Japan's fusion experimental device "JT-60SA"

According to Japanese media reports, the practical application research of "fusion power" has reached an important milestone. In the autumn of 2022, the National Institute for Fusion Science (NIFS) operated the world's largest fusion experimental device, JT-60SA (SA). In addition, it is expected to play a role in promoting human resource development by supplementing international projects through the use of the International Thermonuclear Experimental Reactor (ITER) being constructed in France. Research and development related to fusion power is accelerating overseas, and business opportunities have expanded to related component businesses.

Fusion Power

The nuclear fusion reaction between deuterium and tritium atomic nuclei with plasma produces heat used for electricity generation. It is expected to be a next-generation energy source that does not emit carbon dioxide (CO2) during the power generation process. It continues to maintain a plasma at 100 million degrees Celsius and constantly undergoes nuclear fusion reactions. Unlike nuclear power generation, which produces energy through continuous reactions of uranium-235, fusion power is considered highly safe because the reaction stops if the plasma cannot be maintained. The main theories were developed in the 1970s, and subsequent practical application research was conducted both domestically and internationally.

Expectations for Promoting Human Resource Development

"For a long time, people said that fusion power would be '30 years away, and then another 30 years.' Seeing the construction of SA and ITER become real made me deeply moved," said Koichi Omochi, a senior expert at Toshiba Energy Systems (Kawasaki City, Sakai Ward), recalling the hardships so far.

The Japan Atomic Energy Agency will build the SA, which involves Japan and Europe, at the Naka Institute (Naka City, Ibaraki Prefecture), and it will start operation as early as autumn. The "cryostat" that houses the vacuum vessel is approximately 15 meters and 50 centimeters tall and about 13 meters and 40 centimeters in diameter. Before the completion of the reactor, it will be the world's largest fusion power experimental facility.

In fusion power facilities, the coils that control the plasma are particularly important. In Eater and SA, beams and microwaves are used to heat the plasma to produce it. The plasma continues to float within the "magnetic cage" generated by the coils. This is because if the plasma, which reaches up to 100 million degrees Celsius, comes into contact with the vacuum vessel in the fusion reactor, the equipment will be damaged.

(From left) Expert Hayakawa, Senior Expert Omochi

Controlling the plasma is difficult, and the quality requirements for each component are strict. The "toroidal magnetic coil" composed of seven coils is difficult to manufacture, and "each piece delivered to the feeder must have an error of less than one millimeter" (many senior experts). The welding of the vacuum container also requires "millimeter-level adjustments," said Toshiba Energy Systems expert Hayakawa Atsuro. SA is the culmination of accumulated expertise so far.

The purpose of SA is to conduct experiments that Eater cannot complete. The engineering design of Eater was completed over 20 years ago in 2001. "Eater does not include the latest knowledge, and SA will supplement it," explained Dr. Yoshitaka Ikeda, Director of the Naka Institute. For example, the company plans to conduct research on increasing plasma density to improve the efficiency of the fusion reaction.

A beam injection device used to heat the plasma

Meanwhile, the Rokkaku Institute of the Six-Point Area, located in Rokkaku Village, Aomori Prefecture, is conducting research on high-temperature resistant materials. The operation of SA is also a valuable opportunity for human resource development. According to Director Ikeda, "I hope young researchers from Japan and Europe gather around the Naka Institute to promote fusion research."

ITER is an international project involving Japan, Europe, the United States, Russia, China, India, and South Korea. It is planned to start operations in 25 years to generate and maintain plasma experiments, and in 35 years to begin combustion tests for causing nuclear reactions. SA will cooperate with this. Additionally, there is the operation of a "prototype reactor" to demonstrate power generation. The Japanese government has set a goal of operating a prototype reactor by 50 years.

Activities in other countries are also active. The UK plans to build a fusion power plant around the year 40. The US announced a 10-year plan to accelerate fusion research. It aims to involve private companies to commercialize the technology.

Private investment has increased to over 34 billion yen over the past 21 years, and investments in startups are also progressing. Commonwealth Fusion Systems and TAE Technologies each successfully raised over 10 billion yen.

Commercialization by the private sector is expected to begin in the 30s. General Fusion Canada has reached an agreement with the UK Atomic Energy Authority (UKAEA) to build a demonstration plant. The plan is to start production in 25 years, aiming to quickly commercialize it.

