About Epithermal

A Team That Builds Reactors Others Can't.

Career reactor and space-nuclear engineers who've taken first-of-a-kind designs from paper to full power.

Who We Are

Reactor Engineering, in One Shop

We serve public- and private-sector clients alike. Epithermal Power is based in Los Alamos, New Mexico, and our engineers have spent their careers designing, testing, and bringing to power some of the most demanding micro- and space-reactors ever built.

Why Us

We're Not Reactor Tourists

Micro- and space-reactors are our craft, not a trend

Real reactors : designed, built, and tested, not slideware
Deep, not broad : decades of hands-on micro- and space-reactor work
Been there : when a first-of-a-kind reactor has to work the first time, we've already done it

10+

Reactor Designs in Portfolio

Mission Classes, One Platform

25+

First-of-a-Kind Designs

15+

Active R&D Programs

CRISP

Integrated 4D Platform

Track Record

We've Already Done the Hard Part.

Delivered from concept to full-power test on first-of-a-kind reactors.

Program Record

From Design to Test

Design · Build · Test

Space-Reactor Demonstration Programs

Critical · Zero-Power

Critical Reactor Experiments

Flight-Class

Space Power & Propulsion Designs

Integrated 4D

End-to-End Reactor Multiphysics

Let's Build the Reactors That Power Earth and Space.

Partner with a team that has designed, built, and tested real reactors.

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