Upgrades in place, San Diego’s nuclear fusion facility is back up and running – San Diego Union-Tribune

The DIII-D National Fusion Facility, located on the San Diego campus of General Atomics, is back up and running after completing a series of enhancements in recent months.

The improvements are one small step in a much larger effort by researchers, scientists and engineers working on projects around the world to achieve the elusive goal of someday building nuclear fusion power plants capable of generating an almost limitless amount of clean electricity to energy consumers.

“The upgrades made to DIII-D over the last eight months provide us with exciting new capabilities and key enhancements to existing systems for studying fusion energy,” said DIII-D Director Richard Buttery. “We started this project with a prediction that it would be good … but we actually have evidence that things may be even better than our predictions.”

General Atomics operates the facility on behalf of the U.S. Department of Energy Office of Science. Pronounced “dee-three-dee,” DIII-D acts as a user-facility and laboratory where more than 700 researchers from more than 100 institutions explore nuclear fusion technology.

At the heart of DIII-D is a doughnut-shaped vacuum chamber called a tokamak that is surrounded by extremely powerful electromagnets. Within the tokamak, the magnets confine plasmas — a state of matter with large quantities of ionized particles — at 10 times the temperature of the sun.

That incredible amount of heat allows hydrogen isotopes to fuse together and release energy. In essence, fusion scientists are creating a star on Earth.

“Our goal is to get things very hot but what keeps this very safe is that we deal with very tiny amounts,” Buttery said. “So although it’s super hot, the amount of gas in there is quite small. So even if all of the heat from the plasma comes out, it just erodes a little bit of a tile or something … It’s quite benign and safe in that sense.”

DIII-D is the largest magnetic fusion device in the United States.

After going offline in July 2023, the facility restarted experiments earlier this month.

The upgrades include a new configuration called a Shape and Volume Rise divertor that is designed to remove impurities from the plasma, allowing researchers to better control the plasma’s density and improve fusion performance.

Another enhancement is a system known as Charge Exchange Recombination Spectroscopy that is used to measure the plasma’s behavior inside the tokamak by improving the resolution.

“That measurement system will tell us things about the temperature of the plasma — how hot it’s getting,” Buttery said. “It will also tell us how fast the plasma is spinning.”

Nuclear fusion differs from nuclear fission, which is the process used in nuclear power plants such as the now-shuttered San Onofre Nuclear Generating Station. Fission splits the nuclei of atoms to create power while fusion causes hydrogen nuclei to collide and fuse into helium atoms that release incredible amounts of energy — essentially replicating the power of the sun.

In theory, fusion applied at a commercial power plant could generate vast amounts of carbon-free electricity without producing long-lived nuclear waste or running the risk of a meltdown.

“The end goal is a fusion device that will make heat and, just like a coal power plant does, that heat will run a steam turbine that will produce electricity for us,” said General Atomics scientist Colin Chrystal during a recent tour of DIII-D. “That’s what we’re hoping to do.”

Since the 1950s, scientists and researchers have been lured by fusion’s vast potential, but progress has been painstaking and slow.

No commercial fusion facilities exist. In fact, fusion has generated power for just few seconds and that’s only been done in laboratory settings. A longstanding joke in the energy industry says fusion is always 30 years away.

But with calls for the energy sector to transition from fossil-fuel sources, combined with expected increases in energy demand, nuclear fusion has received more attention.

Investors, including billionaires such as Bill Gates and Jeff Bezos, have poured money into more than 30 fusion startups in the private sector. At a major energy conference in Houston earlier this year, Gates said, “In the long run fusion will be, almost certainly, the primary source of electricity on the planet.”

Recent advances in fusion technology have garnered headlines.

In July 2023, scientists at the Lawrence Livermore National Lab in Northern California were able to repeat an experiment with high-intensity lasers in which a greater amount of fusion energy came out than was put in — at least for a fraction of a second. The experiment used high-intensity lasers, not the magnet technology employed at DIII-D.

Fusion has its share of critics, though.

Some say the technological obstacles are simply too difficult to climb, since the fusion reaction would have to be sustained and repeatable to work on a practical, commercial scale.

Others say spending time and money on fusion research diverts resources from more conventional carbon-free energy sources such as solar, geothermal and wind.

“The climate crisis has to be addressed imminently — really, within the next 10 to 15 years — and a technology that’s still going to take many decades of development is not going to play a role in that initial transition,” Edwin Lyman, a physicist and director of nuclear power safety with the Union of Concerned Scientists, told Yahoo News in December 2022.

Some 35 nations, including the U.S., are collaborating on the ITER project (pronounced “eater”), which is under construction in southern France. ITER is not a power plant but an ambitious research project that looks to pave the way for the development of facilities that could use fusion to generate electricity.

Originally scheduled to cost about $5 billion and begin testing in 2020, ITER’s budget has zoomed to $22 billion, with specific dates for trials put on hold. In November 2022, officials announced that defects had been found in two components of ITER’s tokamak.

The problems led Charles Seife, who authored a book on the history of fusion, to question the viability of the project. In a June 2023 article in Scientific American, Seife said ITER “is on the verge of a record-setting disaster as accumulated schedule slips and budget overruns threaten to make it the most delayed — and most cost-inflated — science project in history.”

General Atomics is playing a vital role at ITER, fabricating and shipping modules that make up the world’s most powerful magnet — called a Central Solenoid — that will be inserted into the heart of the ITER facility.

Weighing 250,000 pounds, each module is hauled from the 60,000 square-foot warehouse at the General Atomics Magnetic Technologies Center in Poway by specially built transport trucks to the Houston Ship Channel and then taken by ship to France. Six of the modules will go into the Central Solenoid and a seventh will be used as a spare.

Thus far, four modules have been successfully sent to ITER. The remaining three are expected to ship out by early next year.

In addition, research and development at DIII-D can help support experiments at ITER.

Despite ITER’s issues and the hurdles that commercial fusion in general face, Buttery is optimistic. In fact, he said that with an aggressive program and sufficient funding, a fusion power plant can be in existence in the 2030s.

“Limitless energy will reduce political tensions,” Buttery said. “It will allow us to solve many of the problems that we have in the world with poverty, where a country is poor and needing resources. … So it really is part of the solution to making, I suppose, a more equitable society but also reducing tensions and bringing up living standards.”

The nuclear clock is ticking.

Originally Published: May 24, 2024 at 8:30 AM PST