Since 1983, scientists have used England's Joint European Torus (JET) to recreate nuclear fusion, the merging of atoms that powers the sun and other stars, in Britain. An effective nuclear fusion setup could give us immense quantities of clean energy.
Now, during the last days of its four-decade-long life, JET has set a new record for the most energy created in a single fusion reaction. JET's new record is the latest milestone in an exciting few years for fusion. With each milestone, fusion scientists inch closer — slowly, very slowly, but steadily — toward constructing a commercial fusion power plant that can plug into the grid.
Using 0.2 milligrams of fuel (about a hundred thousandth of an ounce) JET sustained high fusion power for 5 seconds and created 69 megajoules of energy. That's about enough to power an average home for maybe a few minutes. Neither of these parameters seems Earth-shattering, but they are indeed numbers for fusion scientists to celebrate.
"JET's final fusion experiment is a fitting swansong after all the groundbreaking work that has gone into the project since 1983," UK Minister for Nuclear and Networks, Andrew Bowie, said in a statement. "We are closer to fusion energy than ever before thanks to the international team of scientists and engineers in Oxfordshire."
However, while JET did set a record for raw energy, it did not set a record for yield. That's the ratio of energy produced to the energy that scientists put in to trigger fusion in the first place. JET once held that record, too, but the National Ignition Facility (NIF) in California’s Lawrence Livermore National Laboratory surpassed it in 2022.
In fact, NIF was the first fusion facility in the world to do something that JET could not do: elicit a yield of more than 1, or, in other words, create more energy than scientists put in. As of late 2023, NIF has achieved yields of close to 2.
Tempting as it is to compare the two experiments, doing so directly is difficult. NIF is an example of inertial confinement fusion (ICF). NIF's apparatus relies on blasting a fuel-stuffed capsule with lasers, creating intense X-ray cascades that compress the fuel into fusion. JET, on the other hand, is a tokamak, or a doughnut-shaped container stuffed with superheated plasma. By magnetically sculpting the plasma, a tokamak's operators can ignite fusion.
For JET, this record means that the facility can end its life on a triumphant note. Its operators have already begun the lengthy process of decommissioning the reactor. But JET's end is certainly not the end for tokamak science. JET is a testbed for the International Thermonuclear Experimental Reactor (ITER): a future reactor set to launch in 2025, with an eye of testing tokamak tech for a line of future reactors even farther in the future.
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Rahul Rao is a graduate of New York University's SHERP and a freelance science writer, regularly covering physics, space, and infrastructure. His work has appeared in Gizmodo, Popular Science, Inverse, IEEE Spectrum, and Continuum. He enjoys riding trains for fun, and he has seen every surviving episode of Doctor Who. He holds a masters degree in science writing from New York University's Science, Health and Environmental Reporting Program (SHERP) and earned a bachelors degree from Vanderbilt University, where he studied English and physics.
Yes but the energy yeld, be 1 or 2 or whatever, are calculated with Q Plasma, the ratio of energy that actually strikes the fuel versus what energy is produced by the reaction, and not with Q Total, which is all of the energy it takes to charge the magnetic field, and in this latter case a yeld of 1 won't probably ever be attained; these huge technological efforts have careers, lobbying, political and military motivations at mostReply
Yes. I tried to find the overall efficiency but this info, as usual, is missing.orsobubu said:Yes but the energy yeld, be 1 or 2 or whatever, are calculated with Q Plasma, the ratio of energy that actually strikes the fuel versus what energy is produced by the reaction, and not with Q Total, which is all of the energy it takes to charge the magnetic field,
Calling Bill. :)
The gigantic reward of clean and abundant energy still justifies the effort.orsobubu said:and in this latter case a yeld of 1 won't probably ever be attained; these huge technological efforts have careers, lobbying, political and military motivations at most
Last time they did this, the energy coming into the building was about 100 times what they produced. There is a long way to go. Me personally, I don't place much hope, the temperatures involved are simply too high. If one is after free heat, a gyrotron drilled hole to 20 miles down will do the trick anywhere on Earth. They have not done it yet, but I have more faith in it than fusion.Reply
Here is my take on fusion. They claim they need 150e6 K. I know about heat loss by radiation as I had to deal with it in my casting shop. Steffan's law says it goes by the fourth power. I can easily melt brass at 1170 K in my electric furnace, takes about an hour. But when I go to melt copper at 1356 K, it requires 6" of pink glass wool around the kiln and it takes 10 hours. Can barely do it. Fusion is 10e20 times harder than that. I predict we will see commercial fusion in the next 20 years, just as we have said for the last 50 years.Reply
I was left with the insurmountable problems of descending with mechanical drills below 40k feet, and instead reading your comment I discovered these companies, Quaise and Ga Drilling, which are truly interesting, especially because if there are possibilities we will know in a very short time! another technology that I have always followed since 2011 is cold fusion, it has received several confirmations in recent years, and in particular I am interested in the Italian-American one by Dr. Andrea Rossi (E-Cat), who is labeled a scammer everywhere, but who I contacted personally and who I still give credit to; even in his case it is a short time for confirmation. Instead, I wonder how much truth there is in the numerous, at least five I would say, "hot" fusion technologies that are almost pocket-sized if compared to the gigantic lasers and tokamaks, and which are popping up like mushrooms in recent years, promising to solve the containment problems in much shorter order. They are generally private companies, and that doesn't give me a lot of confidence at the moment.billslugg said:Here is my take on fusion. They claim they need 150e6 K. I know about heat loss by radiation as I had to deal with it in my casting shop. Steffan's law says it goes by the fourth power. I can easily melt brass at 1170 K in my electric furnace, takes about an hour. But when I go to melt copper at 1356 K, it requires 6" of pink glass wool around the kiln and it takes 10 hours. Can barely do it. Fusion is 10e20 times harder than that. I predict we will see commercial fusion in the next 20 years, just as we have said for the last 50 years.
Cold fusion is dead, hot fusion is out of reach. Thermal drilling via gyrotron is a distinct possibility, stay tuned for Quaise results maybe this year (already a year late).Reply
If one drills a 300 mm hole down 40 km, then about 12,000 tons of rock must be blown upwards by a column of argon. It must move upwards at about a meter per second in order to stay aloft. There would be 40,000 seconds worth of dust in the annulus at any one time. If the drill time is 3 months, as they claim, then about 6 tons would be in transit at any one time. An argon pressure of 1000 psi should do it, easily attainable. Argon flow must also be fast enough to cool the glass lining as it is being formed. Downhole pressure must be high enough to prevent the sides from pushing inward. All of these things are within the grasp of current technology.