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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.
Robert W. Carlsen, Paul P. H. Wilson
Nuclear Technology | Volume 195 | Number 3 | September 2016 | Pages 288-300
Technical Paper | doi.org/10.13182/NT15-138
Articles are hosted by Taylor and Francis Online.
Because of the diversity of fuel cycle simulator modeling assumptions, direct comparison and benchmarking can be difficult. In 2012 the Organisation for Economic Co-operation and Development completed a benchmark study that is perhaps the most complete published comparison performed. Despite this, various results from the simulators were often significantly different because of inconsistencies in modeling decisions involving reprocessing strategies, refueling behavior, reactor end-of-life handling, etc. This work identifies and quantifies the effects of selected modeling choices that may sometimes be taken for granted in the fuel cycle simulation domain. Four scenarios are compared using combinations of either fleet-based or individually modeled reactors with either monthly or quarterly (3-month) time steps. The scenarios approximate a transition from the current U.S. once-through light water reactor fleet to a full sodium fast reactor fuel cycle. The Cyclus fuel cycle simulator’s plug-in facility capability along with its market-like dynamic material routing allow it to be used as a level playing field for comparing the scenarios. When they are under supply-constraint pressure, the four cases exhibit noticeably different behavior. Fleet-based modeling is more efficient in supply-constrained environments at the expense of losing insight on issues such as realistically suboptimal fuel distribution and challenges in reactor refueling cycle staggering. Finer-grained time steps also enable more efficient material use in supply-constrained environments resulting in much lower standing inventories of separated Pu. Large simulations with fleet-based reactors run much more quickly than their individual reactor counterparts. Gaining a better understanding of how these and other modeling choices affect fuel cycle dynamics will enable making more deliberate decisions with respect to trade-offs such as computational investment versus realism.
