The world’s largest fusion reactor is put into operation in Japan
On Friday, the world’s largest experimental fusion reactor was inaugurated in Japan.
This technology is still in its infancy, but some consider it to be the answer to the future energy needs of humanity. Fusion differs from fission, the method currently used in nuclear power plants, in that it involves the fusion of two atomic nuclei instead of splitting one.
The purpose of the JT-60SA reactor is to study the possibility of fusion as a safe, large-scale and carbon-free source of clean energy, which produces more energy than is consumed in its production. The six-story machine, located in a hangar in Naka, north of Tokyo, is a donut-shaped tokamak that contains swirling plasma heated to 200 million Celsius (360 million Fahrenheit).
This is a joint project of the European Union and Japan, which is the predecessor of its older brother in France, the International Thermonuclear Experimental Reactor (ITER) under construction. The ultimate goal of both projects is to persuade the hydrogen nuclei inside to combine into one heavier element, helium, releasing energy in the form of light and heat and mimicking the process that occurs inside the Sun.
Researchers at ITER, which is over budget, behind schedule, and facing serious technical challenges, hope to achieve the holy grail of nuclear fusion technology: clean energy. Sam Davis, deputy project manager of the JT-60SA, said that this device “will bring us closer to fusion energy.”
“This is the result of the collaboration of more than 500 scientists and engineers and more than 70 companies across Europe and Japan,” Davis said at the inauguration on Friday.
EU Energy Commissioner Kadri Simson said that the JT-60SA is “the most advanced jet in the world,” calling the start of operation “a milestone in the history of fusion.”
“Fusion has the potential to become a key component of the energy mix in the second half of this century,” Simson added.
The “net energy gain” feat was achieved last December at the National Ignition Facility at Lawrence Livermore National Laboratory in the United States, home to the world’s largest laser. The US facility uses a method different from ITER and JT-60SA, known as inertial confinement fusion, in which high-energy lasers are directed simultaneously into a thimble-sized cylinder containing hydrogen.
The U.S. government called the result a “landmark achievement” in the search for a source of unlimited clean energy and an end to dependence on fossil fuels that emit carbon dioxide, which causes climate change and geopolitical turmoil.
Unlike nuclear fission, fusion does not carry the risk of catastrophic nuclear accidents – such as the one in Fukushima, Japan, in 2011 – and produces much less radioactive waste than current power plants, its supporters say.
