EXPLAINER: Why fusion could be a clean-energy breakthrough

Dec 12, 2022, 2:25 AM | Updated: Dec 15, 2022, 1:29 pm
In this 2012 image provided by Lawrence Livermore National Laboratory, a technician reviews an opti...

In this 2012 image provided by Lawrence Livermore National Laboratory, a technician reviews an optic inside the preamplifier support structure at the Lawrence Livermore National Laboratory in Livermore, Calif. The major advance in fusion research announced in Washington on Tuesday, Dec. 13, 2022, was decades in coming, with scientists for the first time able to engineer a reaction that produced more power than was used to ignite it. (Damien Jemison/Lawrence Livermore National Laboratory via AP)

(Damien Jemison/Lawrence Livermore National Laboratory via AP)

The major advance in fusion research announced in Washington on Tuesday was decades in coming, with scientists for the first time able to engineer a reaction that produced more power than was used to ignite it.

Using powerful lasers to focus enormous energy on a miniature capsule half the size of a BB, scientists at the Lawrence Livermore National Laboratory in California started a reaction that produced about 1.5 times more energy than was contained in the light used to produce it.

There are decades more to wait before fusion could one day — maybe — be used to produce electricity in the real world. But the promise of fusion is enticing. If harnessed, it could produce nearly limitless, carbon-free energy to supply humanity’s electricity needs without raising global temperatures and worsening climate change.

At the press conference in Washington, the scientists celebrated.

“So, this is pretty cool,” said Marvin “Marv” Adams, the National Nuclear Security Administration deputy administrator for defense programs.

“Fusion fuel in the capsule got squeezed, fusion reactions started. This had all happened before – 100 times before – but last week for the first time they designed this experiment so that the fusion fuel stayed hot enough, dense enough and round enough for long enough that it ignited,” said Adams. “And it produced more energy than the lasers had deposited.”

Here’s a look at exactly what nuclear fusion is, and some of the difficulties in turning it into the cheap and carbon-free energy source that scientists hope it can be.

WHAT IS NUCLEAR FUSION?

Look up, and it’s happening right above you — nuclear fusion reactions power the sun and other stars.

The reaction happens when two light nuclei merge to form a single heavier nucleus. Because the total mass of that single nucleus is less than the mass of the two original nuclei, the leftover mass is energy that is released in the process, according to the Department of Energy.

In the case of the sun, its intense heat — millions of degrees Celsius — and the pressure exerted by its gravity allow atoms that would otherwise repel each other to fuse.

Scientists have long understood how nuclear fusion has worked and have been trying to duplicate the process on Earth as far back as the 1930s. Current efforts focus on fusing a pair of hydrogen isotopes — deuterium and tritium — according to the Department of Energy, which says that particular combination releases “much more energy than most fusion reactions” and requires less heat to do so.

HOW VALUABLE COULD THIS BE?

Daniel Kammen, a professor of energy and society at the University of California at Berkeley, said nuclear fusion offers the possibility of “basically unlimited” fuel if the technology can be made commercially viable. The elements needed are available in seawater.

It’s also a process that doesn’t produce the radioactive waste of nuclear fission, Kammen said.

Crossing the line of net energy gain marks a major achievement, said Carolyn Kuranz, a University of Michigan professor and experimental plasma physicist.

“Of course, now people are thinking, well, how do we go to 10 times more or 100 times more? There’s always some next step,” Kuranz said. “But I think that’s a clear line of, yes, we have achieved ignition in the laboratory.”

HOW ARE SCIENTISTS TRYING TO DO THIS?

One way scientists have tried to recreate nuclear fusion involves what’s called a tokamak — a doughnut-shaped vacuum chamber that uses powerful magnets to turn fuel into a superheated plasma (between 150 million and 300 million degrees Celsius) where fusion may occur.

The Livermore lab uses a different technique, with researchers firing a 192-beam laser at a small capsule filled with deuterium-tritium fuel. The lab reported that an August 2021 test produced 1.35 megajoules of fusion energy — about 70% of the energy fired at the target. The lab said several subsequent experiments showed declining results, but researchers believed they had identified ways to improve the quality of the fuel capsule and the lasers’ symmetry.

WHY IS FUSION SO HARD?

It takes more than extreme heat and pressure. It also takes precision. The energy from the lasers must be applied precisely to counteract the outward force of the fusion fuel, according to Stephanie Diem, an engineering physics professor at the University of Wisconsin-Madison.

And that’s just to prove net energy gain is possible. It’s even harder to produce electricity in a power plant.

