Major breakthrough in pursuit of nuclear fusion unveiled by US scientists

Scientists at the Lawrence Livermore National Laboratory in California briefly ignited nuclear fusion using powerful lasers.
Scientists at the Lawrence Livermore National Laboratory in California briefly ignited nuclear fusion using powerful lasers. (Image credit: Lawrence Livermore National Laboratory)

American researchers have achieved a major breakthrough paving the way toward nuclear fusion based energy generation, but major hurdles remain.

Nuclear fusion is an energy-generating reaction that fuses simple atomic nuclei into more complex ones, such as combining atoms of hydrogen into helium. Nuclear fusion takes place in the cores of stars when vast amounts of molecular dust collapse under gravity and create immense amounts of pressure and heat in the nascent stars' cores. 

For decades, scientists have therefore been chasing nuclear fusion as a holy grail of sustainable energy generation, but have fallen short of achieving it. However, a team from the Lawrence Livermore National Laboratory (LLNL) in California may have finally made a major leap to creating energy-giving 'stars' inside reactors here on Earth. 

A team from LLNL has reportedly managed to achieve fusion ignition at the National Ignition Facility (NIF), according to a statement (opens in new tab) published Tuesday (Dec. 13). "On Dec. 5, a team at LLNL's National Ignition Facility (NIF) conducted the first controlled fusion experiment in history to reach this milestone, also known as scientific energy breakeven, meaning it produced more energy from fusion than the laser energy used to drive it," the statement reads.

Related: Physicists just rewrote a foundational rule for nuclear fusion reactors that could unleash twice the power

The experiment involved bombarding a pencil-eraser-sized pellet of fuel with 192 lasers, causing the pellet to then release more energy than the lasers blasted it with. "LLNL's experiment surpassed the fusion threshold by delivering 2.05 megajoules (MJ) of energy to the target, resulting in 3.15 MJ of fusion energy output, demonstrating for the first time a most fundamental science basis for inertial fusion energy (IFE)," LLNL's statement reads. 

Still, that doesn't mean that fusion power is within grasp, LLNL cautions. "Many advanced science and technology developments are still needed to achieve simple, affordable IFE to power homes and businesses, and [the U.S. Department of Energy] is currently restarting a broad-based, coordinated IFE program in the United States. Combined with private-sector investment, there is a lot of momentum to drive rapid progress toward fusion commercialization," the statement continues.

Even though this is only a preliminary step towards harnessing fusion power for clean energy, LLNL leaders are hailing the accomplishment as a transformative breakthrough. "Ignition is a first step, a truly monumental one that sets the stage for a transformational decade in high-energy density science and fusion research and I cannot wait to see where it takes us," said LLNL Director Dr. Kim Budil during Tuesday's press conference.

"The science and technology challenges on the path to fusion energy are daunting. But making the seemingly impossible possible is when we're at our very best," Budil added."

Such conditions lead up to the ignition of the fusion reaction, which, however, in the current experiment was sustained for only a very short period of time. During the experiment, the energy generated by the fusing atoms surpassed the amount of energy required by the lasers igniting the reaction, a milestone known as net energy gain.

Scientists at the laboratory have conducted several fusion experiments in recent years, which haven't generated the amount of power needed to claim a major breakthrough. In 2014, the team produced about as much energy as a 60-watt light bulb consumes in five minutes. Last year, they managed to reach a power output of 10 quadrillion watts of power  —  which was about 70% as much energy as consumed by the experiment.

The fact that the latest experiment produced a little more energy than it consumed means that for a brief moment, the reaction must have been able to sustain itself, using its own energy to fuse further hydrogen atoms instead of relying on the heat from the lasers. 

However, the experiment only produced 0.4MJ of net energy gain — or about as much is needed to boil a kettle of water, according to The Guardian (opens in new tab).

The breakthrough comes as the world struggles with a global energy crisis caused by Russia's war against Ukraine while also  striving to find new ways to sustainably cover its energy needs without burning fossil fuels. Fusion energy is not only free from carbon emissions but also from potentially dangerous radioactive waste, which is a dreaded byproduct of nuclear fission. 

The New York Times (opens in new tab), however, cautions that while promising, the experiment is only the very first step in a still long journey toward the practical use of nuclear fusion. Lasers efficient enough to launch and sustain nuclear fusion on an industrial scale have not yet been developed, nor has the technology needed to convert the energy released by the reaction into electricity.

The National Ignition Facility, which primarily conducts experiments that enable nuclear weapons testing without actual nuclear explosions, used a fringe method for triggering the fusion reaction.

Most attempts at igniting nuclear fusion involve special reactors known as tokamaks, which are ring-shaped devices holding hydrogen gas. The hydrogen gas inside the tokamak is heated until its electrons split from the atomic nuclei, producing plasma. 

The lasers heated up the cylinder to a temperature of about 5.4 million degrees Fahrenheit, which vaporized the cylinder, producing a burst of X-rays. These X-rays then heated up a small pellet of frozen deuterium and tritium, which are two isotopes of hydrogen. As the core of the pellet heated up, the hydrogen atoms fused into helium in the first glimmer of nuclear fusion. 

