Editorial Feature

What is Laser Fusion?

Laser Fusion - Does this technology represent a clean tomorrow?

Laser Fusion - Does this technology represent a clean tomorrow? Image Credits: sxc.hu

Recently, there has been a lot of discussion regarding the development of an 'invisibility time cloak' using laser pulses to manipulate light. This technology represents the potential for laser technology although one other major development, laser fusion is something that could benefit all mankind in the not to distant future.

Fusion is the reaction in which two atoms of hydrogen combine to form a helium atom. During this process, hydrogen is converted into energy, potentially giving this fusion technique the potential to serve as an inexhaustible energy source.

Laser fusion, also known as 'inertial confinement fusion', is a method of initiating nuclear fusion reactions through heating, and compressing, fuel targets in the form of pellets containing deuterium and tritium.

It is one of the most-promising approaches to achieving controlled thermonuclear fusion. Think of laser fusion as being similar to that of the internal combustion engine approach to release nuclear fusion energy.

Laser fusion attempts to achieve nuclear fusion in small pellets of deuterium-tritium mixture at high energy density.

Although high energy laser fusion experiments began in early 1970s, Shiva and Nova developed at Lawrence Livermore Laboratory are the first experimental laser fusion devices that started operation in 1978. They employ neodymium glass laser capable of producing extremely high power pulses.

During laser fusion, small pellets of deuterium-tritium (DT) isotopes are introduced into a blast chamber where the pellets are compressed to high densities using an intense laser.

This technique employs a single laser beam that is divided into a number of beams which are amplified and passed into the chamber.

Laser Inertial Fusion Energy (LIFE) - A modular fusion chamber design to reduce costs and speed maintenance

Laser Inertial Fusion Energy (LIFE) - A modular fusion chamber design to reduce costs and speed maintenance. Image Credits: lasers.llnl.gov

The combination of high density and heat due to compression, induces the thermonuclear explosion ignition.

The kinetic energy produced by the reaction products such as charged particles, x-rays and neutrons is stored as heat in a blanket that serves as a source in a steam thermal cycle to generate power.

The compression of the DT pellet can be carried out using two approaches: direct and indirect-drive laser fusions.

In direct-drive laser fusion, a number of intense laser beams are symmetrically radiated on a hollow plastic pellet containing a mixture of tritium and deuterium gas.

The intense laser energy implodes the pellet shell thereby compressing the gas. If the densities of the compressed gas reach the order of 1000 times that of liquid DT, extraordinary nuclear energy gain is achieved in addition to sufficient heating of the gas.

In the indirect-drive method, the pellet is centered inside an enclosure, and x-rays are produced when intense laser beams enters the enclosure and strikes the walls.

The resulting cloud of x-rays symmetrically implode the pellet shell to generate the necessary compression and heating.

Laser fusion ensures the use of high-quality raw materials, product reliability and functionality in a fully controlled environment.

In the direct laser fusion approach, no debris is left to recycle, and the materials do not cause activation problem.

Unlike nuclear fission plants, laser fusion does not produce large amounts of high-level nuclear waste which requires long-term disposal.

No active intervention, cooling, reprocessing and external power is required at the time the shutdown of a laser fusion power plant. The plant allows for periodic replacement of materials under high-risk environments without requiring changes to the rest of the plant.

It provides an essentially carbon-free energy source with a practically unlimited supply of fuel.

High-powered lasers are the key to this technique, as achieving fusion in this way needs an enormous amount of energy to be delivered as a pulse.

However, one major problem with the most advanced lasers today is that they are relatively inefficient at converting electrical energy into beam energy. In addition, not all of the laser energy ends up being delivered to the fusion target.

Some of the laser light end up being scattered or reflected away.

Laser fusion greatly benefits from its ability to use modular advancements in component technologies and enhanced fusion performance. Therefore, future designs can readily be implemented as long as they maintain the same interface characteristics to the rest of the plant.

Sources and Further Reading

Kris Walker

Written by

Kris Walker

Kris has a BA(hons) in Media & Performance from the University of Salford. Aside from overseeing the editorial and video teams, Kris can be found in far flung corners of the world capturing the story behind the science on behalf of our clients. Outside of work, Kris is finally seeing a return on 25 years of hurt supporting Manchester City.

Citations

Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Walker, Kris. (2019, May 22). What is Laser Fusion?. AZoCleantech. Retrieved on September 19, 2019 from https://www.azocleantech.com/article.aspx?ArticleID=419.

  • MLA

    Walker, Kris. "What is Laser Fusion?". AZoCleantech. 19 September 2019. <https://www.azocleantech.com/article.aspx?ArticleID=419>.

  • Chicago

    Walker, Kris. "What is Laser Fusion?". AZoCleantech. https://www.azocleantech.com/article.aspx?ArticleID=419. (accessed September 19, 2019).

  • Harvard

    Walker, Kris. 2019. What is Laser Fusion?. AZoCleantech, viewed 19 September 2019, https://www.azocleantech.com/article.aspx?ArticleID=419.

Comments

  1. Robert Steinhaus Robert Steinhaus United States says:

    Kris - I would like to complement you on your fine article and would like to offer a couple of additional insights for your readers.

    The energy delivered by the NIF laser is only moderate, but the energy is supplied in a very small amount of time. NIF as currently configured delivers about 1.8 MJ of energy in laser light to the hohlraum capsule and this is the amount of energy that could be produced by burning efficiently 0.014 gallons of gasoline
    http://www.flickr.com/photos/argonne/5351930355/

    This same 1.8 MJ of energy is about the amount of energy that NIF is designed to produce from fusion each shot. So when NIF does achieve fusion ignition of a Deuterium-Tritium plasma, you can expect to receive only about 1.8 MJ of energy each shot (the energy produced by burning 0.014 gallons of gasoline). NIF is capable of, with a maximum team effort, producing about three laser shots a day. So the amount of energy that the current NIF facility is capable of generating from fusion, once fusion ignition is achieved, is only about the energy equivalent of 0.042 gallons of gasoline a day.

    One of the recommendations that reviewers that oversee NIF for DOE have offered is that fusion targets be developed that are larger in size and produce greater energy yield.

The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of AZoCleantech.com.

Tell Us What You Think

Do you have a review, update or anything you would like to add to this article?

Leave your feedback
Submit