[en] The HTR offers a great potential for cogeneration of heat and electricity to supply conventional process plants thus reducing the emission of greenhouse gases. The modular design and the flexibility to adapt to the customer's needs in terms of thermal/electrical power and temperature, in addition to its inherent safety features makes the HTR a promising candidate for cogeneration applications. The coupling to a conventional process plant has to be designed to meet the requirements of power and temperature demand, the distance between the nuclear and the conventional plant and its safety requirements. Several countries such as China, the US, Japan and Korea are investigating the use of an HTR for cogeneration. The European Commission is supporting relevant activities through funding of related projects. (orig.)

[en] An increasing attention has to be recognised worldwide on the development of High-Temperature Reactors (HTR) which has started in Germany and other countries in the 1970ies. While pebble bed reactors with spherical fuel elements have been developed and constructed in Germany, countries such as France, the US and Russia investigated HTR concepts with prismatic block-type fuel elements. The concept of a modular HTR formerly developed by Areva NP was an essential basis for the HTR-10 in China. A pebble bed HTR for electricity production is developed in South Africa. The construction is planned after the completion of the licensing procedure. Also the US is planning an HTR under the NGNP (Next Generation Nuclear Plant) Project. Due to the high temperature level of the helium coolant, the HTR can be used not only for electricity production but also for supply of process heat. Including its inherent safety features the HTR is an attractive candidate for heat supply to various types of plants e.g. for hydrogen production or coal liquefactions. The conceptual design of an HTR with prismatic fuel elements for the cogeneration of electricity and process heat has been developed by Areva NP. On the European scale the HTR development is promoted by the RAPHAEL (ReActor for Process heat, Hydrogen And ELectricity generation) project. RAPHAEL is an Integrated Project of the Euratom 6th Framework Programme for the development of technologies towards a Very High-Temperature Reactor (VHTR) for the production of electricity and heat. It is financed jointly by the European Commission and the partners of the HTR Technology Network (HTR-TN) and coordinated by Areva NP. The RAPHAEL project not only promotes HTR development but also the cooperation with other European projects such as the material programme EXTREMAT. Furthermore HTR technology is investigated in the frame of Generation IV International Forum (GIF). The development of a VHTR with helium temperatures above 900 C for the cogeneration of electricity and process heat which is one of the six selected advanced fission reactor concepts is a long term goal of Generation IV activities. Worldwide programmes and projects prepare the HTR/VHTR for its future role of an attractive supplier of electricity and process heat as an important contribution for a sustainable carbon dioxide (CO2) reduced power generation. (orig.)

[en] The FP6 RAPHAEL Integrated Project on V/HTR technology concluded in April 2010 after 5 years of successful performance. 35 partners from 10 Member States, an overall budget above 18 MEUR and about 170 key deliverables are some important figures of the project. RAPHAEL provides results in seven V/HTR technology areas: core physics, fuel, fuel cycle back end, materials, components, safety and system integration covering the major systems and components of a V/HTR. Major highlights include design, fabrication and testing of innovative helium components, improved fuel fabrication and fuel and materials irradiation, and safety testing and PIE of irradiated fuel. In the area of coupled reactor physics and core thermo fluid dynamics, benchmarks have been performed on core safety experiments on the AVR and HTR10 high temperature test reactors, and on the HFR EU1bis fuel burn-up experiment. The fuel cycle back-end activities cover characterisation of V/HTR-specific waste, disposal behaviour and conditioning and spent fuel performance modelling. The materials activities comprise vessel and high-temperature materials, the latter work in collaboration with EXTREMAT, and graphite irradiation and characterisation. Safety and licensing assessments of a V/HTR, and the system integration aspects with respect to plant reference data and R and D results complete the comprehensive scope of RAPHAEL. Selected results will be made available as Euratom input for exchange within the GIF VHTR projects in negotiated procedures. Two advisory groups (safety-SAG and industrial users-IUAG) accompanied the project and provided valuable input regarding adjustment of concept specifications. The recommendations of the Industrial Users Advisory Group, including major end-users, are used as input to EUROPAIRS, an FP7 support action aiming at integrating end-users into the R and D process towards a demonstrator for cogeneration. To address the key issue of knowledge transfer, RAPHAEL conducted three Eurocourses, with support of the IAEA, to transmit V/HTR physics and technology to young engineers and students. Furthermore, RAPHAEL was regularly present in conferences and has issued numerous technical publications. RAPHAEL executed intensive international collaboration mainly in the areas of materials and fuel, in particular with Korea, and in safety. In addition, its representation and contribution was often requested in collaboration initiatives of Euratom with Russia and China, and in workshops organised by IAEA.

