Electricity is essential for our daily lives. You need it for your cellphones, computers, lightbulbs, and other electronic devices. The more people use these devices, the more electric power we need to produce. Nuclear Fusion reaction has been studied as an alternative way to produce power for a long time because it will produce lots of energy with little radioactive waste.
Nuclear fusion is essentially the combination of two lighter elements to form a heavier element. In this process, the sum of the mass of the reacted elements is greater than the mass of the forming heavier element. The difference in mass will turn into the energy produced according to equation ∆E=∆mc^2. The recent nuclear power plants utilize nuclear fission reaction, in which heavier nuclei will split into lighter nuclei. Products of nuclear fission might be radioactive, pose a threat to living things, and pollute to the environment. Nuclear fusion reaction, on the other hand, won’t produce such a radioactive products. However, because the positively charged nuclei will repel each other, the scientists have to use enormous amounts of energy, which may cost lots of money, to accelerate the lighter elements to make them acquire enough speed to collide. Theoretically, this nuclear fusion reactions also only occur at temperature of 150 million degree Celsius.
A massive nuclear fusion reactor, called tokamak, is now being constructed in France. The project’s name is ITER, which stands for International Thermonuclear Experimental Reactor. The European Union, the United States, China, Japan, India, South Korea, and Russia collaborated in the project. Its goal is to prove that the nuclear fusion is possible as the means to provide power in future.
The machine, the tokamak, was first developed in Russia. In the tokamak, there will be plasma of light elements, usually hydrogen atoms with different mass, or isotopes of hydrogen. The electric current and the extremely strong magnetic field in the tokamak will heat the plasma, and as the plasma move at high speed, the magnetic field in tokamak will “confine” its path to keep it from touching the walls of the tokamak.
As the goal of ITER is only to prove the possibility for nuclear fusion reaction as a way to produce enormous amount of energy, the tokamak in France will not be connected to a power supply system. However, its success will allow people to know that nuclear fusion is a potential way to generate electric power without using fuels or producing radioactive pollution, and then scientists can design other nuclear fusion power plants. Scientists at the Joint European Torus (JET) said that in June they will start fusing tritium and deuterium, which are the isotopes of hydrogen. This year, on March 29, researchers at DIII-D National Fusion Facility, operated by General Atomics, a defense and diversified technologies company, released their first design of compact fusion reactor for the Compact Advanced Tokamak (CAT) concept. To make nuclear fusion power more commercial, scientists now also study how to create a nuclear fusion reaction at a temperature that is closer to room temperature. This process is called cold fusion, and the lower temperature means less energy used and less costs. There is promise nuclear fusion can be a new way to generate the electricity we need in our daily lives!