The latest news, for the first time in the United States, a laboratory uses a laser beam, diamonds, and ** to achieve triple repeated ignition.To date, researchers in the United States have produced four brief bursts of fusion energy, which are encouraging signs of making this zero-carbon energy source a reality.
Lawrence Livermore National Ignition technicians are adjusting the optics within the preamplifier support structure. Damian Jamieson Lawrence Livermore National Laboratory.
For the first time, scientists have successfully performed repetitive ignition of nuclear fusion, which is another important milestone in achieving near-unlimited clean energy on a large scale.
A team at Lawrence Livermore National Laboratory (LLNL) in the United States achieved fusion ignition last December, producing a net energy gain from a fusion reaction for the first time.
This feat has been hailed by physicists as a "historic moment". Now, scientists at Lawrence National Laboratory have repeated the experiment three more times.
The laboratory uses the National Ignition Facility (NIF) to fire 192 laser beams at frozen isotope particles suspended in a diamond capsule in a gold cylinder.
The resulting reaction, which replicates the same natural processes as inside the Sun, and leads to a record level of 89% increase in energy. According to the scientific journal Nature, this is only enough energy to boil a kettle, but expanding this proof of concept could herald a "new era" in energy.
I feel good," Richard Town, head of the inertial confinement fusion science program at Lawrence National Laboratory, told the magazine, "and I think we should all be proud of this achievement." ”
Earlier this month, nuclear fusion was on the agenda of the United Nations Climate Change Conference (COP28), and countries** agreed to accelerate efforts to develop the technology.
We are getting closer and closer to a fusion-driven reality. At the same time, there are significant scientific and engineering challenges," US climate envoy John Kerry said at the Dubai summit, "and careful thinking and thoughtful policies are essential to address this issue." ”
China, Japan, Russia and the European Union have also invested heavily in fusion research, with more than $6 billion invested so far, according to the Fusion Industry Association.
One of the companies investing in the technology is US tech giant Microsoft, which announced the world's first purchase agreement earlier this year.
But what exactly do these experiments mean for science and the dream of a new energy source that powers our homes and cars without emitting any carbon dioxide?
In short, it's okay to applaud NIF's accomplishments, but that doesn't mean the green energy revolution is coming. Progress in fusion power generation will take years to come to fruition – it could take a decade or so – and it's unclear whether fusion power is cheap enough to fundamentally change our grid. There is no doubt that continuing to invest more in solar and wind energy today is essential to combat climate change.
Fusion occurs when two lighter elements, such as hydrogen or helium, merge into one heavier element. This nuclear reaction releases a lot of energy, as demonstrated by the largest fusion furnace around the sun.
However, fusion is more difficult to occur on Earth because the nuclei are positively charged and therefore mutually repellent. The huge mass of the Sun creates tremendous pressure to overcome this repulsive force, but on Earth, other forces are needed.
The two common methods of squeezing atoms together and creating fusion are called inertial and magnetic confinement. Inertial confinement typically uses a laser to hit a projectile with powerful energy, triggering the compression of fusion fuel. That's how NIFs are used.
Another method uses magnetic fields. This phenomenon is more prevalent among companies trying to commercialize fusion energy.
In December 2022, the NIF experiment crossed the critical threshold for fusion, and the energy produced by the fusion reaction (3.15 million joules) exceeded that produced by the laser that initiated the reaction205 megajoules of energy. However, since more energy is required to run the laser, the efficiency of the entire reaction is very low.
Fusion researchers used the letter q to denote the ratio of output energy to input energy, and the December 2022 reaction was the first time that a fusion reaction exceeded q = 1. On July 20, October 8 and October 30 of this year, the NIF repeated its success in that q was greater than 1. In the experiment on October 30, a record laser power was used, i.e. 22 megajoules, this improvement is very difficult because the laser destroys the optical device that directs its light.
