Pacific Fusion says it has found a way to simplify and cut the cost of its fusion machine by letting a tiny bit of magnetic field “preheat” the fuel before it is compressed—eliminating the need for an expensive laser system and some auxiliary magnets. The tweak, validated in recent tests at Sandia National Laboratories, could remove one of the thorniest cost hurdles for pulsed inertial confinement fusion.
A Small Step With Big Cost and Complexity Implications
The company’s approach, known as pulser-driven inertial confinement fusion (ICF), uses a massive electrical pulse to generate a magnetic field that rapidly crushes a small fuel capsule—about the size of a pencil eraser—within tens of nanoseconds. Historically, these capsules required a preheat stage, often delivered by lasers and sometimes assisted by magnets, adding 5%–10% to the energy budget and a great deal to capital and maintenance costs.
Pacific Fusion’s insight was to redesign the thin metallic cylinder that surrounds the fuel so a carefully controlled fraction of the magnetic field leaks into the fuel just before the main compression. That gentle preheat, the company says, costs a tiny fraction of the system’s energy—well under 1%—yet achieves the same effect as a dedicated preheating laser.
The target architecture is pragmatic, not exotic: a plastic fuel capsule wrapped in aluminum, with the metal thickness tuned to modulate how much field “seeps” through in the lead-up to the pulse. Manufacturing tolerances are comparable to mature ammunition-grade processes, keeping component costs low and supply chains straightforward.
Why This Matters for Fusion Economics and Cost
Laser preheat systems at the power and reliability levels envisioned for high-gain ICF easily run into nine figures. By removing that subsystem, Pacific Fusion slashes capital cost and complexity, trims downtime, and reduces the number of high-precision components that must be aligned and serviced. Auxiliary magnets used solely for preheat can also be simplified or removed, further easing the engineering burden.
The central question for fusion remains whether the total cost to spark and sustain reactions can undercut the wholesale price of electricity. Even modest reductions in capex and maintenance can move the needle on levelized cost of energy, especially for systems expected to fire repeatedly at a high duty cycle. Cutting out a $100 million-class laser while preserving performance is the kind of step-change the sector needs to look commercially credible.
How It Compares Across Fusion Approaches
Pacific Fusion’s pulsed strategy differs from steady-state magnetic confinement pursued by companies like Commonwealth Fusion Systems, which is constructing a high-field tokamak. Those devices operate continuously and involve different cost drivers, notably superconducting magnets and complex heat handling. Pacific Fusion’s design, by contrast, lives or dies by shot-to-shot economics: target cost, repetition rate, and system uptime.
The broader ICF field has momentum. The National Ignition Facility at Lawrence Livermore National Laboratory demonstrated scientific breakeven with laser-driven shots, showing that fusion plasmas can yield more energy than they absorb from the driver. But translating that feat into a power plant demands lower-cost, higher-repetition systems. Sandia’s Z Pulsed Power Facility—where Pacific Fusion has been testing—specializes in delivering extreme currents and pressures, making it a proving ground for magnetically assisted ICF concepts.
Engineering Details That Unlock Significant Savings
The key is timing and materials. By tailoring the aluminum liner’s thickness and the current waveform, the magnetic field penetrates just enough to warm the fuel before the implosion, improving compression without extra hardware. Because the energy involved is negligible compared with the main pulse, the new method barely changes the power requirements or pulser size. Yet it removes entire subsystems that would otherwise crowd the reactor hall and tax maintenance crews.
Equally important, the experiments tighten the feedback loop between simulations and hardware. Fusion design is awash in models; only careful testing can nail down the real-world behavior of fields, plasmas, and materials under extreme conditions. Sandia shot data helps refine Pacific Fusion’s codes, improving confidence in how the system will scale to higher gains and higher repetition rates.
What to Watch Next as Pacific Fusion Scales Up
The next milestones are familiar: demonstrate reproducible gains with the simplified targets, scale shot frequency, and prove reliable target manufacture and insertion. Progress on these fronts will determine whether the cost advantage survives contact with the grind of power plant operations.
If the approach holds, Pacific Fusion will have shown that a modest materials tweak can remove one of the most expensive elements in an ICF power system. In a field where every component competes with the future price of electrons on the grid, turning preheat from a nine-figure subsystem into a rounding error is meaningful—and potentially market-making.