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A trip abroad
Hash Hashemian president@ans.org
In my August column in Nuclear News, I reflected on the importance of ANS’s annual conferences for bringing together our nuclear community at the national level. In September, after speaking at Tennessee’s Nuclear Opportunities Workshop, I focused my NN column that month on the value of state-level conferences.
Also in September, alongside ANS Executive Director/CEO Craig Piercy, I shifted my focus to another key front in nuclear collaboration, the international stage, by attending the General Conference of the International Atomic Energy Agency in Vienna.
The timing of the IAEA’s General Conference could not have been better; it took place the same week the U.S. and U.K. kicked off a new wave of transatlantic partnerships in the nuclear sector between both government and industry. This fortuitous overlapping gave us a timely and concrete reminder of international collaboration’s unparalleled benefits.
The General Conference was an expectedly busy event. To cover as much ground as possible, Piercy and I took turns attending either the U.S. delegation meetings with other countries or the General Assembly of the IAEA, where the American Nuclear Society has a seat among other critical nongovernmental organizations.
We listened to presentations by several of the 180 IAEA member states, including, of course, the United States. Aside from ANS, the U.S. presence at the conference included U.S. Secretary of Energy Chris Wright, NRC Chair David Wright, and DOE Assistant Secretary of Nuclear Energy Ted Garrish.
U.S. representation was further bolstered by an industry delegation that included 65 participants from 32 companies, many of whom used the opportunity to report progress on their plans for the international expansion of their nuclear fleets. Meetings of that industry delegation were coordinated by the Nuclear Energy Institute.
Aside from the main conference, Piercy and I also attended the embedded meetings of the International Nuclear Society Council. INSC exists to facilitate knowledge-sharing and collaboration between 18 different member nuclear societies from around the world.
The INSC meetings within the General Conference brought together the presidents and senior members of those societies to give presentations and explore new opportunities. I made a presentation on the state of nuclear in North America, covering the latest developments and deployments in the U.S. and Canada.
This presentation emphasized the new nuclear lift in the U.S. that is being heavily supported by the Trump administration. I recapped the four executive orders issued by President Trump in May, the recent momentum at the DOE, and how these changes are capitalizing on a broader groundswell in both industry development and public support.
I also pointed out the success of our neighbor Canada in progressing on the first water-cooled small modular reactor in North America using BWRX-300 technology, which was supplied by an American firm and international partners—a perfect symbol of the value of global nuclear collaboration.
In all, I have now represented ANS at the state, national, and international levels, gaining useful insight into the work that needs to be done at each. From this vantage point, it’s clear to me that the path forward from the country to the globe is to, above all else, keep working together and supporting each other to bring about the next age of nuclear.
Rei Kimura, Shohei Kanamura, Yuya Takahashi, Kazuhito Asano
Nuclear Technology | Volume 207 | Number 11 | November 2021 | Pages 1784-1792
Regular Technical Paper | doi.org/10.1080/00295450.2020.1843953
Articles are hosted by Taylor and Francis Online.
The small modular reactor (SMR) is considered one of the important energy sources for the realization of the de-carbonated society, especially SMR types that have 10 MW or less thermal power, called a microreactor or very small modular reactor (vSMR). Toshiba Energy Systems & Solutions has initiated the development of a multipurpose vSMR as a distributed energy source since 2017 called MoveluXTM (Mobile-Very-small reactor for Local Utility in X-mark).
In the current core design, a passive reactivity control device is required from the viewpoint of passive nuclear safety and operational cost reduction. The fundamental idea of vSMR passive reactivity control devices is based on the lithium expansion module (LEM) proposed by Kambe, et al. [“Startup Sequence of RAPID-L Fast Reactor for Lunar Base Power System,” Proc. Space Nuclear Conference, (2007)], however, the LEM has some issues regarding the lithium neutron absorber, such as production costs, chemical reactivity, and tritium generation. In the present study, the In-Gd alloy is proposed as an alternative to 6Li.
The In-Gd alloy is chemically stable in the air atmosphere; additionally, indium and gadolinium have enough neutron absorption cross section without isotope enrichment. However, the density, thermal expansion, and exothermal heat characteristics are not available, which is important information from the viewpoint of neutronics and safety. Hence, the material properties in the In-Gd alloy were measured, such as temperature-dependent density and chemical reactivity. Furthermore, control rod reactivity worth was evaluated based on the measured density.
As a result, the 1 wt% gadolinium contained in the In-Gd alloy shows control rod reactivity worth that is 2.5 times greater than natural lithium. Furthermore, the uncertainty of the In-Gd alloy density has a small impact on the reactivity worth; only in the range of 78 pcm (equivalent to 1% of insertion position) in the case of the 0.1 g/cm3 perturbation of the In-Gd alloy density. In conclusion, the present study shows the advantage and feasibility of the In-Gd alloy as a liquid neutron absorber for the Indium-Gadolinium Expansion Module.
