Source: The target chamber of LLNL’s National Ignition Facility, where 192 laser beams delivered more than 2 million joules of ultraviolet energy to a tiny fuel pellet to create fusion ignition. Lawrence Livermore National Laboratory.

Preface. Anyone who thought the recent headlines about a “Nuclear Fusion Breakthrough” were true, might be surprised to know that most media left out one or more of the following important information:

• That the purpose of the Lawrence Livermore National Laboratory (LLNL) National Ignition Facility (NIF) is to test nuclear bombs to be sure they’ll explode and make better nuclear weapons in the future
• There is no goal of generating electricity from fusion, only testing weapons at LLNL
• That 100 times more energy was used to charge the lasers (300 MJ) than came out
• The huge size of the facility required — three football fields containing 192 lasers to blast a sphere the size of a peppercorn that needs to be made of diamond and perfectly round and blasted at exactly the same time from all lasers
• A power plant based on this method would need to make 10 shots per second on one million capsules a day that are made, filled, positioned, blasted, and cleared away (Clery 2022)
• That attempts usually fail because the peppercorn sphere must be absolutely perfect plus the lasers must all fire together within 25 trillionths of a second
• That most tests fail because of the perfection required
• Each capsule costs hundreds of thousands of dollars paid for with $349 million a year of government money, $3.5 billion since 2010 (Hunt 2022).
• It takes a day for the lasers to cool down after a single shot, but fusion electricity would require the lasers to fire 10 times a second

The media forgot to say that the $3.5 billion dollar NIF at LLNL created in 2010 exists to test nuclear and teach the next generation of nuclear weapon engineers how to make better bombs in the future.  This is done by setting out various steel alloys and other components to see how they might fare in an actual nuclear explosion replicated by these fusion blasts (Mecklin 2022).

It’s certainly an improvement over the past. Before the NIF, a random nuclear bomb was taken out of the arsenal and exploded underground to make sure it was still as destructive. If less than expected, in a future nuclear war more bombs would be dropped to compensate.

Today, 192 lasers taking up three football fields blast a sphere the size of a peppercorn to 50 million degrees Centigrade at 150 billion times the pressure of Earth’s atmosphere. Each of the 192 lasers must bombard the sphere at exactly the same time with perfect symmetry on all sides. If there is any lack of symmetry, even as  the peppercorn is squeezed like a balloon, which creates escape holes for the hydrogen and no fusion, and that’s what usually happens (LLNL 2021). The sphere must be absolutely perfect.

In 2021 there was a somewhat successful attempt, but at least four others that failed, and there are likely to be terrifically expensive failures in the future — each capsule costs hundreds of thousands of dollars and several months to create. If there’s an imperfection even the size of a single bacterium it can fail.  On top of that, laser-alignment discrepancies on the order of trillionths of a meter and time discrepancies of 25 trillionths of a second can make the fusion attempt fail.  Whether it works or not, the lasers are so powerful they damage their own guiding optics every time they fire and have to be repaired (Genkina 2022).

The miniscule 1.10 MJ of energy out from the 300 MJ in is enough to boil about 10 kettles of water according to Jeremy Chittenden, co-director of the Centre for Inertial Fusion Studies at Imperial College in London.

Compare that to oil: in the beginning with the energy in one barrel of oil you could get 100 more barrels.

It appears that LLNL Fusion EROI is America’s Biggest Loser.  Makes cellulosic ethanol look good, which uses at least five times more energy to create than is delivered — that’s why it still isn’t commercial, every cellulosic plant that’s tried to create it has gone out of business.

No wonder many researchers doubt that laser-driven fusion will be the approach that ultimately yields fusion energy (Tollefson J et al 2022).

Alice Friedemann  www.energyskeptic.com  Author of Life After Fossil Fuels: A Reality Check on Alternative Energy; When Trucks Stop Running: Energy and the Future of Transportation”, Barriers to Making Algal Biofuels, & “Crunch! Whole Grain Artisan Chips and Crackers”.  Women in ecology  Podcasts: WGBH, Financial Sense, Jore, Planet: Critical, Crazy Town, Collapse Chronicles, Derrick Jensen, Practical Prepping, Kunstler 253 &278, Peak Prosperity,  Index of best energyskeptic posts

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2022 Fusion Breakthroughs in Context: Professors Holdren and Bunn Reflect on Fusion Ignition Announcement

Holdren served as President Obama’s Science Advisor and Director of the White House Office of Science and Technology Policy from 2009 – 2017. A plasma physicist who worked in the Magnetic Fusion Energy Division of the Livermore Lab in 1970-72 and served as a consultant on both magnetic and inertial confinement fusion to that Lab and the Department of Energy from 1974 to 1994, Holdren led the study of the future of the U.S. fusion-energy program produced by President Clinton’s Council of Advisors on Science and Technology in 1995.

Holdren: “The Livermore breakthrough used the world’s most powerful laser, bigger than three football fields, to create a single micro-explosion that, for the first time anywhere, yielded a bit more fusion energy than the laser energy arriving at the target. That fusion yield, however, was about 250 times smaller than the amount of electrical energy supplied to the laser for the “shot”. A practical fusion reactor based on this approach would need 10-20 times more fusion yield per shot than the electricity supplied to the laser, hence 2500-5000 times the yield of the Livermore experiment, and it would need to operate at rate of about 10 shots per second. The current Livermore device can manage 2 shots per day.

