Nuclear Fusion: The Basics!

Technology used in nuclear energy production is constantly evolving and being reiterated, yet there are still things that remain the same, conceptually. Currently there are two main experimental approaches used to achieve nuclear fusion: magnetic confinement and inertial confinement.

An example on how nuclear fusion works!

Magnetic confinement uses strong magnetic fields to contain the hot plasma. The magnetic field also helps control the shape and direction of plasma to reduce damage to the reactor itself. In magnetic confinement, magnets confine fusion fuel and in the process, the fuel becomes so hot that electrons break off thus causing the process of fusion to begin. There are many different devices that can be used to create those magnetic fields. Some examples are Tokamaks, Stellarators, Spheromaks, and mirror machines!

Tokamaks use the principle of charged particles reacting to magnetic forces. The strong magnetic forces constantly spin the particles in the donut shaped reactor chambers to prevent them from leaving the plasma. The Stellarator does essentially the same thing but doesn't require a transformer due to the magnets used by the Stellarator being twisted to produce a helical shape needed for energy generation. Both of them have their own strengths, Tokamaks are better at keeping the temperature of plasma while Stellarators are better at keeping the plasma stable. Currently there is ongoing research to continue to refine these devices in order to receive the best possible result with the least amount of damage!

Picture of the inside of a tokamak reactor!

Picture of a stellarator! Notice the weird shape of the metal magnet bits!

Another method used to create nuclear fusion is the process of inertial confinement. Inertial confinement is the process of compressing small pellet with fusion fuel to high densities using strong lasers or particle beams. Lasers specifically target small atoms with large lasers to cause bursts of energy, the pressure that results compresses the capsule so much that it reaches the state in which fusion occurs. Although this method has the potential for a higher energy gain, it requires an extremely high energy input as well as the need to maintain the pellet's integrity for a long period of time which leads to unique challenges. Neither the inertial confinement or magnetic confinement can be said to be better than one another due to the different unique challenges that come whether energy wise, or engineering wise.

A look into the setup of a inertial confinement machine!

There is the possibility for a new method however. There have been some exploration into the possibility of using self-generated magnetic fields created by strong electrical currents (Z-Pinch), and the use of particle accelerator technology and pistons that are currently being tested in hopes of developing these methods into a long term sustainable option. Currently the main goals and research for nuclear fusion are making advancements to maintaining fusion for longer durations of time to produce a positive net energy and to create more stable reactors that can take the long term damage and weathering that may come from the intense process and heat of nuclear fusion facilitated over long periods of time. Some of the places that are actively participating in the research and development of nuclear fusion are the Lawrence Livermore National Laboratory (LLNL) - known for their National Ignition Facility (NIF) which mostly has been working on nuclear fusion through inertial confinement. There is also ITER, which is a multinational project to build and operate a large tokamak reactor. Other places include Oak Ridge National Laboratory, Idaho National Laboratory, Los Alamos National Laboratory, and Lawrence Berkeley National Laboratory which conduct a wide range of research on nuclear fusion, from the plasma materials to magnetic fusion to the fusion blanket and fuel cycle. All of these labs play an important role within the research and development of technology and our understanding of nuclear fusion. 

Here's to hoping for an even longer nuclear fusion time being maintained and more innovation and discovery in the future! Sustainable and reliable nuclear energy through nuclear fusion is the future and this is only the beginning. With the hard work of scientists and engineers, we only get closer to getting a sustainable energy source that produces virtually 0 pollutants!