Zap Energy's sheared-flow stabilized Z-pinch device — demonstrating a fundamentally different approach to magnetic confinement that eliminates the need for expensive superconducting magnets.
FuZE (Fusion Z-pinch Experiment) is the foundational experimental platform developed by Zap Energy, a Seattle-area fusion startup spun out of the University of Washington and Lawrence Livermore National Laboratory. The device demonstrates a sheared-flow stabilized Z-pinch — a confinement approach that uses the plasma's own flowing current to create the magnetic field that confines and compresses it, eliminating the need for large external magnets entirely.[1]
In a Z-pinch, a strong electrical current flows axially through a plasma column. The resulting azimuthal magnetic field pinches the plasma radially inward, compressing and heating it to fusion-relevant conditions. Classical Z-pinches are notoriously unstable, with sausage and kink instabilities disrupting the plasma in microseconds. Zap Energy's breakthrough is the use of sheared axial flow — a velocity gradient along the plasma column that suppresses these instabilities, allowing the pinch to persist long enough for meaningful fusion reactions.[2]
FuZE and its successor devices at Zap Energy have demonstrated thermonuclear-regime neutron production, confirming that the sheared-flow stabilization approach can sustain plasma conditions relevant to fusion. The team has published peer-reviewed results showing plasma temperatures in the kiloelectronvolt range and neutron yields consistent with thermonuclear (not beam-target) origin.[2]
Zap Energy's development roadmap involves scaling the Z-pinch to higher currents and longer pulse durations. The company has built successive generations of devices with increasing performance, working toward a prototype that can demonstrate net energy gain. Zap has raised over $200 million in funding from investors including Chevron, Lowercarbon Capital, and Breakthrough Energy Ventures.[3]
The absence of superconducting magnets, vacuum vessels surrounding the plasma, and complex magnetic coil arrays could make a Z-pinch reactor far simpler and less expensive than tokamak or stellarator designs. The linear geometry also lends itself to modular, factory-built components. However, significant physics and engineering challenges remain in scaling the concept to energy-producing conditions and sustained operation.[1]