Bruno van Wongerhem, head of operations at NIF, said in a statement: "It's all about controlling the damage. Without proper protection, too much energy and your optics will be blown to pieces. ”
Before it can be practical to generate electricity, fusion reactors must reach a threshold of q=10. This is the goal of every participant, including another large-scale project funded by the French Thermonuclear Experimental Reactor (ITER). Fusion reactors must reach q = 10 more often than NIF.
In some ways, these are academic milestones that have been fueled by fusion experiments for decades. But considering that nuclear fusion is known for not being able to achieve this. It is an important proof that anything is possible. Before you repeat that oft-quoted vitriolic statement, think carefully about the fact that fusion is the energy of the future and always will be.
On the one hand, most commercial fusion energy projects use various forms of magnetic confinement rather than NIF's laser-based approach, so the difficulty of the engineering challenge varies.
NIF, on the other hand, is a sprawling $3.5 billion national laboratory project, a project to study nuclear power, not one that aims to produce reliable energy for the grid at the most competitive cost.
Wilson Ricks, a researcher at Princeton University, said in an article published on X (formerly Twitter): "Don't expect the fusion plant of the future to be like NIF. "NIF's lasers and the extremely inefficient conversion of fusion heat into electrical energy mean that their design is inherently impractical. In contrast, "magnetic confinement fusion has some real promise," Rix wrote on Twitter.
Reducing the cost of fusion is critical to its success, as it must compete with zero-carbon alternatives, such as today's fission nuclear reactors, which can generate stable electricity**, as well as cheaper but intermittent renewable energy sources such as wind and solar.
Researchers at the Princeton Plasma Physics Laboratory concluded in a study published in October: "The first competitor to nuclear fusion is fission. "This assesses the prospects of nuclear fusion in the power grid and has not been peer-reviewed. They expect that if the high cost of fusion can be low enough, it could replace future demand for fission plants, and if it is further reduced, it could also compete with a combination of solar and energy storage.
If fusion power plants can be built into cheaper, smaller units, more like what is produced in a factory, then the cost of production should be lower. This is thanks to a phenomenon called Wright's law (experience curve or learning curve), which steadily reduces the cost of solar and wind energy. The larger and more customized the fusion plant, the smaller the cost reduction and the less competitive the fusion will be.
Andrew Holland, chief executive of the Fusion Industry Association, an advocacy group for the industry, said scientists could benefit from NIF experiments by updating the physical model of fusion to account for the fact that it provides heat on its own rather than relying on external heat.
This focus may also help, especially given the long-standing skepticism about fusion energy.
Michl Binderbauer, CEO of TAE Technologies, called the NIF results "a huge stepping stone to the dawn of the fusion era" and said it was an important example of how fusion energy is indeed possible.
Investors have also taken notice. Holland said the volume of the Fusion Industry Association's annual report, which details $4.8 billion in venture capital investment in fusion energy start-ups, increased tenfold after the first NIF results were announced. He added that many of the people who made the request came from investment firms.
NIF uses 192 powerful infrared lasers to trigger nuclear fusion, with a total energy level of 4 megajoules, which is roughly equivalent to a two-ton truck traveling at 100 mph. It is first converted into 2 megajoules of ultraviolet light, which is then converted into X-rays that irradiate the fusion fuel particles the size of peppercorns.
The intense X-rays cause the outer layer of the particle to be **sexual**, compressing the inside of the particle and triggering fusion. The heat produced by fusion sustains the reaction until the fuel runs out or becomes unbalanced and shaky.
Lawrence Livermore National Laboratory's national ignition unit is the size of three football fields.
Absolutely!Here's a quick recap.
Everything on Earth is made up of tiny atoms, each of which consists of a central nucleus and a cloud of negatively charged electrons. The nucleus is made up of neutrons and positively charged protons. The more protons there are in the nucleus, the heavier the element.
Hydrogen, which usually has one proton and one electron. An unusual variety called deuterium also has a neutron, and using a nuclear reactor or fusion reactor, you can make a third element called tritium with two neutrons.
