Yasir Arafat is the co-founder and CTO of Aalo Atomics, a company developing factory-manufactured modular nuclear power plants designed for AI data centers. Before founding Aalo, Yasir led the MARVEL microreactor program at Idaho National Laboratory.

In this episode of Inevitable, Yasir explains how Aalo became one of four U.S. nuclear startups to achieve criticality by the July 4, 2026 deadline. He breaks down what criticality means, why the milestone matters, and how the team went from a small startup to sustaining a nuclear fission chain reaction in less than a year.

The conversation explores why Yasir believes nuclear's biggest challenges are speed and economics rather than safety or reliability, and how Aalo is trying to address both through factory-based manufacturing. Yasir also shares how the company built its own reactor building in 36 days, tested its full-scale reactor systems, developed scalable fuel assembly manufacturing, and partnered with Idaho National Laboratory to learn how to operate a real reactor.

Finally, Yasir outlines Aalo's path from its zero-power Critical Test Reactor to Aalo-X, a full-powered reactor designed to generate electricity and power a co-located AI data center, and ultimately to the company's commercial Aalo Pod. The discussion also covers DOE demonstration pathways, future NRC licensing, the resurgence of nuclear innovation, and why Yasir believes multiple reactor technologies and companies will be needed to scale nuclear energy.

Note: Aalo Atomics is an MCJ portfolio company.

Episode recorded on August 6, 2026 (Published on August 18, 2026).

In this episode, we cover:

(0:00) An overview of Aalo Atomics
(2:00) What criticality means in a nuclear reactor
(3:38) Why the July 4 deadline was set and why it mattered
(7:07) The final 24 hours before Aalo reached criticality
(9:24) How accurately Aalo's reactor matched its physics models
(11:43) From the MARVEL microreactor to founding Aalo Atomics
(13:56) Why Aalo is focused on nuclear speed and economics
(17:05) Why Aalo built a zero-power critical test reactor first
(19:01) Building a nuclear reactor building in 36 days
(19:21) What Aalo tested beyond the reactor itself
(20:53) Building fuel assemblies for the next 100 reactors
(23:43) Why organizational readiness matters as much as reactor technology
(24:05) Running the CTR and Aalo-X projects in parallel
(24:56) Excavating through unexpectedly difficult basalt rock
(26:03) The progression from CTR to Aalo-X to the Aalo Pod
(29:29) Partnering with turbine suppliers and Crusoe
(31:27) The timeline for powering a co-located AI data center
(32:09) How DOE authorization supports first-of-a-kind reactor demonstrations
(34:01) Moving from DOE demonstrations toward NRC commercial licensing
(42:03) Why Aalo is betting on the next generation of sodium-cooled reactors

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*Editing and post-production work for this episode was provided by The Podcast Consultant

Aalo Atomics on Beating the Odds to Reach Criticality

Inevitable

Aalo Atomics on Beating the Odds to Reach Criticality