New experiments with helium-3 in a magnetic confinement tokamak have produced exciting results for the future of fusion energy, including a tenfold increase in ion energy.source: MIT
Researchers operating fusion reactor experiments at MIT, along with partnered scientists in Brussels and the U.K., have developed a new type of nuclear fusion fuel that produces ten times as much energy from energized ions as previously achieved. The experiments with the new fusion fuel, which contains three types of ions—particles with an electric charge due to the loss or gain of an electron—were conducted in MIT’s Alcator C-Mod tokamak, a magnetic confinement reactor that holds the records for highest magnetic field strength and highest plasma pressure in a fusion experiment.
The key to increasing the efficiency of the nuclear fuel was to add in trace amounts of helium-3, a stable isotope of helium that only has one neutron rather than two.Source: MIT
The Alcator C-Mod conducted its final run in September 2016, but data from experiments in the tokamak device were recently analyzed, revealing a unique type of nuclear fusion fuel greatly increases ion energies within the plasma. The results were so encouraging that researchers operating the Joint European Torus (JET) in Oxfordshire, U.K., the largest operational magnetic confinement fusion experiment in the world, repeated the experiments and achieved the same increases in energy generation.
In southern France, 35 nations* are collaborating to build the world’s largest tokamak, a magnetic fusion device that has been designed to prove the feasibility of fusion as a large-scale and carbon-free source of energy based on the same principle that powers our Sun and stars.
The experimental campaign that will be carried out at ITER is crucial to advancing fusion science and preparing the way for the fusion power plants of tomorrow.
ITER will be the first fusion device to produce net energy. ITER will be the first fusion device to maintain fusion for long periods of time. And ITER will be the first fusion device to test the integrated technologies, materials, and physics regimes necessary for the commercial production of fusion-based electricity.
Thousands of engineers and scientists have contributed to the design of ITER since the idea for an international joint experiment in fusion was first launched in 1985. The ITER Members—China, the European Union, India, Japan, Korea, Russia and the United States—are now engaged in a 35-year collaboration to build and operate the ITER experimental device, and together bring fusion to the point where a demonstration fusion reactor can be designed.
1) Produce 500 MW of fusion power
The world record for fusion power is held by the European tokamak JET. In 1997, JET produced 16 MW of fusion power from a total input heating power of 24 MW (Q=0.67). ITER is designed to produce a ten-fold return on energy (Q=10), or 500 MW of fusion power from 50 MW of input heating power. ITER will not capture the energy it produces as electricity, but—as first of all fusion experiments in history to produce net energy gain—it will prepare the way for the machine that can.
2) Demonstrate the integrated operation of technologies for a fusion power plant
ITER will bridge the gap between today’s smaller-scale experimental fusion devices and the demonstration fusion power plants of the future. Scientists will be able to study plasmas under conditions similar to those expected in a future power plant and test technologies such as heating, control, diagnostics, cryogenics and remote maintenance.
3) Achieve a deuterium-tritium plasma in which the reaction is sustained through internal heating
Fusion research today is at the threshold of exploring a “burning plasma”—one in which the heat from the fusion reaction is confined within the plasma efficiently enough for the reaction to be sustained for a long duration. Scientists are confident that the plasmas in ITER will not only produce much more fusion energy, but will remain stable for longer periods of time.
4) Test tritium breeding
One of the missions for the later stages of ITER operation is to demonstrate the feasibility of producing tritium within the vacuum vessel. The world supply of tritium (used with deuterium to fuel the fusion reaction) is not sufficient to cover the needs of future power plants. ITER will provide a unique opportunity to test mockup in-vessel tritium breeding blankets in a real fusion environment.
5) Demonstrate the safety characteristics of a fusion device
ITER achieved an important landmark in fusion history when, in 2012, the ITER Organization was licensed as a nuclear operator in France based on the rigorous and impartial examination of its safety files. One of the primary goals of ITER operation is to demonstrate the control of the plasma and the fusion reactions with negligible consequences to the environment.
The ITER fusion reactor is scheduled to turn on around 2025 and will conduct live run testing through to 2027 when it will get its first Helium-3 and again around 2029.