[en] Summary report on 2 out of 12 sessions of the Annual Conference on Nuclear Technology held in Berlin, 14 to 16 May 2013: - Fusion technology (Section 9), and - Radiation protection (Section 11). The Sessions Reactor physics and methods of calculation (Section 1), Thermodynamics and fluid dynamics (Section 2), Safety of nuclear installations - methods, analysis, results (Section 3), Radioactive waste management, Storage (Section 5), Operation of nuclear installations (Section 6), New build and innovations (Section 7), Decommissioning of nuclear installations (Section 8) and Education, Expert knowledge, Know-how-transfer (Section 12) have been covered in atw 8/9 to 12 (2013). The other sessions (Front end of the fuel cycle, fuel elements and core components; and Energy industry and Economics) will be covered in further issues of atw. (orig.)

[en] The overall dimensions of the ITER Tokamak and the particular assembly sequence preclude the use of conventional optical metrology such as mechanical jigs and traditional dimensional control equipment used for the assembly of smaller, previous generation, fusion devices. This paper describes the state of the art of the capabilities of available metrology systems, with reference to the previous experience in fusion engineering and in other industries. Two complementary procedures of transferring datums from the primary datum network on the bioshield to the secondary datums inside the VV with the desired accuracy of about 0.1 mm is described, one method using the access directly through the ports and the other using transfer techniques, developed during the co-operation with ITER/EFDA. Another important task described is the development of a method for the rapid and easy measurement of the gaps between sectors, required for the production of the customised splice plates between them. The results from a practical, full-scale demonstration of the methodologies used, using the proposed equipment, is described. This work has demonstrated the feasibility of achieving the necessary accuracies for the successful construction of ITER

[en] The development of future fusion power plants will face similar development issues as future generation of fission plants in order to achieve the goals of technical feasibility and operability. Except for plasma physics, the major challenges for fusion reactors are in the areas of materials development for the heat source structures (plasma facing material for fusion and materials for the fission core) and design of cooling systems for high efficiencies. Helium cooling systems have been proposed for both future fusion plants and advanced fission reactors, in particular those for GEN IV programme. They offer the potential of high efficiencies in combination with advanced high-temperature resistant materials. Therefore, synergies for fusion and fission reactor development could be realized for development in these two areas. For example, the testing of major components of the helium cooling systems for the two power plant systems, as well as the non-nuclear testing of materials, could be possible within common test loops in which different test sections will have to be integrated. The identification of possible synergies in the relevant R and D programmes should be endorsed to minimise the development effort for future power plants. However, the assumed time schedules for the realisation of future fusion and fission reactors have to be taken into account

[en] The sections of the contribution are as follows: Achievements and future R and D needs in baseline technologies (Fuel and fuel cycle; Materials and components - reactor vessel, intermediate heat exchanger, graphite internals; Safety; Computer code qualification; Waste management; Education and training; International dimension of the European R and D); Towards application; and The path forward (P.A.)

