Lightning Strikes 12 Times a Minute Inside Zap Energy Fusion Platform

Lightning Strikes 12 Times a Minute Inside Zap Energy Fusion Platform
by Clarence Oxford
Seattle WA (SPX) Oct 01, 2025

Zap Energy has advanced its Century test platform to sustain more than 100 plasma shots at a frequency of 0.2 Hz, equivalent to one discharge every five seconds. Each pulse generated currents up to 500 kiloamps, about 20 times the strength of a natural lightning strike, within a chamber lined by flowing liquid bismuth. During the record operation, Century consumed 57 kilowatts of total input power, with 39 kilowatts delivered directly into the plasma system.

This achievement represents a twentyfold improvement in sustained average power compared with Century's 2024 commissioning run, marking a major advance toward commercial fusion systems that use repetitive pulsed power and liquid metal cooling. Unlike approaches requiring superconducting magnets or lasers, Zap's sheared-flow-stabilized (SFS) Z-pinch compresses and stabilizes plasma using electrical pulses driven through the gas.

"Prolonged operations of a fully integrated, repetitively pulsed system at 30 kilowatts gives us a much clearer picture of what a sheared-flow Z-pinch fusion power plant will actually look like," said Matthew Thompson, VP of Systems Engineering at Zap Energy. "Century's real-world tests of our engineering subsystems mean we've already begun to identify and solve many of the most difficult commercial technology challenges."

Century integrates three core technologies: repetitive pulsed power, liquid metal walls for absorbing and transferring heat, and durable electrodes designed to endure extreme operating environments. Since operations began last year, Zap has upgraded each subsystem, including a 2,500-pound liquid bismuth circulation loop, a centrifugal liquid metal first wall, a 200-kilowatt air-cooled heat exchanger, a redesigned nose cone tipped with liquid metal, and a high-flow cathode cooling system.

"Century is maturing technologies that will ultimately convert energy from our fusion reactions into electricity or industrial heat-systems engineering has historically been overlooked in fusion development," said Benj Conway, Zap Energy CEO and co-founder. "Fusion is not just a plasma problem. It's a systems integration problem."

Each Century shot begins when capacitor banks draw power from the grid, store it, and release it as a short burst into the vacuum chamber. The pulse ionizes hydrogen or helium gas into a hot plasma filament. Because Century's purpose is engineering validation, it does not use fusion-grade fuels and therefore produces no neutrons. Thermal energy from the plasma is absorbed by circulating liquid bismuth, transferred to a heat exchanger, and cycled back into the system.

Since June 2024, Century has scaled from single plasma shots every 10 seconds at ~1.4 kilowatts to a steady one shot every five seconds at ~30 kilowatts. In February 2025, the DOE certified a three-hour campaign with over one thousand consecutive plasma discharges at more than 100 kiloamps each. To date, the system has fired more than 10,000 shots, providing critical insight into repetitive Z-pinch performance.

Fusion Science and Technology recently published details of Century's design and commissioning runs, and Zap Energy will continue to increase repetition rates and power levels in future campaigns.

Research Report:Century: Zap Energy's 100-kW-Scale Repetitive Sheared-Flow-Stabilized Z-Pinch System with Liquid Metal Cooling