ITER

ITER stands for International Thermonuclear Experimental Reactor. It is a big science project to test if we can make energy from joining tiny particles together, called nuclear fusion. The ITER project is being built near Cadarache in southern France. Building started in 2013, and scientists hope to create their first small sun, called plasma, in the years 2033–2034. When that happens, ITER will be the largest fusion machine ever made, with a space for plasma six times bigger than the largest one before it in Japan.

The main goal of ITER is not to make electricity right now but to show that a big fusion machine can work. Scientists want to learn how to control very hot plasma, test new technologies like special magnets and cooling systems, and make sure a fusion power plant could be safe. They also want to test how to make more of a special material called tritium that is needed for fusion.

Many countries work together on ITER, including China, the European Union, India, Japan, Russia, South Korea, and the United States. Other countries like Australia, Canada, Kazakhstan, Switzerland, Thailand, and the United Kingdom also help in different ways. Building ITER has cost a lot of money—estimates range from €18 billion to much more—and it is one of the most expensive science projects ever. After ITER, scientists plan to build an even bigger machine called DEMO that could actually make electricity from fusion.

Background

Fusion tries to copy what happens in stars. In stars, super hot conditions push tiny parts of atoms together, making a lot of energy as heat and light. If we could do this on Earth, it could give us lots of clean energy.

Unlike regular nuclear power, which splits atoms apart, fusion puts atoms together using very high heat. This can give us energy with very little pollution. One of the goals of the ITER project is to use a special mix of atoms that gives the most energy. Building ITER has taken many years and a lot of money. The project started in 2013 and is still being built today near Cadarache in France. Scientists hope to learn more about how to make fusion power work well for the future.

Organisation history

The idea for ITER started in 1978 with a project called INTOR, involving the Soviet Union, the European Atomic Energy Community, the United States, and Japan. The project slowed down until 1985 when Soviet leader Mikhail Gorbachev met with French President François Mitterrand and then Ronald Reagan at the Geneva Summit. They talked about working together on a new way to get energy from nuclear fusion.

Two scientists, American Alvin Trivelpiece and Russian Evgeny Velikhov, thought that all countries should work together on building a fusion reactor. They believed no single country could afford it alone. After discussions between leaders, the US decided to join the project. In 1986, four groups — Europe, Japan, the USSR, and the US — formed a committee to guide the project. By 1987, they named it the International Thermonuclear Experimental Reactor, or ITER, meaning "the way" in Latin.

Over the years, more countries joined, including China, South Korea, India, Australia, Kazakhstan, and Canada. In 2005, it was decided to build ITER in France. Construction began in 2007, and assembly started in 2020.

Directors-General

ITER is led by a group called the ITER Council, made up of representatives from the seven countries that agreed to work together on this project. The Council makes big decisions and chooses the director-general to lead the project. So far, there have been five directors-general.

Bernard Bigot became director-general in 2015 to help improve how ITER is managed. He was chosen again in 2019 for another five years. Sadly, he passed away in 2022, and Eisuke Tada temporarily led the project until a new director-general was chosen.

Objectives

ITER aims to show that fusion power can work as a big, clean energy source. The project wants to create a special kind of energy called fusion plasma that is ten times stronger than the energy put in for a short time. It also wants to keep this energy going steadily for up to 8 minutes.

The project will test important technologies like special magnets and robot maintenance. It will also study how to create a material called tritium and how to handle the energy from fusion reactions. All of this helps countries work together and build skills for future fusion power plants.

fusion energy gain factor superconducting magnets remote handling tritium breeding

Timeline and status

As of April 2022, ITER was about 85% done toward its first test run. Originally, this test run was set for late 2025, but in 2023, delays were expected. In July 2024, ITER shared a new plan. It now aims to start operations with a special type of energy in 2034, followed by more advanced tests in 2035 and even more in 2039.

The idea for ITER began in 1978 when the European Commission, Japan, United States, and USSR worked together on a project called the International Tokamak Reactor Workshop. This meeting was held under the International Atomic Energy Agency and aimed to see if fusion energy could be used for power and what more research was needed. Many scientists and engineers from each country studied how to contain fusion energy and design ways to use it.

In 1985, during a meeting in Geneva, a leader suggested that two countries work together on building a fusion energy machine. The ITER project officially started in 1988. Construction began in 2007, and building the main structure started in 2013.

Building began in July 2020. Once finished, ITER will be the largest machine for studying fusion energy, with a space for the energy to grow much bigger than any before. In 2023, a decision was made to change a part of the machine from a material called beryllium to tungsten, because beryllium can be dangerous and might break during tests.

In July 2024, the leader of ITER shared that the first test run will now happen no earlier than 2033. Getting the machine ready for full use will also take longer, to at least 2036. Fixing some parts that weren’t working right was expected to cost a lot of money.

Reactor overview

See also: Nuclear fusion

When deuterium and tritium come together, they create a helium nucleus and a high-energy particle called a neutron.

Fusion can produce a lot of energy. In stars, fusion creates energy, and on Earth, it could help us make electricity. To make fusion happen, the tiny parts inside atoms need to get very close to each other. But they push away from each other because they have the same charge. So, they need a lot of energy to come close enough to fuse. In the ITER project, very high temperatures are used to give these parts enough energy. The ITER project uses special magnets to keep the hot, charged particles in place so they can fuse.

