Fusion News Ignites Optimism • Hacker News Board

Re: Fusion News Ignites Optimism

#61

Post by XorNot » Thu, Sep 30, 2021, 12:35 PM UTC

danpalmer wrote: post #12

xupybd wrote: post #7

Earlier quoted context omitted.

I don't think it will as it should be radically cheaper. It should come with an economic improvement.

It might be in the long term, but the same can essentially be said for nuclear (fission) power – the materials cost is low (compared to fossil fuels), but due to the extremely high capex needed to build a plant it's considered expensive. I think the first ~50 years of fusion projects are likely to be very expensive and I'd expect that reputation to stick.

Depends on the return. Solar was too expensive until it was a better investment then a coal plant.

Re: Fusion News Ignites Optimism

#62

Post by pfdietz » Thu, Sep 30, 2021, 12:53 PM UTC

danpalmer wrote: post #59

pfdietz wrote: post #36

Earlier quoted context omitted.

No, the problem with nuclear power stations is they are way too expensive. Fusion promises to make this main problem worse, not better. Fusion is a great example of solving the wrong problem.

This is a really good point, and could well be true, although I think it's a bit more complicated. Fission has two problems: the emotional one – weapons/danger, and the practical one – cost. Yes weapons could be a practical issue, but I think it's more an "emotional" issue. The question is, is it only the practical reason that is preventing widespread adoption of fission power? On the surface, maybe! Unpacking it a b…

Cost has been the problem with fission. The first nuclear buildout in the US ended because of market forces, not because of TMI. Costs were higher than promised, a constant problem then and now. Electricity demand growth slowed, and with the passage of PURPA in 1978 non-utility sources started to be added to the grid. Nuclear could not compete with them even then.

Nuclear's long term prospects are poor, for one big reason: it has never shown good experience effects. This means its cost has not come down with time. Any technology like that is doomed, if it has competitors that are improving. PV started off orders of magnitude more expensive than nuclear (levelized cost of energy) but now is much cheaper, because PV improved 20% for each doubling of cumulative production and nuclear didn't.

Re: Fusion News Ignites Optimism

#63

Post by pfdietz » Thu, Sep 30, 2021, 12:56 PM UTC

willis936 wrote: post #60

pfdietz wrote: post #52

Earlier quoted context omitted.

ITER may deliver something tangible, but also something that is not on any realistic path to being competitive. It's far too large for the power it (or DEMO) would produce. It's also possible ITER will just deliver a negative outcome, if they can't figure out how to control disruptions sufficiently. A reactor that violently breaks itself is not something anyone would want to buy.

The primary reason for this is the use of Nb3Sn LTS confinement coils. REBCO is the next wave.

ITER has volumetric power density 400x worse than a PWR reactor vessel. ARC as described in the arxiv paper is just 40x worse. Better, but not by enough.

Re: Fusion News Ignites Optimism

#64

Post by pfdietz » Thu, Sep 30, 2021, 1:12 PM UTC

blake1 wrote: post #29

wnkrshm wrote: post #22

Earlier quoted context omitted.

Use of fusion as an energy source removes a lot of threats our civilizations are facing but it also comes with some caveats rooted in human behavior. Human energy consumption has always gone up when the supply got more efficient, from coal to oil to fission. While here, the power generation itself won't have such a drastic impact (unless humanity overdoes it, though, we seem to always do that) but maybe more power me…

Your first point is not supported by the data. The US Energy Information Agency keeps track of this[1], and the per capita energy use peaked around 2000. And we are much better at running an energy-efficient economy: energy use/real $ GDP has halved in the last century. The trend may not continue. People might start to do much more air travel (which would require massive runway building). Global warming might increas…

> the per capita energy use peaked around 2000.

1980, actually.

Re: Fusion News Ignites Optimism

#65

Post by Shadonototra » Thu, Sep 30, 2021, 1:17 PM UTC

danjac wrote: post #37

Great! Does that mean fusion is going to be here in just 10 years in the future as opposed to the 20 years in the future it's been for the last 50 years?

Now that china is advancing with its mini artificial Sun, you can be sure the west will do whatever it takes to "catch up"

Re: Fusion News Ignites Optimism

#66

Post by myrmidon » Thu, Sep 30, 2021, 1:18 PM UTC

tsimionescu wrote: post #39

myrmidon wrote: post #32

Earlier quoted context omitted.

Not sure I agree with this; I just don't see the weapon applications of fusion power... Also most participants are either already nuclear powers (US, EU, Russia, China, India) or could just build thermonuclear weapons already if they wanted to (Korea, Japan, etc.) Or maybe you had completely different weapon applications in mind?

