surveillance data, reconstituted Charpy specimens, and Master Curve testing.

A new fibreoptic reflectometric technique for the automatic detection and measurement of surface cracks is proposed, described and analysed. A relationship between the system output image and the surface crack distribution is obtained from theory and a crack measurement principle is derived. Analysis of the experimental data obtained using a first laboratory prototype has validated the proposed measurement principle. The results of a second generation prototype confirm that the technique promises to be a valuable tool in practical inspection tasks.