Not Your Typical Tokamak The National Spherical Torus Experiment-Upgrade (NSTX-U) is the largest spherical tokamak in the U.S. and designed to be the most powerful in the world. Its compact design makes it an ideal candidate to serve as the model for a fusion pilot plant followed by a commercial fusion reactor. Objective NSTX-U is a spherical tokamak, a fusion device shaped more like a cored apple than the doughnut-like shape of conventional tokamaks. It can produce high-pressure plasmas — essential ingredients for fusion reactions — with less energy at lower costs. Its sophisticated features enable scientists to test the viability of this compact design to reliably generate cost-effective electricity from fusion energy. Pause video ■ “The National Spherical Torus Experiment-Upgrade (NSTX‑U) will help to determine whether the spherical tokamak design can scale to commercial reactor level.” – Steve Cowley, Laboratory Director A Worldwide User Facility Scientists from across the globe use NSTX-U to test, experiment and better understand how best to control hot and unpredictable plasma in near-steady conditions to produce energy.NSTX-U Research Users & Collaborators Key Features Feel the PowerNew and strong central magnets produce the highest magnetic field strength of any large spherical torus, allowing for near steady-state conditions. Feel the HeatFlexible heating systems create and heat the plasma to 100 million degrees using beams of high-energy neutral particles and high-power radio waves. Feel the ImpactEach “shot” on NSTX-U provides a tremendous amount of information, and our state-of-the-art diagnostics can accurately measure the properties of plasma. Feel the FutureThe system is built to eventually investigate the use of liquid lithium in protecting the device’s walls from extreme heat. NSTX-U Leadership Stanley Kaye Director, NSTX-U Research Program Jack Berkery Deputy Director, NSTX-U Research Program Rajesh Maingi Head of Tokamak Experimental Science Dave Micheletti Deputy Associate Laboratory Director for Engineering Stefan Gerhardt Senior Managing Research Physicist Masayuki Ono Principal Research Physicist Recovery Project A failed coil led to a full-scale investigation of the NSTX-U's hundreds of intricate parts. NSTX-U Recovery Project engineers have replaced many of the essential components of the device to make it more powerful, efficient and precise. Each component is designed, analyzed and built to exact specifications under the guidance of PPPL engineers and technicians and tested before being installed in the device. Today, the NSTX-U Recovery Project is 88% complete. Progress Timeline Track updates on the NSTX-U. Timeline Virtual Tour Related Links NSTX-U Publications Related Documents National Spherical Torus Experiment-Upgrade (NSTX-U) Recent News Baking the perfect pie one piece at a time: PPPL makes progress on central magnet of NSTX‑U Oct. 25, 2024 Conductors for magnet at the heart of PPPL’s NSTX-U arrive in Spain June 26, 2024 NSTX-U is poised to close the gaps between today’s research tokamaks and tomorrow’s commercial utilities Jan. 3, 2024 The world travels of the components at the center of the National Spherical Torus Experiment-Upgrade Oct. 20, 2023