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PJM queues a fusion project among 810 others
The breakdown by number of projects, share of megawatts, and generation types in PJM’s new interconnection cycle. (Source: PJM Interconnection)
On April 27, PJM Interconnection closed its first full interconnection cycle since 2022. Under a reformed application process, 811 developers submitted generation projects capable of generating 220 gigawatts of electricity. About 400 megawatts of that total share comes from Commonwealth Fusion Systems, which submitted an application for its ARC fusion power plant. This is a notable milestone for the industry: it is the first time a developer has requested to connect a commercial fusion power plant to a major grid.
Theophile Bonnet, Hunter Belanger, Davide Mancusi, Andrea Zoia
Nuclear Science and Engineering | Volume 198 | Number 11 | November 2024 | Pages 2120-2147
Research Article | doi.org/10.1080/00295639.2023.2288328
Articles are hosted by Taylor and Francis Online.
The investigation of correlations in Monte Carlo power iteration has long been dominated by the question of generational correlations and their effects on the estimation of statistical uncertainties. More recently, there has been a growing interest in spatial correlations, prompted by the discovery of neutron clustering. Despite several attempts, a comprehensive framework concerning how Monte Carlo sampling strategies, population control, and variance reduction methods affect the strength of such correlations is still lacking. In this work, we propose a set of global and local (i.e., space-dependent) tallies that can be used to characterize the impact of correlations. These tallies encompass Shannon entropy, pair distance, normalized variance, and Feynman moment. In order to have a clean yet fully meaningful setting, we carry out our analysis in a few homogeneous and heterogeneous benchmark problems of varying dominance ratio. Several classes of collision sampling strategies, population control, and variance reduction techniques are tested, and their relative advantages and drawbacks are assessed with respect to the proposed tallies. The major finding of our study is that branchless collisions, which suppress the emergence of branches in neutron histories, also considerably reduce the effects of correlations in most of the explored configurations.