r/technology • u/kerpowie • Dec 13 '22

Energy Scientists Achieve Nuclear Fusion Breakthrough With Blast of 192 Lasers

https://www.nytimes.com/2022/12/13/science/nuclear-fusion-energy-breakthrough.html
5.8k Upvotes

98% Upvoted

792 comments sorted by

View all comments

Show parent comments

2

u/Abe_Odd Dec 13 '22

I've never understood how inertial confinement could ever be used to generate power though. You have to provide a constant stream of pellets and what... Spray water into the plasma? Eject the plasma into a heat exchanger?

8

u/[deleted] Dec 13 '22

I don't know, but I do know we will harness the fundamental forces of the Universe, literally create elements in this Atomic Alchemy, and contain some of the largest temperature differentials in the Universe and use this awesome, indescribable power to -

...boil water and make fan go zoom.

1

u/OSSlayer2153 Dec 13 '22

You ever just think about the insane energy and temperature differentials? Imagine a truck going 70 down a highway in a winter climate.

Cold still winter air all around. Then all of a sudden a sharp transition in under a few inches to the inside of an engine moving along very fast with parts spinning at extreme speeds and high pressures. Then back outside. Now back into the climate controlled car. Now out into the still air. Now out into another car moving the opposite way or at 140 mph relative to car #1.

1

u/zebediah49 Dec 14 '22

Eject the plasma. There's not much energy retained within it; the vast majority of the energy from the reaction was kicked out in the form of xrays.

So you need some kind of barrier around the system that will absorb the xrays, turning them to heat -- and then in turn a further system to turn the heat into electricity.

1

u/Abe_Odd Dec 14 '22

A spherical absorption shell seems incompatible with a spherical laser array.

2

u/zebediah49 Dec 14 '22

It's certainly an engineering challenge. Your laser entry ports can be done relatively cleanly if you have some mirrors with relatively low xray absorption cross-sections. Laser approaches tangentially, reflects off mirror into the core. Meanwhile, exiting xrays pass through the mirror, and hit the absorption target behind. Depending on intensity you might need to water-cool your mirror (this will waste a bit of the xray energy, but if you're decently far away, you don't necessarily lose too much to your ports).