For example, the lab’s lasers can only fire a few times a day. To viably produce energy, they would need to fire rapidly and capsules would need to be inserted multiple times a minute, or even faster, Kuranz said.

Another challenge is to increase efficiency, said Jeremy Chittenden, a professor at Imperial College in London specializing in plasma physics. The lasers used at Livermore require a lot of electrical energy, and researchers need to figure out a way to reproduce their results in a much more cost-effective way, he said.

___

Associated Press reporter Maddie Burakoff contributed to this report.

___

Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

Copyright © The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

AP

FILE - Bryan Kohberger, who is accused of killing four University of Idaho students in Nov. 2022, a...
Associated Press

News groups ask Idaho Supreme Court to reject University slayer gag order

Thirty news organizations have asked the Idaho Supreme Court to overturn a gag order in a case against a man accused of stabbing four students to death.
16 hours ago
Nathan Chasing Horse stands in court. Monday, Feb. 6, 2023, in North Las Vegas, Nev. Nathan Chasing...
Associated Press

‘Dances With Wolves’ actor charged in 2018 rape in PNW

Canadian police confirmed Tuesday they are pursuing a criminal case against a former "Dances With Wolves" actor who was arrested last week and charged in Nevada with sexually abusing and trafficking Indigenous women and girls.
16 hours ago
Associated Press

Lawmakers in GOP states target medical care for trans kids

OKLAHOMA CITY (AP) — Republican attacks on gender affirming medical care for young people continued Wednesday in several conservative states that are among more than two dozen considering similar bans nationwide. Lawmakers in Nebraska, Oklahoma and South Dakota considered bills Wednesday that would prohibit gender affirming treatments, like the use of puberty-blocking drugs and hormones, […]
16 hours ago
FILE - This combination of images provided by the Memphis Police Department shows, from top row fro...
Associated Press

Jury may not hear cops’ admissions in Tyre Nichols’ beating

It was a stunning revelation: One of the officers involved in the fatal beating of Tyre Nichols took a cellphone photo of the bloodied and handcuffed man and shared it with five other people. The disclosure was part of the Memphis Police Department’s request to the state that the five former officers charged with murder […]
16 hours ago
A man takes photos as a black plume rises over East Palestine, Ohio, as a result of a controlled de...
Associated Press

Residents can return after air deemed safe from derailment

EAST PALESTINE, Ohio (AP) — Evacuated residents can safely return to the Ohio village where crews burned toxic chemicals after a train derailed five days ago near the Pennsylvania state line, East Palestine Fire Chief Keith Drabick said Wednesday. Authorities in East Palestine had warned that burning vinyl chloride that was in five of the […]
16 hours ago
FILE - The Netflix logo is shown in this photo from the company's website on Feb. 2, 2023, in New Y...
Associated Press

Netflix steps up its effort to get paid for account sharing

Netflix has a plan to deal with rampant account sharing: a program that lets subscribers pay extra to share their account with people outside their household. The streaming giant introduced paid sharing in Canada, New Zealand, Portugal and Spain on Wednesday. It was previously rolled out in multiple markets in Latin America. While Netflix won’t […]
16 hours ago

Sponsored Articles

safety from crime...

As crime increases, our safety measures must too

It's easy to be accused of fearmongering regarding crime, but Seattle residents might have good reason to be concerned for their safety.
Comcast Ready for Business Fund...
Ilona Lohrey | President and CEO, GSBA

GSBA is closing the disparity gap with Ready for Business Fund

GSBA, Comcast, and other partners are working to address disparities in access to financial resources with the Ready for Business fund.
SHIBA WA...

Medicare open enrollment is here and SHIBA can help!

The SHIBA program – part of the Office of the Insurance Commissioner – is ready to help with your Medicare open enrollment decisions.
Lake Washington Windows...

Choosing Best Windows for Your Home

Lake Washington Windows and Doors is a local window dealer offering the exclusive Leak Armor installation.
Anacortes Christmas Tree...

Come one, come all! Food, Drink, and Coastal Christmas – Anacortes has it all!

Come celebrate Anacortes’ 11th annual Bier on the Pier! Bier on the Pier takes place on October 7th and 8th and features local ciders, food trucks and live music - not to mention the beautiful views of the Guemes Channel and backdrop of downtown Anacortes.
Swedish Cyberknife Treatment...

The revolutionary treatment of Swedish CyberKnife provides better quality of life for majority of patients

There are a wide variety of treatments options available for men with prostate cancer. One of the most technologically advanced treatment options in the Pacific Northwest is Stereotactic Body Radiation Therapy using the CyberKnife platform at Swedish Medical Center.
EXPLAINER: Why fusion could be a clean-energy breakthrough