Zap Energy Hits 100 Experiments in New Approach to Fusion Power

Zap Energy, a Washington-based fusion startup, has successfully run more than 100 plasma experiments using a design called the sheared-flow-stabilized Z-pinch, marking an important operational milestone in its development. The work has been carried out at the company's facility, where researchers have been testing and refining this particular approach to creating fusion reactions.

How the Z-Pinch Works

Most mainstream fusion research focuses on a design called the tokamak, which uses large external magnets to hold hot plasma in place. Zap Energy is pursuing something different: the Z-pinch. In this configuration, the electric current running through the plasma itself creates the magnetic field needed to contain it—no bulky external magnets required. The catch is that plasma can become unstable under these conditions. Zap Energy addresses this by using what's called "sheared-flow stabilization," which means creating controlled differences in plasma velocity that suppress the instabilities that have historically derailed earlier Z-pinch attempts.

The entire process happens remarkably fast—in less than one millisecond, inside a cylindrical vacuum chamber about 10 feet long. That speed places intense demands on timing and measurement systems. Zap Energy operates two experimental devices: the Fusion Z-pinch Experiment (FuZE) and a more advanced version called FuZE-Q. Both feed into the company's ongoing research to optimize plasma conditions.

Where This Technology Came From

The sheared-flow Z-pinch idea grew out of fundamental research conducted by Uri Shumlak's laboratory at the University of Washington over roughly two decades. Shumlak's team developed the theory that plasma flows moving at different speeds in different regions could stabilize the Z-pinch configuration. This is quite different from how tokamaks and stellarators work: rather than relying on intricate external magnetic geometries, the Z-pinch approach uses the plasma's own current-generated magnetic field.

I have watched magnetic confinement fusion evolve since the early days of stellarator research in the 1960s, and each generation of scientists has had to invent new ways to control plasma instabilities—usually through more sophisticated control systems and better computational modeling. What is happening now with Z-pinch is a return to simpler underlying physics, but leveraging modern computing power and control that earlier researchers simply did not have.

Why 100 Shots Matters

For fusion researchers, the ability to produce 100 consistent, repeatable plasma shots is no small thing. Each shot yields data on plasma temperature, density, how long the plasma stays confined, and what instabilities occur. That consistency is essential for systematic study and optimization. You learn more when you can run the same experiment over and over and compare results.

One practical advantage of Z-pinch systems is speed of repetition. Unlike some longer-pulse fusion devices that need extended cooling periods between shots, Z-pinch systems can fire in rapid succession. That could help researchers iterate faster during development and, eventually, could make commercial systems more efficient at actually producing power.

The Bigger Picture

Benj Conway, CEO and co-founder, has led Zap Energy since May 2017, guiding the company through multiple funding rounds and technical milestones. Zap Energy is far from alone. The private fusion sector has grown substantially in recent years, with companies like Commonwealth Fusion Systems, TAE Technologies, and Helion Energy all pursuing alternative approaches to the tokamaks that dominate government-funded fusion programs. Meanwhile, ITER—the world's largest tokamak project—continues its own development.

The real story here is about diversification. Instead of betting everything on one design, the fusion ecosystem is exploring whether alternative confinement approaches might reach practical power generation faster. Z-pinch systems do offer some engineering simplicity—no need for the massive external coil systems that tokamaks require. But simplicity on paper does not guarantee success in practice. Any fusion approach, including Z-pinch, must ultimately achieve what physicists call the "triple product": reaching high enough temperature, high enough density, and holding the plasma long enough to generate more energy than it consumes. That remains an exceptionally difficult problem.

What Comes Next

This 100-shot milestone sets up the next phase of work: parameter optimization and scaling studies. Researchers will likely focus on extending how long the plasma stays confined, pushing temperatures and densities higher, and ensuring reliable performance shot after shot.

The journey from experimental success in the lab to a commercial fusion power plant is a very long one. Beyond plasma physics, Zap Energy will need to develop systems for handling tritium (the hydrogen isotope used in fusion fuel), extracting the heat produced, and converting that heat to electricity. And the approach must ultimately prove it can produce net energy gain and operate at the scale needed to make commercial power.

The fusion industry continues to pursue multiple technical pathways at once, which reflects an honest recognition that the first company or project to achieve practical fusion power generation may be using an approach that today seems unconventional. Zap Energy's progress with Z-pinch adds one more piece of evidence to the broader picture: fusion is being pursued from many different angles simultaneously, and we will not know which path succeeds until one of them actually does.