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Tereza Pultarova
Senior Writer

Tereza is a London-based science and technology journalist, aspiring fiction writer and amateur gymnast. Originally from Prague, the Czech Republic, she spent the first seven years of her career working as a reporter, script-writer and presenter for various TV programmes of the Czech Public Service Television. She later took a career break to pursue further education and added a Master's in Science from the International Space University, France, to her Bachelor's in Journalism and Master's in Cultural Anthropology from Prague's Charles University. She worked as a reporter at the Engineering and Technology magazine, freelanced for a range of publications including Live Science, Space.com, Professional Engineering, Via Satellite and Space News and served as a maternity cover science editor at the European Space Agency.

  • Jan Steinman
    So, we're now "only 20 years away," as we have been for my entire 67-year life.

    They produced enough energy to boil a kettle of water. I'll think of that tomorrow morning when I make a pot of tea.

    Don't get me wrong — it's great to reach this milestone. But we're on a race to find a new way to power our civilization before the fossil sunlight gives out. We don't have 20 more years.
    Reply
  • billslugg
    Yes, fusion is not going to bail us out of the CO2 problem. CO2 abatement is a long term program.
    - Elimination of incandescent lamps - LED revolution - nearly complete
    - Idling of coal power plants - replace with natural gas - underway in US
    - Expansion of nuclear power - underway in US - two new plants within next 12 mos.
    - Wind and solar - underway
    - Battery development to leverage intermittent solar and wind - underway
    - Hydrogen technology - just beginning
    - Fusion - decades away
    Reply
  • PaitoonW
    I hope not to use any power produced from fusion reactor in my life-time, since I am already 74 yo.
    Reply
  • Jan Steinman
    billslugg said:
    Yes, fusion is not going to bail us out of the CO2 problem. CO2 abatement is a long term program.
    - Elimination of incandescent lamps - LED revolution - nearly complete
    - Idling of coal power plants - replace with natural gas - underway in US
    - Expansion of nuclear power - underway in US - two new plants within next 12 mos.
    - Wind and solar - underway
    - Battery development to leverage intermittent solar and wind - underway
    - Hydrogen technology - just beginning
    - Fusion - decades away
    And yet, we're down on our peak fossil sunlight consumption by only a couple percent. And that would be the other direction if we hadn't given up Russia's 10%!

    Gotta do better than that, quickly!
    Reply
  • billslugg
    In 2021 the US imported an average of 186 million barrels of oil per month.
    Since March of 2022 we are averaging the importing of 192 million per month. The last month on record is Sept 2022 at 188 million. The loss of Russian oil does not seem to have affected our imports.
    The US has consistently reduced annual CO2 emissions for about the last 15 years. This mostly due to LED lighting, coal plant conversion, solar cells. And yes, we need to pick up the pace.

    U.S. Imports of Crude Oil (Thousand Barrels) (eia.gov)



    Reply
  • Unclear Engineer
    Part of the U.S. "reduction" in CO2 emissions was the off-shoring of much of our manufacturing of consumer products to China, which has been ramping up its CO2 releases for decades to make that stuff for the U.S.

    The atmosphere is a shared environment. Unless everybody participates adequately, we will all suffer the consequences.
    Reply
  • Vernon Brechin
    The report of this so called 'breakthrough' came from people who are well versed in obscuring key details because they work in the secret environment of a nuclear weapons laboratory, Lawerence Livermore National Laboratory (LLNL). Within it is the National Ignition Facility (NIF) giant laser building which has always been primarily funded to study thermonuclear weapon (H-bomb) fuel-compression and other thermonuclear weapon's dynamics. The reported experiment was actually part of that function. Material samples were placed next to the fuel capsule to test their reaction to the intense pulse of 14 Mev fusion neutrons that were generated by the reported experiment.

    The reported input energy quantity may not have been from the lasers but instead a measure of the fraction of X-rays that ended up compressing the extremely expensive, nearly perfectly spherical, hollow diamond fuel capsule. The fusion energy production lasted about 0.08 nanoseconds. Since it took about a week to prepare the shot the duty cycle of this shot, over a one-week period, would be around 0.0000000000000002. It was finally admitted by the NIF staff that the energy needed to charge up the lasers was over 100 times greater than that used as the input reference energy to the compress the the fuel capsule. During the exceedingly brief reaction about 4% of the once frozen deuterium/tritium (D/T) fuel mixture actually 'burned' with the remaining ending up as radioactive waste coating the interior of the vacuum vessel that required cleaning out before another experiment could be performed.

    The lab employs their own definition of 'ignition' that is different than most people idea of ignition. Most people equate it with something like a match head striking a rough surface where the initial reaction spreads to the rest of the fuel in about two seconds. In the NIF inertial confinement experiment (ICF) the extremely compressed core of the fuel pellet, which was in the form of a 150 million kelvin plasma, started the fusion reaction then blew off the other 96% of the fuel before it could participate in the reaction. The fusion reaction is totally dependent upon the energy contained within the laser beams and the compressing X-rays that are generated from those beams. During the blast from the laser beams the entire expensive target assembly turns into an intensely hot plasma.

