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Energy Secretary Moniz Launches the Nation’s Newest Fusion Experiment at PPPL

National Spherical Torus Experiment – Upgrade will help determine the course of fusion energy for years to come

U.S. Department of Energy Secretary Ernest Moniz dedicated the most powerful spherical torus fusion facility in the world on Friday, May 20, 2016. The $94-million upgrade to the National Spherical Torus Experiment (NSTX-U), funded by the DOE Office of Science, is a spherical tokamak fusion device that explores the creation of high-performance plasmas at 100-million degree temperatures many times hotter than the core of the sun.

NSTX-U at the Princeton Plasma Physics Laboratory (PPPL) will allow researchers around the world to explore how to create fusion reactions – essentially creating a star on Earth – with the goal of bringing clean, reliable, safe, and virtually unlimited energy to the world. The promise of fusion eliminates the need to burn fossil fuels, accumulate greenhouse gases in the atmosphere, warm the Earth, and worry about nuclear waste – instead, providing clean energy that uses ordinary seawater as a fuel.

“The vastly expanded capabilities of this spherical tokamak will enable us to explore new physics regimes and tackle the major engineering problems for fusion energy,” Moniz said.

NSTX-U draws on a 65-year-old legacy of fusion energy research at Princeton University’s Plasma Physics Laboratory, where in the 1950s physicist Lyman Spitzer created a machine he called a stellarator to produce energy the same way as the sun – through fusion reactions where light elements collide and fuse together, releasing enormous amounts of energy. Experimental stellarators and tokamaks, the two most prominent fusion reactor designs, now dot the globe.

“This is exciting new territory, and we’re thrilled to embark on the next frontier of fusion research. This device could transform the world by showing us the way to a pilot plant design for the generation of power from fusion energy for use by all,” said Stewart Prager, director, Princeton Plasma Physics Laboratory.

Moniz toured the new device, which took almost four years to build. The upgraded machine doubles the heating power, magnetic field strength and plasma current relative to its predecessor, and increases the duration of fusion experiments – or “shots” – to up to five seconds. It thus becomes the most powerful such facility in the world.

Moniz unveiled a plaque dedicated to the workers who have made NSTX-U a reality and will keep it running for at least the next decade. The plaque is mounted in the NSTX-U Control Room where physicists, engineers, and technologists control the pulses of plasma that create fusion reactions.  

Also attending the ceremony were U.S. Sen. Cory Booker (D-NJ), U.S. Rep. Bonnie Watson Coleman (D-12), and Princeton University President Christopher Eisgruber.  “This upgrade means that fusion remains a priority in the nation’s energy portfolio,” Eisgruber said. “NSTX-U keeps the United States and Princeton at the forefront of fusion science, poised to seize exciting opportunities to create a clean, safe, and prosperous future.”

Sen. Booker also commented on the upgrade. "Fusion power has the potential to be a safe, clean, and sustainable energy source that could provide the United States with a nearly limitless energy supply,” Booker said.  “That’s why I remain committed to supporting innovation in this critical technology so institutions like Princeton can ensure our nation remains a leader in developing fusion power.  I applaud Secretary Moniz for recognizing the great work we are undertaking right here in New Jersey.”

Spherical tokamaks are compact fusion facilities shaped like cored apples, compared with the doughnut-like shape of conventional tokamaks that are in wider use. The compact shape enables spherical tokamaks to confine highly pressurized plasma within lower magnetic fields than conventional tokamaks, potentially making them more cost-effective.

As a nationwide, and worldwide, experiment, NSTX-U is a collaboration of researchers representing almost 60 institutions from across the United States, England, Europe, Asia, Russia, and Central America.

The Princeton Plasma Physics Laboratory, on Princeton University’s Forrestal Campus in Plainsboro, N.J., is devoted to creating new knowledge about the physics of plasmas — ultra-hot, charged gases — and to developing practical solutions for the creation of fusion energy. Results of PPPL research have ranged from a portable nuclear materials detector for anti-terrorist use to universally employed computer codes for analyzing and predicting the outcome of fusion experiments. The Laboratory is managed by the University for the U.S. Department of Energy’s Office of Science, which is the largest single supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

U.S. Department of Energy
Princeton Plasma Physics Laboratory is a U.S. Department of Energy national laboratory managed by Princeton University.

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