(19)

(11)

EP 4 816 758 A1

(12)

(43) Date of publication: 07.10.2026 Bulletin 2026/41 (21) Application number: 24790783.5 (22) Date of filing: 30.09.2024

(51) International Patent Classification (IPC):  F28D 1/00(2006.01) F22B 37/00(2006.01) G21C 1/32(2006.01) G21D 1/00(2006.01) (52) Cooperative Patent Classification (CPC): G21C 1/326; G21D 1/006; F28D 7/12; F28D 7/1638; F28D 7/1646; F28D 7/1676; F28D 2021/0054 (86) International application number: PCT/US2024/049314 (87) International publication number: WO 2025/117017 (05.06.2025 Gazette 2025/23)

(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: GE KH MA MD TN (30) Priority: 01.12.2023 US 202363605365 P (71) Applicant: TerraPower LLC Bellevue,Washington 98008 (US)	(72) Inventor: MOORE, Stephen Bellevue, Washington 98008 (US) (74) Representative: D Young & Co LLP  3 Noble Street London EC2V 7BQ London EC2V 7BQ (GB)