    The multibillion dollar National Ignition Facility (NIF) lasers achieved full power in 2009 and the experimenters were expected to achieve its namesake goal of 'ignition' by 2012. It failed by a wide margin but the funding kept flowing from the U.S. nuclear weapons program budget.

    I've followed the fusion energy experiments since the early 1970s with its usual claims that a practical fusion power reactor will likely only be 20-30 years away, touted by the experimenters and their fans. They often state that the power source is virtually unlimited since the fuel can be obtained from seawater. The fact is that tritium is extremely rare, extremely expensive and radioactive, having a half-life of about 12 years. There are enormous problems needed to be overcome for future fusion reactors to breed their own tritium fuel from a lithium isotope. The intense energy 14 Mev neutrons, generated by the fusion reactions, will degrade the structures around them and will render some of their atoms radioactive via the process of neutron activation reactions. The usual claims of fusion producing clean energy without creating radioactive waste is pure deceptive sales hype. Most nuclear fusion physicists agree that Magnetic Confinement Fusion (MCF) experimental approaches are far more likely to lead to a practical fusion power plant design. Still that is likely to take well over a single decade. Scaling that up to displace our addiction to fossil fuel based energy resources will take more decades. Those people, who continue to believe that nuclear power will save us, have to be masterful at excluding the following warnings from their consciousness.

    IPCC report: ‘now or never’ if world is to stave off climate disaster
    https://www.theguardian.com/environment/2022/apr/04/ipcc-report-now-or-never-if-world-stave-off-climate-disaster
    UN chief: World has less than 2 years to avoid 'runaway climate change'
    https://thehill.com/policy/energy-environment/406291-un-chief-the-world-has-less-than-2-years-to-avoid-runaway-climate * This statement was made 4-years ago.

    Here is another critical review of the recent experiment. When most journalists look for critical balance in their articles, on topics such as this, they tend to defer to those experts who have vested interest in the technology, or have long been fans of it.

    Is This the ‘Kitty Hawk Moment’ for Fusion Energy?
    https://www.theatlantic.com/technology/archive/2022/12/department-of-energy-nuclear-fusion-breakthrough-nif-livermore/672439
    Reply
  • Unclear Engineer
    Vernon Brechin said:
    Those people, who continue to believe that nuclear power will save us, have to be masterful at excluding the following warnings from their consciousness.

    While I fully agree with the post with respect to nuclear fusion, this particular statement is over-broad in that it seems to include nuclear fission as well.

    Nuclear fission power has been used for decades to power Navy ships and the commercial electric energy grid in many countries. While it is despised by some anti-nuclear activists. others are coming around to thinking we are going to have to use it to get our CO2 emissions down and keep a reasonable standard of living at the same time. It is a proven technology, not like fusion.
    Reply
  • Vernon Brechin
    Unclear Engineer said:
    While I fully agree with the post with respect to nuclear fusion, this particular statement is over-broad in that it seems to include nuclear fission as well.

    Nuclear fission power has been used for decades to power Navy ships and the commercial electric energy grid in many countries. While it is despised by some anti-nuclear activists. others are coming around to thinking we are going to have to use it to get our CO2 emissions down and keep a reasonable standard of living at the same time. It is a proven technology, not like fusion.

    I did intend to apply my comment to all forms of nuclear fision energy production. I started following it in the mid-1950s when I was just 10 years old. I was an enthusiastic fan then but allowed myself to understand the deceptions as well. As it turned out nuclear power in the U.S. never grew at the rapid rate it was expected to in the 1970s. Three major accidents later those were not foreseen either. Nor was the failed promise, from the 1950s to construct a deep geological repository for the greater than 70 metric tones of high level radioactive waste discharged from civilian and military power plant reactors. Fans get into the habit of dismissing such downsides. They often claim that the history has no bearing upon what we can achieve in the very near future.

    Please read the two warning articles from the IPCC and ask yourself how many people have the stomach to accept such a extremely short timeline to turn things around with nuclear power plant construction times, often lasting for over a decade.
    Reply
  • Unclear Engineer
    You do sound like one of the anti-nuclear activists. Nuclear power failed to take off as advertised mainly due to public political pressure resulting from nuclear reactor accidents.

    Another problem was that few plants were made to any particular design, and were largely constructed on-site. It was not pursued in the most cost-effective manner.

    And the lack of a waste repository is mainly due to public opposition.

    The newer fission reactor designs are intended to be constructed at centralized facilities and have less demanding operating parameters. There are many competing designs, some of which were previously tried and abandoned, while others are direct evolutions of the existing light water reactor technologies with familiar behaviors. We will just have to see how that works out.

    But, if the public decides that is what they want to do, the technology is already developed to do it. That is what is different about it, compared to the idea of using nuclear fusion power.

    So, while your personal opinion is that we should not use either, the truth is that one technology is available if we decide to use it while the other is not available and will not become available on a predictable schedule.
    Reply