X-Energy
Amazon Reserved a Nuclear Plant.
None of Them Are Running Yet.
In October 2024, Amazon signed a deal with X-Energy: an option to develop up to 5 gigawatts of nuclear power by 2039. In conventional terms, that is the scale of four or five reactors.
And yet the company building those reactors, X-Energy, has not a single reactor in operation. Not one physical unit yet exists in the world.
Even so, the company holds roughly $1.03 billion in cash. Posting a net loss of about $390 million a year, in 2026 it is selling stock to raise about $694 million more.
What the S-1 presents is a company selling, in the 2026 stock market, a power plant that is not supposed to run until the 2030s.
Ten questions. We lay out only what the S-1 says.
S-1 JOURNAL NEWSLETTER
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- Q1What is this company, really?
- Q2What is it competing on?
- Q3How big is the market?
- Q4Who uses it?
- Q5How does it make money?
- Q6Are the numbers healthy?
- Q7Who runs it?
- Q8Who controls it?
- Q9What does it fear?
- Q10What happens to the money raised?
- —Closing: beyond the ten questions
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Question 1
What is this company, really?
Primary source · from the S-1
Prospectus Summary (p.1+), Business (p.116+) — from the S-1
In one line: a company that designs a nuclear reactor a fraction of the usual size, fueled by uranium sealed in tiny black balls.
A normal nuclear plant is enormous. A single unit runs to the gigawatt class. Building one costs roughly $7–13 billion and takes more than ten years.
What X-Energy builds is 80 megawatts per unit — less than a tenth the size of a normal reactor. Four are deployed together as one set (320 MW). Build small, then line up as many as you need. It is closer to adding battery cells to a phone.
The industry calls it an “SMR” — short for Small Modular Reactor.
X-Energy’s SMR has one more distinctive feature: the fuel is shaped as round balls.
A normal reactor machines uranium into rod-shaped fuel and inserts it into the core. X-Energy does it differently. Inside black balls about six centimeters across (called pebbles), it embeds grains of uranium. These balls are introduced as “the most robust nuclear fuel on Earth” (in the words of the US Department of Energy).
Why a ball? Because “even if an accident happens, it physically cannot melt.”
A normal reactor (a light-water reactor) loses its cooling pumps when the power fails. Lose the coolant, and the core melts. That is the mechanism behind what happened at Fukushima Daiichi.
X-Energy’s reactor is different. As the temperature rises, the nuclear reaction itself decelerates on its own. With no electricity and no water, heat escapes on airflow alone. The black ball wrapping the uranium is, by design, built to stop at a temperature where it does not melt.
Not “stop the accident once it starts,” but
“bind it with the laws of physics so the accident never starts at all.”
Question 2
What does it compete on?
Primary source · from the S-1
Prospectus Summary (Our Competitive Strengths, p.4+), Business (p.116+) — from the S-1
X-Energy competes in three distinctive ways.
It does not build the plants itself
This is the first strange thing. X-Energy sells the reactor design but does not build the reactor itself. It neither owns nor operates them.
It defines its own business this way:
So what does it sell instead?
- Design license fees (“use our reactor blueprint, pay us so much per year”)
- Construction support fees (regulatory filings, engineering, operator training)
- Fuel (supplying those black balls throughout operation)
Rather than building machines in a factory and selling them, it is a business of selling blueprints, operating know-how, and fuel — for 60 years at a stretch.
What does this resemble? It is close to ARM, the company behind the CPUs running inside your phone. ARM does not make CPUs. It sells only the design, and Apple or Qualcomm build the CPU. X-Energy is trying to do the same thing with nuclear reactors.
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Keep reading
- Q3 How big is the market?
- Q4 Who actually uses it?
- Q5 How does it make money?
- Q6 Are the numbers healthy?
- Q7 Who runs it?
- Q8 Who controls it?
- Q9 What is it afraid of?
- Q10 What becomes of the money it raises?
- Closing Beyond the ten questions