When these positive and electric charges cause atoms to interact, chemical reactions occur, such as iron rusting or wood burning. In contrast, a nuclear reaction occurs when atomic nuclei** or are combined. On Earth, it is more difficult to mobilize the forces necessary for a nuclear reaction to occur, which is why it is easier to make a steam engine than a nuclear bomb.
When you heat the atoms high enough, they become so full of energy that the electrons are stripped away. The resulting negatively charged electrons and positively charged nucleus clouds are known as plasma, a more peculiar state of matter than the solids, liquids, and gases we are accustomed to at room temperature on Earth.
The sun is made of plasma, and fusion reactors also need it to make the hydrogen nuclei bounce with enough energy. A convenient property of plasmas is that their charged particles can be manipulated with magnetic fields. This is critical for many fusion reactor designs.
NIF and most other fusion projects use two types of heavy hydrogen: deuterium and tritium, known as DT fuels. But there are other options, including hydroboron and deuterium helium-3, a form of helium with only one neutron instead of the more common two.
In order for deuterium and tritium to fuse, the plasma needs to be heated to about 100 million degrees Celsius (1800 million degrees Fahrenheit). Other reactions are even higher, such as hydrogen-boron fusion, which has a temperature of about one billion degrees.
Deuterium can be filtered out of ordinary water, but tritium is hard to come by, and it decays radioactively within a few years. It can be made in a nuclear reactor and, in principle, in a future fusion reactor. However, managing tritium is complex because it is used to promote nuclear *** and therefore needs to be tightly controlled.
The deuterium-tritium fusion reaction produces fast-moving individual neutrons. Their kinetic energy can be captured by a liquid "blanket" around the fusion reactor chamber and heated up when neutrons collide.
The heat is then transferred to the boiling water and powered by a conventional steam turbine. This technology is well known, but no one has yet connected it to a fusion reactor. In fact, the first generation of fusion power reactors being built today were designed to exceed q=1, but not to capture energy. This will await the pilot plant that is expected to arrive in the next wave of development.
Both. The NIF is funded by the nuclear program of the United States。U.S.** funding also funds the UK's Union Europa and France's International Thermonuclear Experimental Reactor, both of which are more aligned with the goal of generating electricity from fusion energy.
But more and more fusion energy is privately funded. According to the Fusion Industry Association's annual report released in early 2022, investors have poured a total of $4.8 billion into fusion energy startups, of which $2.8 billion was invested in the last year. Much of it went to Commonwealth Fusion Systems, a start-up spun off from MIT. and raised more than $1.8 billion in a funding round in 2021.
* Now also helping the private sector. The U.S. Department of Energy announced a milestone program in September 2022 to provide up to $50 million for the construction of a fusion energy pilot plant. Biden**, a supporter of nuclear fusion, said in November 2022Fusion energy is one of five key ways to halve carbon emissions by 2030 and reach net-zero emissions by 2050.
Fission, which powers today's nuclear reactors, is the opposite of fusion. In fission, heavy elements like uranium become lighter elements and release energy in the process.
For decades, humans have been able to achieve fusion using thermonuclear **. These designs smash materials such as uranium or plutonium together to initiate fission** and provide the enormous energy needed to initiate secondary and more powerful fusion reactions.
In bombs, this process takes place in less than a second, but in order to produce energy, fusion must be controlled and sustained.
Yes, in general, but it's not as cumbersome as a fission reactor. On the one hand, most radioactive emitters are short-lived alpha particles (helium nuclei with a pair of protons and a pair of neutrons) that are easily blocked. Fast-moving neutrons can collide with other materials and produce other radioactive materials.
The neutron output of fusion reactors often degrades the performance of components and requires regular replacement, which can require downtime lasting months every few years. However, it is easier to dispose of than high-level radioactive nuclear waste from fission power plants.
Hydrogen-boron fusion is less achievable than deuterium-tritium fusion, but part of its appeal is that it does not produce any neutrons and accompanying radioactive material. The most well-known company that has adopted this approach is TAE Technologies.