Terra Innovatum SOLO

Project Overview

The U.S. Nuclear Regulatory Commission (NRC) is currently engaged in pre-application activities with Terra Innovatum as of January 2025. Terra Innovatum is developing its SOLO micro modular reactor design, intended to form the basis for a scalable modular energy platform from MWe to GWe-class. A SOLO unit is designed to deliver approximately 1MWe. The design features a solid heterogeneous composite moderator and is intended to accommodate both traditional zircaloy-clad low-enriched uranium (LEU) fuel or, when available, LEU+ and high-assay low-enriched uranium (HALEU) fuels. Heat removal is accomplished by helium gas which eliminates the need for water from the reactor coolant system. The reactor is intended to feature autonomous operation, on-line safeguards-by-design, and a defense-in-depth structure of radiological barriers with the intent to minimize or eliminate emergency planning zone (EPZ) requirements beyond the operational boundary.

For more information, please see the Terra Innovatum SOLO pre-application documents (NRC Docket 99902138). 

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Pre-Application Activities

Product	Type	Reference	Status
SOLO Micro Modular Nuclear Reactor Regulatory Engagement Plan, Rev 0	Regulatory Engagement Plan	ML25017A401	No review requested
SOLO Micro Modular Nuclear Reactor Regulatory Engagement Plan, Rev 1	Regulatory Engagement Plan	ML25159A006	No review requested
Design Considerations on Reactor Core (Fuel) at Nominal Conditions	White Paper	ML25159A010	Under review
Proposed Preliminary Safety Analysis Report Content and Exceptions	White Paper	ML25159A011	Under review
Transportation and Logistics for SOLO Research and Test Reactor Deployment	White Paper	ML25159A008	Under review
SOLO Micro Modular Nuclear Reactor Principal Design Criteria	Topical Report	ML25159A013	Under review