Fusion, as the name suggests, it means fusing or combining of two atoms or more atoms to form one or more new atom. The difference in the energy of the atom which was fused and the product is the energy released by the reaction.
At present, we are using nuclear fission to create electricity. In nuclear fission, we bombard a heavy element with a neutron which splits the atom into several lighter atoms and produces a large amount of energy with gamma photons and free neutrons.
The limitation of nuclear fission, which nuclear fusion will solve is the production of the nuclear waste. Nuclear waste is the resultant radioactive waste after a fission reactant. This can be hazardous if not disposed of properly. Also, the half-life of the byproducts of the nuclear fission reaction is 10,000 years.
The anticipation of the Nuclear Fusion reaction is on for years now. The major led back is our technology is currently not advanced enough to hold a stable reaction. A stable nuclear reaction means to create our own mini sun on earth. And it’s HARD. Currently, we have just held a stable nuclear fusion reaction for just 5sec that with supplying more power than getting out of it, which means, as you have guessed, is useless.
To achieve stable fusion reactions, we need super high temperature approximately 6 times the temperature of the sun’s core which comes close to 100 million Kelvin. At this temperature hydrogen isn’t a gas, it becomes plasma.
Plasma doesn’t exist on earth under normal condition. It is the state in which the gas becomes ionised and start conducting electricity, which was initially an insulator. Lighting is one of the examples of partially ionised plasma.
For the confinement of the nuclear fusion, at such high temperature we need special techniques. Magnetic Confinement Fusion is one of them and this approach dates back to 1940s. Magnetic Confinement Fusion uses a magnetic field to generate thermonuclear fusion power.
Tokamak is a device based on Magnetic Confinement fusion. Invented by Soviet physicists, Igor Tamm and Andrei Sakharov, this is one of the leading candidates for fusion reactor and projects like ITER and private companies like General Fusion are using some modification of this device.
ITER or International Thermonuclear Experimental Reactor is the world’s largest nuclear fusion research located in France. This has been designed so that it can output 500 megawatts while only consuming 50 megawatts, but all that is theoretical for now. The project is funded by The Europian Union, India, Japan, China, Russia, South Korea and the US.
General Fusion is a private company created for the development of fusion power. Headquartered in British Columbia, Canada; they use spherical tokamak. A spherical tokamak is spherical, obviously. This design reduces the size of the hole, resulting in a plasma shape that is almost spherical.
Fusion energy features numerous qualities. It is a holy grail of energy and provides a nearly unlimited energy source that does not generate
any greenhouse gas effect or environmental pollution,
and it features undeniable advantages in terms
of safety. With adequate design, radioactive wastes
from the operation of a fusion plant should not
constitute a burden for future generations.