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Kaleidos

Artist rendering with Radiant and logo above the reactor design with the primary heat exchangers, helium circulators, control drum, core, and vessel shell pointed out.


Project Overview

The U.S. Nuclear Regulatory Commission (NRC) is currently engaged in pre-application activities with Radiant Industries, Inc. (Radiant), starting in October 2022. Radiant is an El Segundo, CA company developing its Kaleidos design, a transportable micro-reactor designed to generate 3MWth and approximately 1MWe. The Kaleidos micro-reactor is a high-temperature gas-cooled reactor (HTGR) using TRISO fuel, helium gas coolant, and prismatic graphite blocks. Each micro-reactor will be fully contained in a single shipping container.

For more information, please see the Radiant pre-application documents (NRC Docket 99902106).

To subscribe to the Radiant Kaleidos email service, select Radiant Kaleidos from the Advanced Reactors list after entering your email into the GovDelivery system.

Pre-Application Activities

Product Type Reference  Status
Radiant Kaleidos Micro-reactor Pre-application Regulatory Engagement Plan – October 2023 Regulatory Engagement Plan ML23286A328 No review requested
10 CFR 70 Gap Analysis White Paper ML24115A321 ML24262A066
10 CFR Part 50 and 52 Gap Analysis White Paper ML24250A206 ML25013A338
10 CFR Part 100 Gap Analysis White Paper ML24275A261 ML25017A130
10 CFR Part 51 Gap Analysis White Paper ML24298A242 ML25023A086

Page Last Reviewed/Updated Monday, April 7, 2025