Lawrence Livermore-Pacific Fusion Collaboration Breaks New Record to Advance America’s High-Gain Fusion Capability

LLNL pulsed-power prototype surpasses 3,000 shots through collaboration with Pacific Fusion, demonstrating the maturity of a key U.S. capability and the value of government-industry partnership

FREMONT, Calif.--(BUSINESS WIRE)--Pacific Fusion today announced that a pulsed-power prototype designed and built at Lawrence Livermore National Laboratory has surpassed 3,000 shots under a Cooperative Research and Development Agreement with Pacific Fusion, marking a key milestone in the development of high-gain fusion and a practical example of government-industry partnership at work.

The prototype, called Sirius, is an impedance-matched Marx generator (IMG), which is a new pulsed-power architecture designed to deliver short, powerful electrical pulses efficiently and repeatedly. It is the same core technology Pacific Fusion is now scaling for its own fusion system. The 3,000-shot campaign shows how technology first developed at a national laboratory can be validated through repeated testing and scaled quickly by industry to support national needs.

That matters because the United States urgently needs new sources of affordable, reliable electricity to power surging demand for AI and electrification, as well as new high-yield experimental capabilities for stockpile stewardship. Pacific Fusion is building rapidly to support both, developing a modular pulser platform to produce abundant, affordable energy and advance the high-energy-density science essential to national security.

“This is a concrete example of what government-industry collaboration can deliver when both sides are committed,” said Keith LeChien, Co-founder and Chief Technology Officer of Pacific Fusion. “We are taking innovation from the lab and moving quickly to build and scale systems that serve America’s needs. The result is a credible shot at high-yield, high-gain fusion this decade — and a path to turning U.S. scientific leadership into a critical capability that will keep the U.S. ahead of China.”

Pulsed power works by taking electricity from the wall plug, storing it briefly, and releasing it in an enormous burst — like a lightning bolt — in about 100 nanoseconds. For fusion energy, that burst can create the extreme conditions needed to compress fuel and release energy. The same pulser technology can also create extreme states of matter for high-energy-density science experiments, with applications ranging from materials testing, radioisotope production and national security.

The IMG was co-invented by LeChien and LLNL researcher Bill Stygar as a more direct way to deliver a fast, efficient electrical pulse. Conventional pulsed-power machines, called Marx generators, stack voltages. By contrast, the IMG stacks waves using a pulser by charging capacitors in parallel and then discharging them in a single step, through carefully timed stages on a common transmission line. The pulse is then transmitted directly to the target. In the Sirius campaign, each pulse of the four-stage prototype delivered 60 gigawatts to a resistive load in a 100-nanosecond pulse, with 95% energy efficiency.

Researchers at LLNL say the appeal of the IMG approach is its relative simplicity. “Conventional pulsed-power machines often require several stages of pulse compression, which can add complexity, maintenance demands and safety considerations,” said Kumar Raman, LLNL project manager in a LLNL blog.

The 3,000-shot campaign supported through the Pacific Fusion CRADA focused on component lifetime and reliability – real experimental data that’s proven invaluable to understanding how components behave over many repeated shots.

It’s data that Pacific Fusion has used to design, build and scale its own pulsed-power technology at extraordinary speed. In June, the company announced the completion and validation of a pulsed-power prototype that expanded the Sirius platform by roughly 11x – delivering ~440 GW of peak output power and ~1.1 MV peak voltage in 80 nanoseconds – the highest-power, single-step pulsed-power driver ever demonstrated. Pacific Fusion is now working to demonstrate a system that’s roughly 40x the size of Sirius.

Pacific Fusion has raised more than $1 billion in private capital and is working to achieve net facility gain by 2030. Later this summer, Pacific Fusion will break ground on the world’s largest high-gain, high-yield facility called the Demonstration System in Albuquerque, New Mexico. The system is designed to produce fusion bursts exceeding 100 megajoules – or more energy output than the total stored energy used to drive the reaction, making it the first and only net facility gain fusion facility in the world.

“China is moving aggressively to build the next generation of fusion infrastructure, pouring billions into new facilities,” LeChien said. “The U.S. invented many of the breakthroughs that made this moment possible here and abroad, but to win we have to build. The government needs a significant coordinated investment in energy and national security fusion infrastructure, and months matter. The stakes could not be higher.”

About Pacific Fusion

Pacific Fusion was founded in 2023 to deliver affordable fusion energy to power cities, businesses and homes. The company is developing a pulser-driven inertial fusion system designed to achieve net facility gain, meaning more fusion energy output than stored energy input, by 2030. Pacific Fusion is headquartered in the San Francisco Bay Area with operations in New Mexico. For more information, visit pacificfusion.com.