U3O8$...0.00%|CCJ$...0.00%|OKLO$...0.00%|CEG$...0.00%|URA$...0.00%|URNM$...0.00%|NXE$...0.00%|U3O8$...0.00%|CCJ$...0.00%|OKLO$...0.00%|CEG$...0.00%|URA$...0.00%|URNM$...0.00%|NXE$...0.00%|
SECOND ATOMIC AGE
reactorsUnder Construction

Mark-0

**Vendor/Designer:** [[vendors/antares-nuclear]]

Key Stats

CountryUSA
StatusUnder Construction
Sources1
Tags6
UpdatedMay 10, 2026
Data QualityHigh Quality

100/100

Mark-0

Status: UNDER_CONSTRUCTION Category: SMR Country: USA USA Vendor/Designer: antares-nuclear Type: Sodium heat pipe microreactor [Sodium heat pipe microreactor](/library/wiki/technologies/Sodium heat pipe microreactor) Capacity: N/A

Overview

Mark-0 is a sodium heat pipe microreactor under construction in the USA by Antares Nuclear, supported by the DOE Reactor Pilot Program with significant funding of approximately $134 million. Its significance lies in advancing SMR technology for civilian energy applications, with a Preliminary Design Safety Assessment approved in January 2026. Specific site details and operational history remain unavailable as construction progresses.

Key Facts

Notes

DOE Reactor Pilot Program · ~$134M raised · PDSA approved Jan 2026 · 500 kWt heat pipe


Source: IAEA PRIS / reactors_canonical · Enriched by Grok Last updated: 2026-05-10

Sources

Sources (1)

Related Notes

Tags:reactorssmrmicroreactorunder-constructionantares-nuclearsodium-heat-pipe-microreactor