Energy · Fusion & National Security
A warehouse in the New Mexico desert. A billion dollars of capital. And a neighbor most companies would never choose: a US nuclear-weapons lab.
Pacific Fusion isn't hiding that partnership. It's building around it.
Pacific Fusion is assembling a pulsed-power fusion machine in Los Lunas, New Mexico, aiming to hit "net facility gain" — generating more energy than the entire facility consumes — by the end of the decade. The site sits down the road from Sandia National Laboratories, and the two are cooperating on technology that serves both civilian and the maintenance of America's aging nuclear-weapons stockpile. It's a rare, explicit case of a private energy start-up and a national-security lab sharing the same physics problem.
Beneath a wall-sized American flag, workers and industrial robots piece together the first of more than 150 truck-sized Marx generator modules.
A Billion-Dollar Bet Built Next Door to a Weapons Lab
Most energy start-ups pick their real estate for cheap land or friendly permitting.
Pacific Fusion picked Los Lunas, New Mexico, for a very different reason: proximity to Sandia National Laboratories, a facility built for national-security research.
That's not an accident of geography. It's the entire strategy.
Founded in 2023, Pacific Fusion has already raised more than a billion dollars, contingent on hitting specific technical milestones along the way.
That's serious money, but it's part of a much bigger wave. Dozens of fusion start-ups have collectively raised over $14 billion in the past five years.
Physicist Keith LeChien, the company's chief technology officer and co-founder, doesn't undersell the ambition.
He calls the project "transformative for both fusion energy and defence applications."
Inside the Los Lunas warehouse, the scale of the undertaking is already visible.
Workers and industrial robots are assembling the first of more than 150 truck-sized modules, each one a cylindrical bank of capacitors.
When complete, these modules will ring a central reaction chamber like the legs of a giant metal crab — an image striking enough that it's hard to shake once you've pictured it.
The goal for all of them, working in concert, is startlingly precise: hit a pea-sized fuel capsule with a pulse thousands of times stronger than a lightning bolt.
How Pulsed Power Actually Triggers Fusion
Fusion sounds abstract until you break down what actually has to happen inside that reaction chamber.
The 150-plus modules are called impedance-matched Marx generators — cylindrical capacitor banks designed to fire in perfect unison.
When they discharge together, they generate an electrical pulse of extraordinary intensity, aimed directly at a tiny capsule of at the machine's center.
That enormous current generates a powerful magnetic field around the fuel capsule, and that field does the actual work: it compresses the capsule violently.
Under enough heat and pressure, the nuclei of hydrogen isotopes inside the capsule melt together, forming helium and releasing energy in the process.
That's fusion in its most literal sense — the same reaction that powers the sun, compressed into a machine you could walk around inside a New Mexico warehouse.
The company is ramping up production of these modules rapidly, racing toward a specific benchmark: net facility gain.
That's the point where the machine produces more energy than the entire facility consumes to run it — not just the reaction itself, but everything around it.
Several fusion researchers outside the company describe the pulsed-power approach as genuinely promising.
But fusion engineer Michael Campbell, of the University of California, San Diego, offers a useful dose of realism: "There's still a long way to go."
Lasers vs Lightning: Why NIF's Playbook Isn't Being Copied
To understand why Pacific Fusion chose electricity over lasers, you have to start with what came before.
In 2022, the US National Ignition Facility in Livermore, California, made history — 192 lasers aimed at a single hydrogen pellet achieved "ignition" for the first time.
That meant the fusion reaction released more energy than what actually hit the target. A real milestone.
But NIF never achieved net facility gain, because the reaction's output was still far smaller than the energy the entire facility consumed to fire those lasers.
Here's the number that explains everything: at NIF, less than 1% of the energy used to fire the lasers actually reaches the fuel capsule.
The rest is lost converting electrical charge into light, then X-rays, then kinetic energy — with losses compounding at every single stage.
Pulsed power skips most of that conversion chain entirely. LeChien says it's simply more energy efficient than lasers, by design.
In Pacific Fusion's system, around 12% of the initial charge is expected to reach the target — roughly twelve times better than NIF's laser route.
LeChien expects the demonstration facility to use about 80 megajoules of electrical energy per pulse, aiming for roughly 100 megajoules of fusion energy back.
That would be a genuine net facility gain — not just ignition, but the harder, more meaningful benchmark.
Plasma physicist Kyle Peterson, of Sandia, frames the broader landscape well: "the answer isn't obvious" — which is exactly why so many competing approaches exist at once.
The Nuclear Weapons Connection Nobody's Hiding
Here's the part of this story that makes it more than just another energy start-up profile.
Sandia National Laboratories focuses on national-security research — and it's working cooperatively with Pacific Fusion, not from a distance.
The stated goal of that cooperation: optimizing pulsed-power fusion for both energy generation and weapons applications, together.
That's a striking admission for a private company to make openly, and it isn't buried in the fine print.
The logic behind it is straightforward once you think about what a fusion machine actually simulates.
Compressing hydrogen isotopes under extreme pressure and heat, at speed, is directly relevant to studying America's aging stockpile of nuclear warheads.
Without live nuclear testing, facilities like this become one of the only ways to study weapons physics experimentally at all.
That's precisely why LeChien describes the project as transformative for defence applications, not just clean energy.
It also explains the funding logic. A technology with both civilian and national-security value has two very different reasons to attract serious capital.
Whether that dual purpose accelerates the science, or complicates it, is a genuinely open question worth watching as the facility comes online.
From Ignition to Net Facility Gain — The Real Scoreboard
It's worth being precise about what would actually count as success here, because the goalposts in fusion research keep shifting.
| Milestone | Facility | Status |
|---|---|---|
| Ignition (reaction output > energy hitting target) | NIF, 2022 | Achieved |
| Net facility gain (output > total facility energy use) | NIF | Not achieved |
| Net facility gain, target | Pacific Fusion | Aiming for end of decade |
| Continuous, power-plant-scale operation | Any fusion approach | Not yet solved |
Campbell puts the significance of net facility gain simply: "it would be a very good achievement."
He frames the underlying logic even more bluntly — if you ever want to produce electricity from this, every shot has to yield more than it takes from the grid.
That's the bar Pacific Fusion is aiming at directly, with its projected 80-megajoule input and 100-megajoule output per pulse.
But even LeChien is candid about how far that still is from an actual power plant.
The initial energy gain from each pulse would be roughly one-fifth of what's needed to operate a real power plant.
Closing that gap will require further basic physics research, not just engineering refinement.
On top of that, running the facility continuously — rather than in isolated pulses — brings its own separate set of substantial engineering challenges.
Net facility gain, in other words, would be a genuine milestone. It would not be a finished power plant.
Manohar Insight
What stands out to me most isn't the physics — it's the candor.
A private company openly stating that its energy machine also serves nuclear-weapons research is a rare kind of transparency in this space.
It would have been easy to soften that framing for public consumption. Pacific Fusion didn't.
There's also something clarifying about Campbell's blunt standard: every shot has to yield more than it takes from the grid, or it's not really progress toward power.
That single sentence cuts through a lot of fusion hype far better than any funding number could.
The $14 billion flowing into this sector over five years tells you investors believe in the destination. It says nothing about how close anyone actually is.
Net facility gain, if Pacific Fusion hits it, won't be the finish line — it'll be the first honest proof the race is winnable at all.
Join the Signal
A fusion company openly cooperating with a nuclear-weapons lab — does that dual purpose speed up the path to clean energy, or does it complicate the mission? Share your take in the comments.
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