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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
Edward T. Cheng, Robert W. Conn
Nuclear Science and Engineering | Volume 62 | Number 4 | April 1977 | Pages 601-616
Technical Paper | doi.org/10.13182/NSE77-A15204
Articles are hosted by Taylor and Francis Online.
The influence of design variations, such as the percentage of structural material in a tritium breeding zone or the enrichment of lithium in 6Li, on such important controlled thermonuclear reactor parameters as the tritium breeding ratio and the total nuclear energy produced has been studied using variational techniques for two different but general blanket designs. The first design uses liquid lithium as both coolant and breeding material, while the second uses a helium coolant and a solid-lithium-bearing compound as the tritium breeder. A variational technique based on variational interpolation is the primary computational tool, and it is shown that for linear perturbations in the transport operator and for a fixed source, only forward flux calculations are required to implement the variational interpolation approach. No adjoint functions are required, while any number of response functionals can be investigated. For both blanket designs, the influence of the choice of structural material, such as stainless-steel, molybdenum, niobium, vanadium, and aluminum structures, has been studied. The role of beryllium as a neutron multiplier with a solid breeder blanket is studied, and an optimum beryllium thickness is found that maximizes the breeding ratio. The influence of using graphite or the structural material as a neutron reflector and the effect of lithium burnup are also studied. It is found that for a given percentage of structural material in the tritium breeding zones, vanadium-structured systems achieve the highest breeding ratios, while molybdenum-structured systems produce the highest value of total nuclear heating. The effects of lithium burnup are small.