Business opportunities in related areas are also expanding. Kyoto Fusion Ring, a startup from Kyoto University, specializes in parts that extract heat and generate electricity. The company plans to build a simulation factory to test the performance of parts and try to capture commercial demand. "Consultation from overseas startups has already increased," said CEO Takashi Nagao.

Regarding components, this is a field where Japan can fully utilize the knowledge accumulated in Eater and SA. Ikeda emphasized, "Japan's advantage lies in being able to consistently carry out all work from research to development and manufacturing."

Long-term research requires government support

Japan's fusion power is steadily advancing, but there are challenges. One is the lack of guidelines for safety regulations. The United Kingdom will determine the direction of safety regulations and encourage the private sector to conduct R&D in a healthy manner. On the other hand, Japan has not yet provided a direction, and according to Nagao, "the private sector finds it difficult to develop plans for building experimental reactors and commercial reactors." Helical Fusion, a startup that aims to commercialize a helical fusion reactor, has complained about the inconvenience caused by the lack of safety regulatory guidelines. The company was founded by researchers from the National Institute for Fusion Science. Currently, the company is developing parts to extract heat. The goal is to start generating power in a 100,000 kW fusion reactor around the year 40.

Another important issue is how to sustain R&D over the long term while addressing funding issues. Masato Matsuo, CEO of EX-Fusion (Suita City, Osaka Prefecture), emphasized, "We need to consider applying the technology cultivated through fusion to other fields." The company develops laser fusion, which involves irradiating lasers to heat deuterium and tritium fuel to cause a fusion reaction. Knowledge gained from this research will be applied to semiconductor manufacturing, "we will create a stepping stone for fusion, which takes time," said Matsuo, the CEO.

Special metal developed by Yamato Alloy

President Genjiro Hagiya of Yamato Alloy, a company producing special metals, also predicted, "Fusion has a long way to go, and this technology will be applied to other fields." When Toshiba Energy Systems is not involved in fusion-related work, it maintains its knowledge by allocating human resources to superconducting, accelerator, and nuclear power generation businesses.

Continuing long-term R&D through private efforts alone has its limits. The realization of fusion power also requires government support to support private ingenuity.

"Mitsubishi Heavy Industries, Looking Ahead to the Prototype Reactor"

As research and development for the practical application of fusion power becomes increasingly active, some researchers have mixed feelings about the Eater project, which forms the core of the project. He is Masahiko Ito, head of the fusion promotion department at Mitsubishi Heavy Industries, who has been engaged in fusion research for about 30 years. "It's a pity that Japan doesn't have the legacy of large-scale devices like Eater," he said. Behind his emotions is a sense of pride that "Japan leads in the field of fusion."

Mitsubishi Heavy Industries is responsible for manufacturing 19 parts called inner toroidal magnetic coils, which are delivered to Eater. The precision of the same part is about 10 meters and requires a high precision of 1 millimeter. Ito talked about the difficulty of manufacturing, saying, "Once you make large and high-precision parts for the reactor, there's no turning back."

The component that extracts helium gas and unburned fuel from the nuclear fusion reaction, the "divertor," has passed the world's first high-temperature addition test. In addition to being able to withstand temperatures above 1000 degrees Celsius, it also needs to establish a connection technology between different materials. The company has been making models since the 1990s and has already been able to achieve them.

Director Ito looked at the prototype reactor. "The prototype reactor has different difficulties from the reactor, but fusion is a type of nuclear reactor. That's why we have kept our plant technology alive. We are considering a fuel cycle system that produces tritium, a fuel, and an integrated fusion reactor and power generation system. The company will use the knowledge accumulated in the nuclear power business. In terms of component manufacturing, he also expects to reduce commercialization costs, saying, "If we use the knowledge after completing the design of the reactor, we can slightly reduce the precision. We are also considering acquiring the professional knowledge of local manufacturing buildings used in Eater. Therefore, we plan to maintain human resources and expertise by developing other innovative reactors and replacing parts of overseas nuclear power plants. In addition, we will capture the realization of fusion, the "dream energy".

Original article: https://www.toutiao.com/article/7545090204253422114/

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