1 / 11

Tritium Breeding Requirement in Next Step Fusion Nuclear Facility (FNF)

Tritium Breeding Requirement in Next Step Fusion Nuclear Facility (FNF). Mohamed Sawan University of Wisconsin-Madison Mohamed Abdou UCLA With input from Scott Willms- LANL FNST Meeting at UCLA August 12-14, 2008. Objective.

orestes-kristopher
Download Presentation

Tritium Breeding Requirement in Next Step Fusion Nuclear Facility (FNF)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Tritium Breeding Requirement in Next Step Fusion Nuclear Facility (FNF) Mohamed Sawan University of Wisconsin-Madison Mohamed Abdou UCLA With input from Scott Willms-LANL FNST Meeting at UCLA August 12-14, 2008

  2. Objective • Determine the required TBR in the FNF as a function of fusion power and available external tritium supply • TBR determined for three options • Required FNF TBR to ensure it does not run out of tritium fuel during its lifetime • Required FNF TBR to ensure that 5 kg of tritium is available at end of ITER and FNF operation for startup of DEMO • Required FNF TBR to ensure that 10 kg of tritium is available at end of ITER and FNF operation for startup of DEMO • Assume that ITER has priority over FNF for using external tritium supply from CANDU reactors

  3. Projected World-Wide CANDU Tritium (from Scott Willms, LANL)

  4. External Tritium Supply Available for FNF(from Scott Willms, LANL) • Assumptions: • 2016 ITER start • 2 kg working inventory that builds up over 2 years preceding DT operation • At end of 20 ITER operation half of working inventory lost to waste

  5. FNF Assumptions • 2021 FNF start • 1 year HH followed by 1 year DD operation • 3 years DT operation at 10% availability followed by 10 years DT operation at 30% availability • Fusion power in the range 50-400 MW considered • A tritium inventory is maintained at all time during DT operation to cover hold-up in chamber components, tritium processing system, and needed reserve • This working inventory is assumed to be 0.4 kg at 100 MW fusion power (scaling from ITER) • Working inventory scales linearly with fusion power and builds up over the 2 years preceding DT operation • At end of 15 year FNF operation half of the working inventory is lost to waste with the rest added to supply available for DEMO • Tritium burn rate is 55.6 kg/GWy • Tritium decays at rate of 5.5% per year

  6. Total External Tritium Supply Required by FNF Has Strong Dependence on TBR and Pf

  7. Tritium Inventory Available for DEMO at End of ITER and FNF Operation Depends Strongly on TBR in FNF

  8. Required TBR in FNF • TBR required to ensure that FNF does not run out of tritium supply during its operation increases as the fusion power increases • Incremental TBR required to provide a given additional tritium for DEMO is larger for low fusion power FNF

  9. How Does FNF Start Date Affect Tritium Supply? • With 2021 FNF start, both ITER and FNF end operation at same time and FNF is competing with ITER for tritium supply for all of its lifetime • With 2026 FNF start, FNF is the sole fusion user of available external supply for 5 years following ITER which has a slight net increase (0.2 kg/y Canada + 0.4 kg/y Korea – 0.1 kg/y non-fusion use – decay) • With delayed FNF start, cumulative tritium use in FNF at end of ITER operation is reduced • Without adequate TBR, delay of FNF start by 5 years results in FNF running out of tritium supply faster (for 0.5 TBR, FNF runs out of T after 13 years for 2021 start and after 10 years for 2026 start)

  10. Required TBR in FNF Slightly Affected by Start Date • Delay in FNF start results in slight reduction in required TBR • This is due to reduced cumulative amount of tritium used in FNF at end of ITER and availability of tritium resources in the 5 years after ITER for FNF without competition from ITER

  11. Conclusions • With the limited external supply and taking into account ITER operating schedule, any next step FNF should provide significant part of its tritium need • Delay of ITER makes the problem worse with higher required TBR in FNF • With available external tritium supply, a small fusion power and a modest TBR are required for FNF to have enough tritium for its operation • Another part of FNF mission is to provide the initial tritium inventory needed for startup of DEMO. This increases the required TBR in FNF. Incremental TBR required to provide a startup tritium inventory for DEMO is larger for low fusion power FNF and large initial startup inventory for DEMO (significantly greater than 5Kg) • To achieve this mission, FNF can have a TBR that increases with time with possible extension of its operation at a higher TBR

More Related