Scientists announce breakthrough in fusion energy

Scientists at a federal nuclear weapons facility have made a potentially significant advance in fusion research that could lead to an abundant source of energy in the future, according to a government official.

Details of the breakthrough are expected to be announced today by the Department of Energy, which said a “significant scientific breakthrough” has been made at California’s Lawrence Livermore National Laboratory.

Secretary of Energy Jennifer Granholm, White House and Department of Energy officials are expected to attend.

The Financial Times reported Sunday that the scientific discovery is related to the National Ignition Facility, or NIF, which it uses giant lasers to create conditions that briefly mimic the explosions of nuclear weapons.

The official, who spoke on condition of anonymity to refer to findings that are not yet public, said the fusion experiment at NIF has achieved what is known as power onwhere the fusion energy generated equals the laser energy that started the reaction.

it is also called ignition your energy gain.

A scientist familiar with the results who spoke anonymously for the same reason also confirmed that the NIF achieved ignition.

This breakthrough would improve the United States’ ability to maintain its nuclear weapons. no nuclear tests and could lay the groundwork for future advances that may one day lead to the use of laser fusion such as carbon-free energy source.

While not yet publicly announced, the news has quickly bounced around among physicists and other scientists who study fusion.

“Yesterday a scientist friend sent me a note saying that Livermore exceeded the energy gain by just one last week and would announce the result on Tuesday,” said Stephen Bodner, a retired plasma physicist who was long a critic of the NIF, in an email on Monday morning.

“They deserve praise for achieving their goal.”

What is Fusion?

Fusion is the thermonuclear reaction that powers the Sun and other stars:

the fusion of hydrogen atoms into helium.

The mass of helium is slightly less than that of the original hydrogen atoms.

Therefore, according to Einstein’s emblematic equation E=mc2, this mass difference becomes a burst of energy.

A fusion that could occur in a controlled manner on Earth could mean an energy source that does not produce greenhouse gases, such as coal and oil, or dangerous long-lived radioactive waste, such as today’s nuclear power plants.

How does merging happen without a star?

To date, most fusion projects have used donut-shaped reactors, known as tokamak.

In these reactors, the hydrogen gas becomes hot enough for electrons to detach from the hydrogen nuclei, creating what is known as plasma:

clouds of positively charged nuclei and negatively charged electrons.

Magnetic fields trap the plasma inside the donut shape and the nuclei fuse, releasing energy in the form of outward flying neutrons.

Tuesday’s announcement, however, implies a different approach.

The NIF consists of 192 giant lasers which fire simultaneously at a metal cylinder the size of a pencil eraser.

The cylinder, heated to approximately 5.4 million degrees Fahrenheit, vaporizes, generating an implosion of X-rays, which in turn heats and compresses a ball-sized pellet of frozen deuterium and tritium pellets, two heavier forms of hydrogen.

The implosion dissolves the hydrogen into helium, creating fusion.

What progress has been made in laser melting so far?

The main goal of the NIF, built at a cost of $3.5 billion, is to conduct experiments that help the United States maintain its nuclear weapons without testing nuclear explosions.

His backers also say he could pursue the merger investigation it could lead to profitable commercial power plants.

However, NIF was hardly a merger at first.

In 2014, Livermore scientists finally reported their success, but the energy produced back then was tiny:

the equivalent of what a 60-watt light bulb consumes in five minutes.

Last year, Livermore scientists reported a huge leap, a burst of energy — 10 quadrillion watts of power — equal to 70 percent of the energy of laser light incident on the hydrogen target.

But the explosion – essentially a miniature hydrogen bomb – only lasted 100 trillionths of a second.

Sunday’s Financial Times report suggests Livermore will announce that in the latest experiment, the fusion energy produced exceeded the amount of laser energy hitting the hydrogen target.

For this to happen, there had to be the fusion reaction self sustainedthat is, the stream of particles flowing outward from the hot spot in the center of the pellet heated the surrounding hydrogen atoms and caused them to fuse together.

What are the barriers to fusion energy?

An important caveat is that the claim focuses on the laser energy hitting the hydrogen target.

NIF’s lasers are extremely inefficient, meaning that only a small fraction of the energy used to power the lasers actually reaches the beams themselves.

Newer technology, such as solid-state lasers, would be more effective, but still a long way from 100% fusion; to be practical, the fusion energy output must be at least several times that of the input lasers.

Does Tuesday’s announcement mean that we will soon have cheap fusion energy?

No.

Even if scientists figure out how to generate bigger fusion explosions, there are still huge engineering hurdles.

The NIF experiments studied one explosion at a time.

A practical fusion power plant using this concept would require a machine gun rhythm of laser bursts with new hydrogen targets snapping into position for each burst.

So should the torrents of neutrons ejected from fusion reactions become electricity.

The laser complex occupies a building the size of three football fields – too big, too expensive, and too inefficient for a commercial power plant.

A manufacturing process should be developed to mass-produce the precise hydrogen targets.

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