261–270 of 289 posts
Earlier quoted context omitted.
No, it's not. If you get to arbitrarily define at what point you count "energy in" (as the NIF people are), you could also define a clever spot for MCF to be net positive.
NIF's definition of Q was defined by the National Academy of Sciences and is analogous to the Q that MCF uses.
Real Engineering published a video about Helion Energy company. I don't have the tools to filter out commercial BS, still it seems to me to be most promising effort. The idea to get electricity directly from magnetic fields instead of boiling water is very intriguing.
We didn’t have the compute power for any of this stuff in the 80’s. I did some reading a while back and discovered that there are elements of Computational Fluid Dynamics that became state of the art around 1990, so we are maybe two decades behind, not five.
Most interesting fact from the article. At the system level it took 300 million Joules to produce 3 Million a 1% return - so still a very long way to go! With this kind of approach I can’t see how fusion can ever be cheap, the capital costs are enormous. Better to focus on standardised production lines for small fission reactors.
That's not the only big challenge. The fuel pellets are 1mm diameter hollow spheres machined out of diamond to extreme precision and filled with a tiny amount of deuterium-tritium gas inside. The pellets need to be carefully cooled to cryogenic temperatures so that the gas condenses evenly around the inside of the pellet, in order to maintain the near-perfect geometry needed for ignition. Once the pellet is hit with…
Could they really fire this design more than twice a minute?
Earlier quoted context omitted.
Didn’t we already know it’s just an engineering problem by virtue of the sun existing?
Boy, the HN pedantry is potent this morning. The fact that black holes exist does not mean that we can spin one up to harvest it's hawking radiation for power. It's not just an engineering problem. That's not what that phrase means.
Earlier quoted context omitted.
I'm not sure if it's theoretically impossible. But it's certainly an incredible challenge to build a high efficiency laser system that can consistently generate many pulses per second without degrading either the laser head itself or any associated micro-focussing optics. Can we stop pretending this isn't about nuclear weapons research and - basically - continued funding? LLNL is at least a decade behind its initial…
>Can we stop pretending this isn't about nuclear weapons research The laser practicality issue that prevents this from directly becoming a power source would also be a major barrier to its application as a weapon. The laser fires in the UV-B (351 nm), which is scattered and attenuated by air, to say nothing of smoke or dust; it also requires incredibly high targeting precision ( I ascribe a small possibility to its u…
Still unconvinced why this is such a major breakthrough - it may be the first net-positive controlled fusion, but the distinction between controlled and uncontrolled fusion is a bit academic in this case. In uncontrolled fusion ( https://en.wikipedia.org/wiki/Thermonuclear_weapon ), you are using a nuclear fission primary stage to generate enough energy to start the fusion reaction in the secondary stage. In the NIF,…
This comment sums up HN beautifully: "Here's an article from a subject matter expert on this topic, but I'm going to go ahead and ignore everything that was said because it doesn't fit my narrative."
Most interesting fact from the article. At the system level it took 300 million Joules to produce 3 Million a 1% return - so still a very long way to go! With this kind of approach I can’t see how fusion can ever be cheap, the capital costs are enormous. Better to focus on standardised production lines for small fission reactors.
That's not the only big challenge. The fuel pellets are 1mm diameter hollow spheres machined out of diamond to extreme precision and filled with a tiny amount of deuterium-tritium gas inside. The pellets need to be carefully cooled to cryogenic temperatures so that the gas condenses evenly around the inside of the pellet, in order to maintain the near-perfect geometry needed for ignition. Once the pellet is hit with…
I'm just an interested layman on the sideline watching from "old Europe" but can't help but ask: Is everything okay with your science-media sector over there in the US? Lately, I've been asked to believe this weird wormhole story[0] and now this "major breakthrough" in fusion ignition? This all smells like too much marketing BS to me. [0] https://www.quantamagazine.org/physicists-create-a-wormhole-...
Earlier quoted context omitted.
I'm not sure if it's theoretically impossible. But it's certainly an incredible challenge to build a high efficiency laser system that can consistently generate many pulses per second without degrading either the laser head itself or any associated micro-focussing optics. Can we stop pretending this isn't about nuclear weapons research and - basically - continued funding? LLNL is at least a decade behind its initial…
>Can we stop pretending this isn't about nuclear weapons research The laser practicality issue that prevents this from directly becoming a power source would also be a major barrier to its application as a weapon. The laser fires in the UV-B (351 nm), which is scattered and attenuated by air, to say nothing of smoke or dust; it also requires incredibly high targeting precision ( I ascribe a small possibility to its u…
We already have a stable fusion going. It's 8 light minutes away. All you have to do is to point a solar panel at it to harvest the energy.