Fusion Breakthrough? Big, if True
December 11, 2022
Nuclear fusion has been, so the joke goes, 10 years away for the last 50 years.
Now reports circulating of a breakthrough.
Don’t get your hopes up, even if this is everything we would hope, it’s a long, long way from a proof of concept to a working generator – a decade? or decades?
US government scientists have made a breakthrough in the pursuit of limitless, zero-carbon power by achieving a net energy gain in a fusion reaction for the first time, according to three people with knowledge of preliminary results from a recent experiment. Physicists have since the 1950s sought to harness the fusion reaction that powers the sun, but no group had been able to produce more energy from the reaction than it consumes — a milestone known as net energy gain or target gain, which would help prove the process could provide a reliable, abundant alternative to fossil fuels and conventional nuclear energy.
The federal Lawrence Livermore National Laboratory in California, which uses a process called inertial confinement fusion that involves bombarding a tiny pellet of hydrogen plasma with the world’s biggest laser, had achieved net energy gain in a fusion experiment in the past two weeks, the people said. Although many scientists believe fusion power stations are still decades away, the technology’s potential is hard to ignore. Fusion reactions emit no carbon, produce no long-lived radioactive waste and a small cup of the hydrogen fuel could theoretically power a house for hundreds of years.
The US breakthrough comes as the world wrestles with high energy prices and the need to rapidly move away from burning fossil fuels to stop average global temperatures reaching dangerous levels. Through the Inflation Reduction Act, the Biden administration is ploughing almost $370bn into new subsidies for low-carbon energy in an effort to slash emissions and win a global race for next-generation clean tech.
Recipe for a Small Star
- Take a hollow, spherical plastic capsule about two millimeters in diameter (about the size of a small pea)
- Fill it with 150 micrograms (less than one-millionth of a pound) of a mixture of deuterium and tritium, the two heavy isotopes of hydrogen.
- Take a laser that for about 20 billionths of a second can generate 500 trillion watts—the equivalent of five million million 100-watt light bulbs.
- Focus all that laser power onto the surface of the capsule.
- Wait ten billionths of a second.
- Result: one miniature star.
December 11, 2022 at 7:32 pm
And how just much energy was expended getting the deuterium and tritium?
But yes an important step.
December 12, 2022 at 6:41 pm
I think you might not be remembering the “joke” about fusion correctly. The title of your March 7, 2022 post was “Fusion: After 50 Years, Still 30 Years Away?” 30 years – not 10 years.
I am surprised and disappointed by the tweet from Dr. Leah Stokes. I had thought that she is well-informed and discerning. But, her tweet indicates that she has accepted the hype around the new fusion “breakthrough.” Sad… This damages her credibility.
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December 12, 2022 at 6:45 pm
Some people look at climate change and panic. And they should panic – climate change is probably the biggest problem humans have ever faced. However, too many people then lose their minds and don’t think clearly. They hear that energy from solar and wind is no good because sometimes the sun doesn’t shine and the wind doesn’t blow. They see the hype about small modular nuclear reactors and think, “There’s the solution!” For 50 years, the nuclear industry has been unable to solve the problem of storing intensely radioactive nuclear waste for thousands of years. Somehow they believe the promises that human ingenuity will soon solve this radioactive waste problem. But, they doubt that humans can figure out how to store solar/wind electricity overnight. It is the logic of people who are panicking and not thinking clearly.
(Awhile ago a friend posted some comments that indicated he was falling for the hype around small modular nuclear reactors. I worked on writing a response to that, but I decided it just wasn’t worth the effort and gave up on it. Perhaps I should pull that out and finish it.)
And now we have fusion and the hype that this is going to save us. The WaPo article tells us this will provide “unlimited, cheap, clean power.” It’s the “holy grail” of carbon-free power. It will “bring electricity to the grid with no carbon footprint, no radioactive waste and far fewer resources than it takes to harness solar and wind power.” I suspect these claims are vastly exaggerated.
Of course the fusion breakthrough hype is a bit vague, but it sounds like they are going to claim they produced more energy out than the energy put in. Rather than listening to the hype as reported by the news media, I would suggest looking at some commentary from people who actually know what they are talking about. This will give some perspective to evaluate the big breakthrough announcement. You might start with this:
How close is nuclear fusion power?
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December 12, 2022 at 6:49 pm
Here’s another perspective that was published in the Bulletin of the Atomic Scientists. Excerpt:
“As we move closer to our goal, however, it is time to ask: Is fusion really a “perfect” energy source? After having worked on nuclear fusion experiments for 25 years at the Princeton Plasma Physics Lab, I began to look at the fusion enterprise more dispassionately in my retirement. I concluded that a fusion reactor would be far from perfect, and in some ways close to the opposite.”
Fusion reactors: Not what they’re cracked up to be
https://thebulletin.org/2017/04/fusion-reactors-not-what-theyre-cracked-up-to-be/
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December 12, 2022 at 6:50 pm
Here is another article about fusion energy…
ITER is a showcase … for the drawbacks of fusion energy
https://thebulletin.org/2018/02/iter-is-a-showcase-for-the-drawbacks-of-fusion-energy/
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December 14, 2022 at 1:49 am
This event, and the news of it on TV is apparently 99% hype.
See:
https://www.washingtonpost.com/business/2022/12/13/fusion-energy-biden-climate/
According to the above article, the experiment produced scientific break even by using 2 megajoules of laser energy to explode a D-T particle, which produced 3 megajoules of fusion energy. That sounds pretty good, right? Unfortunately, according to the above article, 300 megajoules of “wall plug” energy (power supplies) was required to produce the laser energy. If that is true, then they got only 1% return on the total energy expended.
Even if I am wrong or the laser efficiency issue could be resolved, there would be a huge problem scaling this experiment up to commercial power production, which requires one such explosion per second, according to the article.
It’s my understanding that the mission of the National Ignition Facility is only to understand the physics of nuclear weapons, not to produce power. If you want power, then I think the best path forward is magnetic confinement, i. e., tokamaks, as are being developed in the ITER program.