Re:Nuclear physicist explains why fusion ignition is hailed ...
by pfdietz on Monday December 19, 2022 @10:48AM
(#34053429)
It should be noted that even if the lasers were 100% efficient, this result is not sufficient to achieve a practical fusion power plant. That target could produce maybe $0.02 worth of electrical energy. That's nowhere close to paying for the plant, even totally ignoring operating costs.
A real plant would need target yields 100 to 1000 times larger, with all the engineering issues that would entail.
Re:Nuclear physicist explains why fusion ignition is hailed ...
by Robotbeat on Monday December 19, 2022 @11:11AM
(#34053732)
Of course, because you learn to spark fire before you build a power plant. NIF is nothing like a power plant. It was designed for stockpile stewardship and for fusion ignition demonstration, and they intentionally cancelled efforts to solve the engineering challenges of making this into a power plant, because doing so was premature without the ignition breakthrough.
https://en.wikipedia.org/wiki/Laser_Inertial_Fusion_Energy
Credit: Mark Herrmann/LLNL
From this article: https://physicstoday.scitation.org/do/10.1063/PT.6.2.2022121...
Clear qualitative difference.
Additionally, this is laser energy, but the lasers aren’t used directly. They produce X-rays which are the ones that actually drive the ablative implosion of the fuel pellet. If you used X-rays directly, the gain value would be MUCH higher… I think by that measure, they would’ve achieved Q=1 back in 2013?
Note that hey COULD use the lasers directly to drive implosion but haven’t yet. The Hohlraum/X-ray/indirect method I think produces more consistent lighting on the target, and is more analogous to the operation of an H-bomb, which is partly what this entire process is intended to replicate. They may do future experiments to try direct drive, in preparation for actually using this as a power production method and improving the efficiency dramatically… in combination with far higher efficiency modern lasers, this could enable Q high enough for net electricity production.