Thus, while the Livermore result represents real progress, it is miles short of the performance needed for a practical fusion reactor. The daunting energy gap just mentioned, moreover, takes no account of other, as yet unsolved problems relating to structural damage by fusion neutrons, efficient and secure breeding and recycling of the radioactive tritium needed for an adequate reaction rate, and more. The current Livermore laser-fusion system, however, is quite useful for the less-advertised, national-defense function that has paid most of the facility’s bills: studying the physics of thermonuclear explosions without blowing up real bombs.

the additional hurdles that need to be surmounted in order to arrive at a practical magnetic-fusion reactor are formidable. It seems very unlikely that fusion reactors of any type will be contributing significant electricity to the power grid before the second half of this century; and, even on that timescale, it is not obvious that they can be made both reliable and inexpensive enough to compete with other options.”

Bunn: “On the energy side, this fiendishly complex multi-billion-dollar experimental facility is a long, long way from anything a utility might buy to generate power. Some startup companies hope to achieve it much faster (with very different approaches to achieving fusion from those used at NIF), but the engineering challenges in the path of building cheap, reliable fusion power plants are huge.”

2014 The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory uses lasers to fuse hydrogen atoms together.

A physicist working on the project, Denise Hinkel, said of a 2014 test that “we’re so far away from fusion it may not be a useful way to talk about what’s happening here at Livermore”.

The goal of the NIF is to achieve “ignition”. That means that the fused hydrogen atoms need to generate as much energy as was used to run the lasers that bombarded them with heat and pressure.

According to Mark Herrmann, at Sandia National Laboratory, the pressures achieved in the 2014 test were “1,000 times lower” than needed to meet the criteria for ignition. Or less:  actually, according to the June 2014 issue of Scientific American, it was a hell of a lot less than that (Biello):

• 17,000 joules of energy were yielded by the fuel pellet
• 500,000,000,000,000 joules (500 trillion joules) were required just to feed the lasers alone
• the pellet needs to yield 29.4 million more times energy to reach ignition.  Not 1,000.
• Or if you look at it another way, that’s .0000000034% (17,000/500,000,000,000,000 = .000000000034 )
• Biello concludes “A source of nearly unlimited, clean energy is still decades away”.

When you consider what it would take to reach ignition, you will understand why many physicists don’t think NIF will ever work and is a total waste of money:

To reach ignition, 192 lasers in an area the size of 3 football fields will need to heat a tiny ball of hydrogen gas the size of a peppercorn to 50 million degrees Centigrade at 150 billion times the pressure of Earth’s atmosphere. Each of the 192 lasers must bombard the peppercorn at exactly the same time with perfect symmetry on all sides.  If there is any lack of symmetry, the peppercorn will be squeezed like a balloon, which creates escape holes for the hydrogen and no fusion.

To get to ignition scientists would need create a source of energy greater than all the energy pumped into the system by the facility’s 192 high-powered lasers – a goal some scientists say may be unachievable.

And if somehow NIF succeeded, practical fusion would still likely be decades away. NIF, at its quickest, fires once every few hours. The targets take weeks to build with artisan precision. A commercial laser fusion power plant would probably have to vaporize fuel pellets at a rate of 10 per second (Chang).

“You want to look at the big lie in each program,” says Edward C. Morse, a professor of nuclear engineering at the University of California, Berkeley. “The big lie in [laser-based] fusion is that we can make these target capsules for a nickel a piece.” The target capsules, the peppercorn-size balls of deuterium-tritium fuel, have to be exquisitely machined and precisely round to ensure that they compress evenly from all sides. Any bump on the pellet and the target won’t blow, which makes current iterations of the pellets prohibitively expensive. Although Livermore (LLNL), which plans to make its pellets on site, does not release anticipated costs, the Laboratory for Laser Energetics at the University of Rochester also makes similar deuterium-tritium balls. “The reality now is that the annual budget to make targets that are used at Rochester is several million dollars, and they make about six capsules a year,” Morse says. “So you might say those are $1 million a piece.” LLNL can only blast one pellet every few hours, but in the future, targets will need to cycle through the chamber with the speed of a Gatling gun consuming almost 90,000 targets a day (Moyer).

Nelson F (2022) Scientists Achieved Self-Sustaining Nuclear Fusion… But Now They Can’t Replicate It.  ScienceAlert.

In August 2021, headlines made it sound like fusion had occurred at Lawrence Livermore National Laboratory.  But they haven’t been able to replicate that experiment. It’s hard to do because heat and energy can escape so easily.  The hope is that if ignition can be reached the fusion reaction will power itself, producing more energy than was needed to create the ignition.  And it takes a huge amount of power: a capsule of tritium and deuterium fuel is placed in the center of a gold-lined depleted uranium chamber and 192 high-energy lasers fire at it at it to create a bath of intense x-rays.  The four attempts since the good one have only produced half as much energy. If they can’t figure out why, then they can’t scale fusion up.

References

Clery D (2022) Explosion marks laser fusion breakthrough. Science 378:1154-1155

Genkina R (2022)  Fusion “Breakthrough” Won’t Lead to Practical Fusion Energy. IEEE Spectrum   https://spectrum.ieee.org/national-ignition-facility-impractical

Hunt T (2022) The fusion dream comes through at Lawrence Livermore lab. Pleasanton Weekly.

LLNL (2021) Fusion supports the stockpile. Lawrence Livermore National Laboratory. https://lasers.llnl.gov/news/fusion-supports-the-stockpile

Mecklin J (2022) The Energy Department’s fusion breakthrough: It’s not really about generating electricity. The Bulletin of the Atomic Scientists. https://thebulletin.org/2022/12/the-energy-departments-fusion-breakthrough-its-not-really-about-generating-electricity/?utm_source=Newsletter&utm_medium=Email&utm_campaign=MondayNewsletter122022&utm_term=NuclearRisk

Tollefson J et al (2022) Nuclear-fusion lab achieves ‘ignition’: what does it mean? Nature. https://www.nature.com/articles/d41586-022-04440-7