Note4Students

From UPSC perspective, the following things are important :

Prelims level: Fusion Energy

Mains level: Clean energy developments

fusion

US announced a “major scientific breakthrough” in the decades-long quest to harness fusion, the energy that powers the sun and stars.

What is Fusion?

Fusion works by pressing hydrogen atoms into each other with such force that they combine into helium, releasing enormous amounts of energy and heat.
This process occurs in our Sun and other stars.
Creating conditions for fusion on Earth involves generating and sustaining a plasma.
Plasmas are gases that are so hot that electrons are freed from atomic nuclei.

How is it carried out?

fusion

Very high temperature (on the order of 150,000,000° Celsius);
Sufficient plasma particle density (to increase the likelihood that collisions do occur); and
Sufficient confinement time (to hold the plasma, which has a propensity to expand, within a defined volume).

At extreme temperatures, electrons are separated from nuclei and a gas becomes a plasma—often referred to as the fourth state of matter.
Fusion plasmas provide the environment in which light elements can fuse and yield energy.

The process releases energy because the total mass of the resulting single nucleus is less than the mass of the two original nuclei.
The leftover mass becomes energy.

The US experiment uses a process called inertial confinement fusion.
It involved bombarding a tiny pellet of hydrogen plasma with the world’s biggest laser.

Carbon free: Fusion Reactions could one day produce nearly limitless, carbon-free energy, displacing fossil fuels and other traditional energy sources.
Efficient: Net energy gain has been an elusive goal because fusion happens at such high temperatures and pressures that it is incredibly difficult to control.
Clean: Unlike other nuclear reactions, it doesn’t create radioactive waste.

Significant though the achievement is, it does little to bring the goal of producing electricity from fusion reactions any closer to reality.
By all estimates, use of the fusion process for generating electricity at a commercial scale is still two to three decades away.
The technology used in the US experiment might take even longer to get deployed.

International Thermonuclear Experimental Reactor (ITER) is one of the most ambitious energy projects in the world today.
The idea for an international joint experiment in fusion was first launched in 1985.
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.
ITER is funded and run by seven member parties: China, the European Union, India, Japan, Russia, South Korea and the United States.