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JAEA Reports

An Analytical study on Russia's civilian nuclear energy utilization

Kawasaki, Nobuchika

JAEA-Review 2025-043, 74 Pages, 2025/10

JAEA-Review-2025-043.pdf:2.45MB

Russia is one of the most advanced countries in the civilian use of nuclear energy. However, understanding the internal mechanisms of its nuclear program remains difficult due to various reasons. Therefore, this study presents a historical overview of Russia's nuclear energy utilization, fuel supply, fuel manufacturing capabilities, and concepts regarding reprocessing and the nuclear fuel cycle. From this overview, insights have been extracted and analyzed. These insights are then organized under two strategic perspectives: "Strategic diversity and continuity in developments and demonstrations" and "Diversity in utilizations and deployments," with considerations of implications for Japan, as below. Russia's nuclear energy policy strategically utilizes a variety of reactor types and fuel cycle technologies to expand nuclear power generation both domestically and internationally. Currently, nuclear power, centered on light-water reactors (VVER series), accounts for about 20% of Russia's electricity supply, and there are plans to increase this share to 25% by 2045. A wide range of reactors, from large-scale to medium and small modular reactors, are being constructed in Russia. Russia is also actively developing fast reactor technologies, and focusing on the reprocessing and recycling of spent fuel. Internationally, VVER-1200 reactors are under construction in several countries, and cooperation with China is deepening in the field of fast reactors. Notably, Russia offers an integrated, or selectively customizable, package of nuclear technology services on the international stage. These include not only reactor deployment, but also fuel supply, reprocessing, waste management, and even the provision of radioisotopes. Rather than simply exporting products or technology, Russia fosters long-term relationships and trust by flexibly responding to the conditions and needs of partner countries. For this reason, Russia promotes the technology developments in advance within the country in areas anticipated for future overseas deployment. It carefully selects target technologies and services and systematically rolls them out. This flexible strategy, combining "technological diversity" and "strategic consistency", enables cooperation with countries across various geopolitical contexts. For Japan, this strategic approach offers valuable lessons on how to engage in comprehensive international nuclear cooperation, not merely through technology exports, but through integrated approaches that encompass the entire fuel cycle, and by combining elements such as fast reactors and RI supply.

Journal Articles

A Decade of neutron diffraction study of iron hydrides

Aoki, Katsutoshi*; Machida, Akihiko*; Saito, Hiroyuki*; Hattori, Takanori

Koatsuryoku No Kagaku To Gijutsu, 35(1), p.4 - 11, 2025/03

https://doi.org/10.4131/jshpreview.35.4

Iron reacts with hydrogen to form solid solutions with body-centered cubic, face-centered cubic, hexagonal close packed, and double hexagonal close packed structures at high temperatures and high pressures. Neutron diffraction is the most powerful tool for determining the occupation sites and occupancies of hydrogen atoms dissolved in a metal lattice. Structural parameters, including hydrogen occupation sites and occupancies, are refined via Rietveld analysis for neutron diffraction data. We present our expertise in Rietveld refinement of iron hydrides accumulated over 10 years.

Journal Articles

Crystal structure and electron density distribution analyses of Nd $_{x}$ Ce $_{1-x}$ O $_{2-delta}$ for electrolyte by Rietveld/ maximum entropy method

Taguchi, Tomitsugu; Igawa, Naoki; Birumachi, Atsushi; Asaoka, Hidehito; Miwa, Shuhei; Osaka, Masahiko

e-Journal of Surface Science and Nanotechnology (Internet), 13, p.339 - 342, 2015/06

https://doi.org/10.1380/ejssnt.2015.339

Rare-earth doped ceria exhibits both ionic and electronic conductions, and those ceria with higher ratio of ionic conduction against electronic conduction is used as a solid electrolyte for solid oxide fuel cells. The electron density distributions in crystals are closely related to the electron diffusing pathway which affects the electronic conduction. In this study, we investigated the electron density distribution of doped ceria as a function of the content of Nd $_{2}$ O $_{3}$ -dopant to deduce the ratio of the electronic to ionic conduction. The crystal structure was refined with the space group, -3, which is the same as undoped ceria. Ce and Nd ions randomly occupied the 4 site and O ion the 8 site. The electron conduction pathway was distributed through the 4-8 and 8-8 sites. The relationship between crystal structural change and electron density distribution as a function of the content of Nd $_{2}$ O $_{3}$ dopant will be discussed.

Journal Articles

Neutron powder diffraction study of methane deuterohydrate by the maximum entropy method

Hoshikawa, Akinori; Igawa, Naoki; Yamauchi, Hiroki; Ishii, Yoshinobu

Journal of Physics and Chemistry of Solids, 66(10), p.1810 - 1814, 2005/10

https://doi.org/10.1016/j.jpcs.2005.07.012

Times Cited Count：5 Percentile：24.83(Chemistry, Multidisciplinary)

no abstracts in English

Journal Articles

Maximum entropy method analysis of neutron powder diffraction patterns of methane deuterohydrates

Hoshikawa, Akinori; Igawa, Naoki; Yamauchi, Hiroki; Ishii, Yoshinobu; Stern, L. A.*

Proceedings of 5th International Conference on Gas Hydrates (ICGH-5), Volume 5, p.1619 - 1626, 2005/06

no abstracts in English

Journal Articles

Temperature dependence of magnetic moment orientation in Co $_{2}$ Z-type hexaferrite estimated by high-temperature neutron diffraction

Takada, Yukio*; Nakagawa, Takashi*; Fukuta, Yasunari*; Tokunaga, Masatoshi*; Yamamoto, Takao*; Tachibana, Takeshi*; Kawano, Shinji*; Igawa, Naoki; Ishii, Yoshinobu

Japanese Journal of Applied Physics, 44(5A), p.3151 - 3156, 2005/05

https://doi.org/10.1143/JJAP.44.3151

Times Cited Count：4 Percentile：17.26(Physics, Applied)

We investigated the correlation between the thremomagnetic curve of Co $_{2}$ Z-Type hexagonal barium ferrite, Ba $_{3}$ Co $_{1.8}$ Fe $_{24.2}$ O $_{41}$ and its magnetic moment direction. The thermomagnetic curve shows two significant magnetization slumps at 540K and 680K. High-temperature neutron diffraction experiment and Rietveld analyses indicate that temperature rise from 523 to 573K makes the magnetic moments turn to the c-axis from a direction parallel to the c-plane most significantly.The change in average orientation of the magnetic moments must be induced by the disappearence of the contribution of cobalt to magnetism in this temperature.