Creating a sun in the lab and its significance
- China and the European Union has recently experimented in the direction of creating an artificial sun on earth that can produce energy from the same process that gives starlight and sunshine
- These experiments are for the upcoming International Thermonuclear Experimental Reactor (ITER)
- It is a global experiment to generate 500 MW of power by fusing hydrogen atoms into helium atoms by 2035.
Experiments of China and Russia
- Experimental Advanced Superconducting Tokamak (EAST),2022: it was conducted by China
- It sustained the plasma at 70 million degrees Celsius for 1,056 seconds
- Joint European Torus (JET) fusion experiment: it was conducted by the European Union in Oxfordshire, U.K.
- It produced 59 megajoules (MJ) of energy from thermonuclear fusion.
Thermonuclear fusion
- In a thermonuclear fusion reaction, lighter atoms like those of hydrogen fuse to produce slightly heavier atoms like that of helium.
- The mass of one hydrogen atom is 1.007825 Atomic Mass unit (AMU).
- When four hydrogen atoms are combined, it transmutes into a helium atom.
- The sum of the mass of four hydrogen atoms is 4.03130 AMU, while the mass of one helium atom is just 4.00268 AMU.
- As the matter is neither created nor destroyed; hence the mass difference 0.02862 AMU is converted into pure energy by way of Einstein's famous formula E=mc2.
- Example: If four grams of hydrogen is fused into helium, about 0.0028 grams of mass would be converted to 2.6x10^11 joules; with that energy, a 60-watt light bulb can be enlightened for over 100 years
Environmental benefits of fusion
- Unlike the fission reactors, like the ones in Kalpakam and Koodankulam, the fusion reactors do not pose the dangers of a radioactive leak.
- The thermonuclear power produces four million times more energy than burning coal.
- The only waste product from it is harmless helium.
History of efforts to achieve nuclear fusion
- Proyecto Huemul,1951: Argentinia tried to harness energy from fusion but it failed
- Both the USSR and the U.S. stepped up their fusion research
- The Soviets came up with a viable design the Tokamak to kindle and sustain nuclear fusion
Tokamak
- The Tokamak is an acronym for tongue-twisting Russian terms 'toroïdalnaïa kameras magnitnymi katushkami', which means ""toroidal chamber with magnetic coils"".
- Theory: If fusion has to occur, the first step has to be the creation of hot plasma.
- Heating a tiny pellet of hydrogen to millions of degrees and generating plasma can be done by the lasers. However, to keep the fiery plasma at millions of degrees from touching the container wall is tough .
- Soviet physicists conceptualized that if one can create a magnetic field in the shape of a torus like a south Indian vada then the scorching plasma could be contained in the invisible magnetic bottle and the scalding of the walls of the container could be prevented
- Based upon this theory, an experimental reactor was built and demonstrated by a Soviet team
- Thirty-five countries, including India, Russia, the United States, the United Kingdom, China, European Union, are collaborating to jointly build the largest Tokamak as part of the International Thermonuclear Experimental Reactor (ITER).
Significance
- To create plasma for fusion, the mixture of deuterium and tritium needs to be heated to temperatures 10 times hotter than the Sun's center.
- The heat must be removed from the reaction to boil water, produce steam and turn a turbine to generate electricity.
- The plasma at high temperature needs to be sustained for a long time if commercial energy has to be obtained.
- Making plasma at higher and higher temperatures and sustaining it at that temperature for more and more time will provide insights on disruptions in the experiment
- The Chinese accomplishment of maintaining 2.8 times the Sun's temperature for 17 minutes is a milestone in this direction.
- For the first time, the Joint European Torus experiment used the tritium fuel mix, the same one that will power ITER.
- They could harvest one-third of the input energy as an output, a significant step from earlier results.
- The experimental results from this JET indicate that the models used to design ITERare robust
- These experiments would help validate ITER's designs.
India’s efforts in the field of Thermonuclear fusion
- Homi J. Bhabha proposed in the first 'Atoms for Peace' meeting in Geneva in 1955 that the future in energy will come from thermonuclear fusion
- The Institute for Plasma Research (IPR) in Gandhinagar and the Hot Plasma Project at Saha Institute of Nuclear Physics (SINP), Kolkata are leading the nuclear fusion research in India