At these high temperatures, the particles move very fast and could escape if not contained. ITER uses magnetic fields to keep the particles from flying away. The project also tests materials that can handle the tough conditions inside a fusion reactor. Neutrons, which carry most of the energy from fusion, will be a main source of energy output in ITER. The project will also test ways to create new fuel from these neutrons.

Technical design

The vacuum vessel is the central part of the ITER machine: a double-walled steel container in which the plasma is contained by means of magnetic fields. The ITER vacuum vessel will be twice as large and 16 times as heavy as any previously manufactured fusion vessel.

ITER will use deuterium-tritium fuel. The magnet system used in the ITER tokamak will be the largest superconducting magnet system ever built.

To achieve fusion, plasma particles must be heated to temperatures that reach as high as 150 million °C. To achieve these extreme temperatures, multiple heating methods must be used.

The ITER cryostat is a large stainless steel structure surrounding the vacuum vessel and the superconducting magnets, with the purpose of providing a super-cool vacuum environment.

The divertor is a device within the tokamak that allows for removal of waste and impurities from the plasma while the reactor is operating.

The ITER tokamak will use interconnected cooling systems to manage the heat generated during operation.

Location

The choice of where to build ITER took a long time. Japan suggested a place called Rokkasho. Europe looked at two spots: one in Cadarache, France, and another in Vandellòs, Spain. In November 2003, Europe chose Cadarache. Canada also suggested a site in Clarington in May 2001 but decided not to continue in 2003.

Finally, the decision was between France and Japan. On 28 June 2005, leaders agreed to build ITER in Cadarache, France, with Japan getting special roles and money to build facilities in Japan.

The group in charge of Europe’s part, called Fusion for Energy, is in Barcelona, Spain. Another important place for testing is being built in Padua, Italy.

Most buildings at ITER will have a special look with shiny steel and grey metal to match the area and keep the buildings cool.

Participants

ITER is a big science project with many countries working together. Right now, seven main countries and groups are part of it: China, the European Union, India, Japan, Russia, South Korea, and the United States.

Some other places, like Australia, Canada, Kazakhstan, and Thailand, help out too, even though they are not full members. They share ideas and work together in special ways. The project is led by a group called the ITER Council, which makes big decisions about how things run.

Domestic agencies

Each member of the ITER project has created its own agency to help build and support the project. These agencies have their own staff and budgets and manage contracts for building parts of the reactor.

The European Union’s agency, called Fusion for Energy, is based in Barcelona, Spain. It helps design and build important parts like the vacuum vessel and magnets. China’s agency works on parts such as magnets and the first wall, and also runs experiments in Chengdu and Hefei. India’s agency, based in Ahmedabad, helps build parts like the cryostat and cooling systems. Japan’s agency, based in Chiba, helps design and build parts like the central solenoid coils and plasma diagnostics. Korea’s agency, based in Daejeon, works on parts like sections of the vacuum vessel and the tritium storage system. The Russian Federation’s agency helps supply special equipment and conductors for the magnetic system. The US agency, based at Oak Ridge National Laboratory in Tennessee, helps design and build parts like the tokamak cooling system and magnet systems.

Funding

In 2006, leaders signed an agreement to build a special science project called ITER. They thought it would cost about €5.9 billion over ten years. But by 2008, they realized it would actually cost closer to €19 billion. By 2016, the cost had gone up even more, to over €22 billion.

The money for ITER comes from many countries working together. The European Union, where the project is being built, agreed to pay the biggest share. Other countries like China, India, Japan, South Korea, Russia, and the United States also help pay. Most of the money is given as materials and services instead of cash, using something called ITER Units of Account.

The United States has changed how much it pays over time. In 2018, the country increased its support to help finish the project. Europe also adjusted its budget several times to make sure ITER could be built properly.

Manufacturing

Building the ITER tokamak is like putting together a giant three-dimensional puzzle. Parts are made all around the world and then brought to France to fit together. This way of building helps share skills and boost economies for the countries involved.

Many companies and groups have worked on ITER. In Europe, big contracts have gone to teams from different countries. In America, companies like General Atomics are making important parts. China, Russia, India, and Japan are also helping by making different pieces for the project. While there have been some delays, the team hopes to start testing in the 2030s.

Criticism

The ITER project has faced some criticism. Some people worry about possible environmental effects and whether it will help fight climate change. When France was chosen as the location in 2005, some European environmentalists opposed it. One French politician thought money should go to fighting global warming instead. However, another group supported ITER as a way to address climate change.

Some researchers believe other fusion projects could be cheaper and more effective than ITER. There have also been concerns about the design of the tokamak, especially after a 2013 study showed the power load on a part called the divertor would be much higher than expected.

Critics also worry about the supply of tritium, a material needed for the experiment. ITER will use all existing tritium supplies, and current technology cannot produce enough for future projects.

Supporters argue that much of the criticism is not accurate. They say fusion power would produce much less radioactive waste than traditional nuclear power and would not create materials for weapons. They also believe fusion power could provide reliable electricity with almost no pollution. Supporters say that testing materials under intense conditions is necessary to understand how fusion power could work, and that ITER is a vital step in this research. They point out that fusion has the potential to be a clean energy source with many benefits.

Similar projects

Before ITER, there were other important projects like JET, Tore Supra, MAST, SST-1, EAST, and KSTAR. Today, scientists are also working on new ideas for fusion reactors, such as NIF, W7X, T-15MD, STEP, SPARC, SST-2, CFETR, DEMO, and K-DEMO, among others. These projects help researchers learn more about how to create clean energy from fusion.