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Janus: The Army’s Second Attempt at Fielding Microreactors

December 18, 2025 · 1 h 13 min

Show notes

In this episode of Decouple, Dr. Jeff Waksman, Principal Deputy Assistant Secretary of the Army for Installations, Energy and Environment, explains how the U.S. Army is making a second attempt at making microreactors great again. The discussion situates the Janus microreactor program in the long history of the Army Nuclear Power Program and Project Pele, highlighting why earlier small reactor deployments failed to compete with diesel and grid power even in extreme environments, and why Janus represents a fundamentally different approach.

Janus is best understood as an attempt to apply the Commercial Orbital Transportation Services model to nuclear energy, using milestone-based funding, hard downselects, and vendor replaceability to subsidize learning rather than electricity sales. The conversation explores the severe economic constraints facing one to ten megawatt reactors, the limits of the SpaceX analogy, and the unglamorous but decisive challenges of fuel logistics, waste removal, and slow nuclear learning cycles that will ultimately determine whether microreactors can ever move beyond demonstration and into durable military let alone commercial service.


Listen to Decouple on:

• Spotify: https://open.spotify.com/show/6PNr3ml8nEQotWWavE9kQz

• Apple Podcasts: https://podcasts.apple.com/us/podcast/decouple/id1516526694?uo=4

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• Pocket Casts: https://pca.st/ehbfrn44

• RSS: https://anchor.fm/s/23775178/podcast/rss

Website: https://www.decouple.media

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