Sander Miller

Nuclear Engineer @ Valar Atomics

[Isaiah Taylor - making nuclear reactors @isaiah_p_taylor]

Announcing Valar Atomics' $1B series B led by Sequoia, with Valor Equity Partners, Atreides, Point72, Conviction, and others.

Alongside the $1B equity, we have closed a $200m credit facility led by Erebor and JPM.

I'm excited to welcome Shaun Maguire from Sequoia to our board.

[Schultz @RainingSchultz]

America is cool because whenever we take the wrong tech tree, a college dropout spawns to call you dumb and build the inevitable.

[Isaiah Taylor - making nuclear reactors @isaiah_p_taylor]

I want to clarify something because I’ve gotten a few questions. Ward 250 is a 100kWt reactor. It is licensed to operate at 100kW thermal power, and peak to 250kW thermal power for up to one day.

It is possible that in the future, we will submit a change to our safety basis and push more power out of it—probably a couple MW is easily achievable. The reactor itself is SIZED to 15MW thermal—meaning, the core region is 5m^3, and HTGRs traditionally run at around 3MW/m^3. 5 x 3 = 15. Some HTGRs have run even higher, and there are ideas of how to achieve 6MW/m^3, which would imply 30MW.

However, it would be extremely disingenuous of me to talk about this as a 15MW (or 30MW) reactor. It is not. It is a 100kWt reactor. As I am typing this it is currently making 100kWt. Future reactors we’ll make with the same core size but larger cooling systems will make tens of MW, but this one does not.

I feel that I should say this because others in the field like to refer to critical assemblies, which as critical assemblies are actually not going to make any power at all, by the theoretical power number that should be achievable by a core of that size. If Valar were to play that game, we would talk about Ward 250 as a 15MW or 30MW reactor.

However, Valar does not play that game. You will notice that we did not refer to our Nova Core as a reactor and did not talk about theoretical power output. If you analyze all of our media, we were very careful to never refer to Nova as a reactor or try to characterize power. Why? Because it is a critical assembly built for zero power criticality.

In 2018, NASA built a small reactor named KRUSTY on the same machine that we took the Nova core critical on, LANL’s Comet. This was a small Be-moderated reactor with sodium heat pipes and a series of 125W Stirling engines adding to ~1kWe. That is a 1kWe reactor. Nova was built on the exact same machine, and contained a larger volume of fuel. But we did not say anything about theoretical power output or call it a “1kW reactor” or some nonsense. Because despite the Nova core containing coolant channels, there there was no cooling system attached to it.

Ward 250 is a 100kWt reactor… because it makes 100kWt. It is making 100kWt right now.

[Sander Miller @SanderJMiller]

I think we just turned on the first advanced power reactor in the us

[Isaiah Taylor - making nuclear reactors @isaiah_p_taylor]

Good morning.

Last night at 8:51pm Mountain Time, the Valar Atomics Nuclear Operations team brought Ward 250 to 10kW thermal output. We held this power level throughout the night.

This is another historic milestone from the Valar team, marking first nuclear power by a startup.

[Isaiah Taylor - making nuclear reactors @isaiah_p_taylor]

Good morning.

Last night at 8:51pm Mountain Time, the Valar Atomics Nuclear Operations team brought Ward 250 to 10kW thermal output. We held this power level throughout the night.

This is another historic milestone from the Valar team, marking first nuclear power by a startup.

[White House OSTP 47 @WHOSTP47]

Another historic milestone for @POTUS's Nuclear Reactor Pilot Program. This marks the first @ENERGY reactor to reach criticality outside of a national lab.

Congratulations @valaratomics 🇺🇸

[Isaiah Taylor - making nuclear reactors @isaiah_p_taylor]

Moments ago, Valar Atomics took Ward 250 critical for the first time. This fulfills President Trump’s EO 14301, which called for 3 advanced reactors to go critical by July 4th.

This is our second criticality as a company, and an important step toward our goal of power by July 4.

[Valar Atomics @valaratomics]

Today, the DOE accepted our Documented Safety Analysis (DSA) for the Ward250 Reactor.

The DSA is our final design approval, demonstrating that we have satisfied the DOE’s rigorous safety standards in engineering and construction.

Next, Readiness Review and power before July 4.

[Isaiah Taylor - making nuclear reactors @isaiah_p_taylor]

You Will Be Unleashed

[Isaiah Taylor - making nuclear reactors @isaiah_p_taylor]

Valar Atomics is on track to make power before July 4th in our Ward250 reactor. But before we do that, I asked the team to look back at Project Nova and reflect on what we learned.

We also got some footage of Nova declassified and are sharing it here for the first time. Enjoy!

[Valar Atomics @valaratomics]

Introducing the Modular Citadel production line, capable of producing over 1,000 shielding blocks per year.

The Modular Citadel is a pre-cast, self-tensioning shielding system built for mass-manufactured scale.

Block production is on track for July 4th!

[Isaiah Taylor - making nuclear reactors @isaiah_p_taylor]

Last night, I had the honor of being the keynote speaker at the National Criticality Safety Program's Technical Program Review, where I shared an update on the incredible work that Valar team and NCERC did on Project Nova. So grateful for the critically important work of NCSP.

[Isaiah Taylor - making nuclear reactors @isaiah_p_taylor]

🚨 ATTENTION SPECTRAL ANALYSIS APPRECIATORS 🚨

I need to run a small sample through glow discharge or ICP spectrometer in next 24-48 hours. Sample is in Hawthorne, but I’ll come to you.

Will pay to expedite.

Thank you!

[Isaiah Taylor - making nuclear reactors @isaiah_p_taylor]

Today, Valar Atomics became the first startup in history to split the atom.

Announcing Project Nova, a series of zero power critical tests on Valar Atomics' Nova Core in collaboration with Los Alamos NCERC and NNSS.

Nova went critical for the first time this morning at 11:45am.