This is an enlarged view of the X-ray photoelectron spectroscopy system used at the Idaho National Laboratory to measure the surface chemistry of potential candidate materials for fusion.
Masashi Shimada I have been studying fusion since 2000 when I participated in the graduate program at the University of California, San Diego. He is currently the Chief Scientist at the Safety and Tritium Applied Research (STAR) facility at the Idaho National Laboratory, one of the federal government’s major scientific laboratories.
The field has changed a lot.
Early in his career, fusion was often a joke, even if it was discussed. “Nuclear fusion is the energy of the future, and it will continue to be so,” Shimada always heard.
But it’s changing. Dozens of start-ups Raised nearly $ 4 billion in private funding, according to Fusion Industry Association,Industry group.
Investor and Department of Energy Secretary Jennifer Granholm Fusion energy is called the “Holy Grail” of clean energy.It has the potential to provide almost infinite energy, without emitting greenhouse gases and without the same kind of long-lasting radioactive waste as fission.
There is a good harvest of new young scientists working on fusion, and they are inspired.
“When I talk to young people, they believe in fusion. They are trying to achieve that. They have a very positive and optimistic mindset,” said Shimada.
Shimada and his team are currently studying the management of tritium, a popular fuel pursued by many fusion startups, in the hope of establishing the United States for a bold new fusion industry. I am doing.
“As part of the government’s new” bold vision “for the commercialization of fusion, the handling and production of tritium will be an important part of their scientific research,” he said. Fusion Industry Association I told CNBC.
Masashi Shimada
Photo courtesy of Idaho National Laboratory
Tritium supply chain research
Fusion is a nuclear reaction when two light nuclei are pushed together to form one heavy nucleus. It emits “a large amount of energy”. It’s how the sun is powered. However, controlling fusion reactions on Earth is a complex and delicate process.
Often, the fuels for fusion reactions are deuterium and tritium, both in the form of hydrogen. The most abundant element in the universe..
Deuterium is very common and is found in seawater. If large-scale fusion is achieved on Earth 1 gallon of seawater According to the Ministry of Energy, there is enough deuterium to make as much energy as 300 gallons of gasoline.
However, tritium is not common on earth and needs to be produced. Shimada and his research team at the Idaho National Laboratory have a small tritium laboratory 55 miles west of Idaho Falls, Idaho, where they are studying isotope production methods.
“Tritium isn’t available in nature and needs to be created,” Shimada told CNBC.
Most of the tritium currently used in the United States National Atomic Energy Institute of CanadaSaid Shimada. “But we can’t really rely on those supplies, because once used, we basically run out of all the tritium if we don’t recycle it,” Shimada said. “So we have to make tritium while running the fusion reactor.”
Shimada said there is enough tritium to support pilot fusion projects and research, but hundreds of reactors will be needed to commercialize it.
“”Therefore, to create and recycle tritium, you need to invest in tritium fuel cycle technology right now.
Chaistyler, a scientist at the Idaho National Laboratory, is measuring the surface chemistry of materials that may be used for fusion with X-ray photoelectron spectroscopy.
Photo courtesy of Idaho National Laboratory
Safety protocol
Tritium is radioactiveHowever, it is not the same method as fuel for fission reactors.
“The radioactive decay of tritium takes the form of a weak beta radiator. This type of radiation can be blocked by a few centimeters of water,” he said. World Nuclear AssociationTold CNBC.
Cobb explained that the half-life, or half of the radioactive material, takes about 12 years to decay, and when it decays, the product released is non-radioactive helium.
By comparison, the fission reaction divides uranium into products such as iodine, cesium, strontium, xenon, and barium. These products themselves are radioactive and have a half-life of days to tens of thousands of years.
However, tritium is radioactive, so it is necessary to study the behavior of tritium. In particular, the Idaho National Laboratory is studying how tritium interacts with the materials used to build machines, including fusion. Often this is a donut-shaped machine called a tokamak.
In order for the fusion reaction to occur, the fuel source must be heated. plasma, The fourth state of matter. Shimada said these reactions occur at very high temperatures of 100 million degrees Celsius and can affect the amount and rate of tritium entry into the plasma-holding material.
Most fusion reactors are made of special stainless steel with a thin layer of tungsten inside. “Tungsten was chosen because it has the lowest tritium solubility of all the elements in the periodic table,” says Shimada.
However, high-energy neutrons generated from fusion reactions can also cause radiation damage to tungsten.
Here, at the Idaho National Laboratories, Sandia National Laboratories collaborator Rob Kolasinsky uses a glove box for tritium plasma experiments.
Photo courtesy of Idaho National Laboratory
The team’s research aims to provide the fusion enterprise with a dataset to understand when it will happen, so the safety of the program can be established and measured.
Shimada told CNBC about the materials used to contain the fusion reaction, “probably without much worry, the fusion reaction can take place for 5 to 10 seconds.” However, commercial-scale energy production requires the fusion reaction to be maintained at high temperatures for many years at a time.
“The goal of our research is to help fusion reactor designers predict when tritium buildup in materials and tritium penetration through vessels will reach unacceptable levels,” says Shimada. I told CNBC. “In this way, you can set up a protocol that heats (ie, burns) the material and removes tritium from the container, reducing the risk of tritium being released in the event of an accident.”
The Idaho National Laboratory is investigating the behavior of tritium to establish safety standards for fast-growing industries, but its waste is far less problematic than today’s fission-powered nuclear facilities. is. The federal government has been researching ways to create permanent fission-based waste reservoirs. Over 40 yearsAnd haven’t come up with a solution yet.
“Fusion does not produce long-lived radioactive nuclear waste, which is one of the advantages of fusion reactors over fission reactors,” Shimada told CNBC.