[en] Developers of High Temperature Reactors (HTR) worldwide acknowledge that the main asset for market breakthrough is its unique ability to address growing needs for industrial cogeneration of heat and power (CHP) owing to its high operating temperature and flexibility, adapted power level, modularity and robust safety features. HTR are thus well suited to most of the non-electric applications of nuclear energy, which represent about 80% of total energy consumption. This opens opportunities for reducing CO₂ emissions and securing energy supply which are complementary to those provided by systems dedicated to electricity generation. A strong alliance between nuclear and process heat user industries is a necessity for developing a nuclear system for the conventional process heat market, much in the same way as the electronuclear development required a close partnership with utilities. Initiating such an alliance is one of the objectives of the EUROPAIRS project just started in the frame of the EURATOM 7. Framework Programme (FP7) under AREVA coordination. Within EUROPAIRS, process heat user industries express their requirements whereas nuclear industry will provide the performance window of HTR. Starting from this shared information, an alliance will be forged by assessing the feasibility and impact of nuclear CHP from technical, industrial, economical, licensing and sustainability perspectives. This assessment work will allow pointing out the main issues and challenges for coupling an HTR with industrial process heat applications. On this basis, a Road-map will be elaborated for achieving an industrially relevant demonstration of such a coupling. This Road-map will not only take into consideration the necessary nuclear developments, but also the required adaptations of industrial application processes and the possible development of heat transport technologies from the nuclear heat source to application processes. Although only a small and short project (21 months), EUROPAIRS is of strategic importance: it will generate the boundary conditions for a rapid demonstration of collocating HTR with industrial processes as proposed by the European High Temperature Reactor Technology Network (HTR-TN). (authors)

[en] Ten years ago, the European High Temperature Reactor (HTR) Technology Network (HTR-TN) launched a programme for developing HTR Technology, which expanded so far through 4 successive Euratom Framework Programmes. Many projects have been performed - in particular the RAPHAEL project in the 6th Euratom Framework Programme and presently ARCHER in the 7th - in line with the Network strategy that identified cogeneration of process heat and power as the main specific mission of HTR. HTR can indeed address the growing energy needs of industry presently fully relying on fossil fuel combustion with a CO₂-lean generation technology, thanks to its high operating temperature and to its unique flexibility obtained from its large thermal inertia and its low power. Relying on the legacy of the former European leadership in HTR technology, this programme has addressed specific developments required for industrial process heat applications and for increasing HTR performances (higher temperatures and fuel burn-up). Decisive achievements have been obtained concerning fuel manufacturing and irradiation behaviour, key components and their materials, safety, computer code validation and specific HTR waste (fuel and graphite) management. Key experiments have been performed or are still ongoing: irradiation of graphite, fuel and vessel materials and the corresponding post-irradiation examinations, safety tests and isotopic analyses; thermal-hydraulic tests of an Intermediate Heat Exchanger mock-up in helium; air ingress experiments for a block type core, etc. Through Euratom participation in the Generation IV International Forum (GIF), these achievements contribute to international cooperation. HTR-TN strategy has been recently integrated by the 'Sustainable Nuclear Energy Technology Platform' (SNE-TP) as one of the 3 'pillars' of its global nuclear strategy. It is also in line with the orientations and the timing of the 'Strategic Energy Technology Plan (SET-Plan)' for the development of CO₂-lean energy technologies, and thus strengthens the nuclear option in a future European energy mix. Nuclear cogeneration for industrial process heat applications is a major innovation and a major challenge, requiring large-scale demonstration to prove its industrial viability. To enable demonstration, it is necessary not only to develop an appropriate nuclear heat source, but also to develop coupling technologies and to adapt industrial processes to the coupling with a HTR. This requires a close partnership between the conventional and the nuclear technology holders as the base of a Nuclear Cogeneration Industrial Initiative. Recently the project EUROPAIRS initiated by HTR-TN together with process heat user industries has set the bases of such a strategic partnership.

[en] Summary report on these 5 - out of 11 - Sections of the Annual Conference on Nuclear Technology held in Hamburg on May 27-29, 2008: - Reactor Physics and Methods of Calculation - Thermodynamics and Fluid Dynamics - Safety of Nuclear Installations - Methods, Analysis, Results - Front End and Back End of the Fuel Cycle, Radioactive Waste, Storage - Fusion Technology. Other Sections will be covered in reports in further issues of atw. (orig.)