The Rhetoric: <<The U.S. Department of Energy announced Tuesday a monumental milestone in nuclear fusion research: a "net energy gain" was achieved for the first time in history by scientists from the Lawrence Livermore National Laboratory in California.
"Simply put, this is one of the most impressive scientific feats of the 21st century," Jennifer Granholm, U.S. energy secretary, said at a press conference, adding that researchers have been working on this for decades.>> (Excerpted from: < https://www.cbsnews.com/amp/news/nuclear-fusion-energy-breakthrough-announcement/ >.) The Science: <<The facility used its set of 192 lasers to deliver 2.05 megajoules of energy onto a pea-sized gold cylinder containing a frozen pellet of the hydrogen isotopes deuterium and tritium. The pulse of energy caused the capsule to collapse, creating temperatures only seen in stars and thermonuclear weapons, and the hydrogen isotopes fused into helium, releasing additional energy and creating a cascade of fusion reactions. The laboratory’s analysis suggests that some 3.15 megajoules of energy was released—roughly 54% more than the energy that went into the reaction and more than double the previous record of 1.3 megajoules. “Fusion research has been going on since the early 50s, and this is the first time in the laboratory that fusion has ever produced more energy than it consumed,” says Campbell. The experiment safely qualifies as ignition, a benchmark measure for fusion reactions that focuses on how much energy went into the target compared to how much energy was released. However, while the fusion reactions may have produced more than 3 megajoules of energy—more than was delivered to the target—NIF’s 192 lasers consumed 322 megajoules of energy in the process. ... “Although positive news, this result is still a long way from the actual energy gain required for the production of electricity,” said Tony Roulstone, a nuclear-energy researcher at the University of Cambridge, UK, in a statement to the Science Media Centre.>> (Excerpted from: < https://www.scientificamerican.com/article/nuclear-fusion-lab-achieves-ignition-what-does-it-mean/ >.) Nuclear physicist and author M V Ramana further explicates: <<The “breakthrough” that NIF [National Ignition Facility] is talking about pertains to what I would term "physics challenges". Of these, there are three stages of challenges. The first challenge is to have enough fusion reactions in the target (the pellet or the confined gas) to produce more energy than is put into the target. The second challenge is to produce more energy than is used by the facility as a whole. So that includes all the energy that goes into running the magnets and other equipment and so on rather than just the amount fed into the target. The final material challenge would be to put in all the equipment needed to convert the heat that is produced by the fusion reactions into electricity and make that produce more electricity than is fed into the system. If these physics challenges are not met, of course, then one has a permanent loss-making facility in energy terms. As of now, NIF is far from meeting all these challenges [listed above]. Let’s assume that all of these are solved. Then there is an "engineering challenge": how do you convert this experimental set up that produces energy for a microscopic fraction of second into a continuous source of electricity that operates 24 hours/day X 365 days/year. That is far from certain. After all these are solved, then there is an even more difficult challenge - to make all of this economically competitive. I don’t think there are any reliable cost estimates for these technologies—or to put it differently, at this early stage in the game, any cost estimates are bound to be unreliable. If one goes by history, the last could be a killer as has been the case with fission power.>> Hence, the gist: I. The attempts to produce usable and useful energy out of nuclear fusion -- as distinct from fission -- is at the moment going on, for years and years, mainly in two labs run by: (i) ITER -- a collaborative project of 35 nations located in southern France -- and (ii) the National Ignition Facility (NIF), a US national project. II. The NIF/US has now announced a major breakthrough. III. The actual breakthrough is that 2.05 megajoules of energy input has produced 3.15 megajoules of energy output -- roughly 54% more than the energy that went into the reaction and more than double the previous record of 1.3 megajoules. However, the total energy consumed in the process is 322 megajoules. IV. So, let alone the final "engineering challenge", as flagged by Ramana, even meeting the three-stage "physics challenge" still remains a long long distance away. V. Hence, while it's an important achievement no doubt, the drumbeatings are not exactly warranted. -- You received this message because you are subscribed to the Google Groups "Green Youth Movement" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/greenyouth/CACEsOZgESg9Zh7pHnvz-Pcb1hYghOjc6nckpVbkUzNB0qZnhFg%40mail.gmail.com.
