(19)

(11)

EP 4 555 537 A2

(12)

(43) Date of publication: 21.05.2025 Bulletin 2025/21 (21) Application number: 23947809.2 (22) Date of filing: 07.07.2023

(51) International Patent Classification (IPC):  G21C 19/00(2006.01) G21F 5/00(2006.01) (52) Cooperative Patent Classification (CPC): G21C 19/00; G21C 19/19; G21C 19/20; G21C 19/24; G21F 5/00; G21C 19/32; G21C 19/07 (86) International application number: PCT/US2023/069839 (87) International publication number: WO 2025/053854 (13.03.2025 Gazette 2025/11)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC ME MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA Designated Validation States: KH MA MD TN (30) Priority: 12.07.2022 US 202217863346 (71) Applicant: TerraPower, LLC Bellevue, WA 98008 (US)	(72) Inventors: TRUAX, John E. Bellevue, Washington 98008 (US) MCWILLIAMS, Trevor R. Bellevue, Washington 98008 (US) (74) Representative: D Young & Co LLP  Briton House Briton Street Southampton SO14 3EB Southampton SO14 3EB (GB)