HomeCompaniesApollo Atomics, Inc.
Apollo Atomics, Inc.

We make the most compact nuclear reactors

Active Founders
Assil Halimi
Assil Halimi
Founder
Founder at Apollo Atomics, Inc. (YC P26). PhD in Nuclear Engineering from MIT with 15 peer-reviewed publications and 2 patents on reactor design and fuel optimization. Previously reactor operator at Engie (Belgium's nuclear operator) and advanced reactor designer at EDF (world's largest nuclear operator). Worked with Westinghouse, NuScale, Rolls-Royce on PWR development.
Drew Walker
Drew Walker
Co-Founder/COO
Co-Founder & COO of Apollo Atomics (YC P26). He previously co-founded Blue Innovations Group, an electric boat startup, and served in the White House. He holds a B.A. in Political Science from George Washington University.​​​​​​​​​​​​​​​​
Company Launches
Apollo Atomics: The Modern Nuclear Company
See original launch post

Hey everyone 👋

We're Assil and Drew — co-founders of Apollo Atomics.

TL;DR

Apollo Atomics took the pressurized water reactor technology that already powers 80% of the world's nuclear plants and flipped one part, the steam generator, to make the plant an order of magnitude smaller without compromising power. That single change turns a decade-long construction project into a factory-built machine that fits on a truck. We've built a working demonstrator, tested it, and our fuel is already critical before July 4th.

We put the whole story into just over two minutes — it's the clearest version of what we're building we've made so far: ▶️ https://youtu.be/vy8y_t1KAK4?si=FmGF4Q7w6eFkn4No

The Problem

The existing nuclear playbook doesn't work for customers who need power now.

  • Gigawatt-scale nuclear takes 10+ years and ~$20B per plant.
  • Most Small Modular Reactors (SMRs) in development rely on exotic fuels, unproven coolants, or supply chains that don't exist yet.
  • Customers who need power in 2030 are being told to wait until 2035+ and hope.

Data centers, industrials, and utilities have demand today — and no credible nuclear option that can ship on their timeline.

Our Solution

Apollo builds compact pressurized water reactors — the same technology that runs ~80% of the world's nuclear plants today. The difference is that our reactor is roughly 40x more compact, because we shrank only one component: the steam generator.

We keep everything the NRC has already licensed dozens of times — light water, low-enriched uranium, fuel, and components from existing qualified supply chains. The innovation is a single part: the steam generator.

Our Compact Steam Generator (CSG) replaces the massive, hand-built steam generator at the heart of a conventional PWR with a component 20x smaller, delivering the same thermal power — pre-tested, transportable, and contracted at a fixed price. That one change is what takes a reactor from a decade-long construction project to a factory-built machine deployable in less than 24 months.

Our product roadmap is three reactors, each on a truck, each for a different customer segment:

  • A-10 — 10 MWe
  • A-50 — 50 MWe
  • A-300 — 300 MWe

Our Ask

If any of these are you, we'd love to talk:

  • Data center operators and hyperscalers sourcing 24/7 firm power for 2028–2035 deployment.
  • Industrial offtakers (chemicals, refining, heavy manufacturing) needing process heat or behind-the-meter electricity.
  • Utilities evaluating SMRs for grid-connected generation.

👉 Reach us at [email protected] and [email protected].

Apollo Atomics, Inc.
Batch:Spring 2026
Status:
Active
Primary Partner:Tom Blomfield