No country in the world that doesn't already have them can "just build nuclear weapons if it wanted", international treaties are extremely prohibitive of that. In particular, if Japan wanted to build a nuclear weapon, it would face tremendous opposition from China, while S Korea would face the same from both China and N Korea. Also, fission weapons tests are currently banned, which also indirectly bans fusion weapons…

> international treaties [...], political opposition

Are just reasons for countries to not want nuclear weapons. But if e.g. Japan announced a nuclear weapon program (or it was uncovered by foreign intelligence) I highly doubt that anyone could/would stop them-- hinder their economy or facilities with sanctions or sabotage, sure, but outright stop them from becoming a nuclear power? Unlikely.

IMO every bigger western-ish nation state has the ressources required to build nuclear weapons; they just lack motivation to do so.

Just consider that smaller states like France were already able to do this in the 1950ies, and relevant helper technologies (computer aided design, simulation, industrial control) are MUCH more accessible and advanced today.

Fusion research, on the other hand, is not going to help with the major challenge in becoming a nuclear power: it does not help with obtaining highly enriched fissile material.

If countries wanted to throw research funds at becoming a nuclear power, it seems infinitely more likely to me that those would go into "innovative reactor research" with the endgoal of producing HEU or plutonium.

Re: Fusion News Ignites Optimism

#67

Post by wnkrshm » Thu, Sep 30, 2021, 2:05 PM UTC

Someone wrote: post #58

neutronicus wrote: post #57

Earlier quoted context omitted.

Yeah, capital-E Energy is mostly for capital-W Work and thermodynamics. Once you refrigerate your living space and don't walk anywhere and everything you want is brought to your door what else are you going to do?

I’m not sure whether you’re serious, but: Bigger cars? Supersonic city trips to the other side of the world? Weekends in Antarctica? A week in one of SpaceX’s hotels? High-resolution screens on every wall of your home, plus the AC needed to keep your house cool? Reshape a mountain to improve your view? Transform lead into gold? Mine bitcoin? If energy were free, I foresee accelerated destruction of nature. At best, t…

This is an interesting read as to the possible caveats of fusion power [0]. It's interesting, whether one reaches the same conclusion as the plasma physicist who wrote the article or not.

[0] https://thebulletin.org/2017/04/fusion-reactors-not-what-the...

Re: Fusion News Ignites Optimism

#68

Post by tsimionescu » Thu, Sep 30, 2021, 2:23 PM UTC

myrmidon wrote: post #66

tsimionescu wrote: post #39

Earlier quoted context omitted.

No country in the world that doesn't already have them can "just build nuclear weapons if it wanted", international treaties are extremely prohibitive of that. In particular, if Japan wanted to build a nuclear weapon, it would face tremendous opposition from China, while S Korea would face the same from both China and N Korea. Also, fission weapons tests are currently banned, which also indirectly bans fusion weapons…

> international treaties [...], political opposition Are just reasons for countries to not want nuclear weapons. But if e.g. Japan announced a nuclear weapon program (or it was uncovered by foreign intelligence) I highly doubt that anyone could/would stop them-- hinder their economy or facilities with sanctions or sabotage, sure, but outright stop them from becoming a nuclear power? Unlikely. IMO every bigger western…

I agree with you that there are lower hanging fruit than fusion research for becoming a nuclear power.

I do not agree with you that Japan could in practice successfully acquire nuclear weapons with only economic sanctions to fear. I believe that China would be likely to declare war before allowing Japan to become a nuclear power, and I think it would have significant international support. Of course, that would be many years away, as a last resort if all else failed and their weapons program is nearing fruition. But I do believe it would happen eventually.

Re: Fusion News Ignites Optimism

#69

Post by motoboi » Thu, Sep 30, 2021, 3:57 PM UTC

tsimionescu wrote: post #25

motoboi wrote: post #21

Earlier quoted context omitted.

A single pellet contains a lot of atoms. The current process is able to fuse some of those but soon the plasma cools down. The goal is to start fusion by compressing the pellet using lasers and then use magnets to keep the plasma (charged, very hot gas/thing) confined to a small volume and hot enough so fusion becomes a chain reaction until all atoms of the pellet becomes a heavier element, when fusion stops (because…

In this case, is the pellet the highly precise gold holhraum described in the article? If that is the case, then isn't this whole thing obviously doomed to failure, given that the entire advancement described consisted of even more sophisticated methods of producing that holhraum?

The gold thing houses the pellet. It’s needed because the lasers by itself cannot compress the pellet. It’s the heat from the lasers that causes the gold thing to compress the pellet to the infernal pressure needed to trigger fusion.

Re: Fusion News Ignites Optimism

#70

Post by danpalmer » Thu, Sep 30, 2021, 4:22 PM UTC

pfdietz wrote: post #62

danpalmer wrote: post #59

Earlier quoted context omitted.

This is a really good point, and could well be true, although I think it's a bit more complicated. Fission has two problems: the emotional one – weapons/danger, and the practical one – cost. Yes weapons could be a practical issue, but I think it's more an "emotional" issue. The question is, is it only the practical reason that is preventing widespread adoption of fission power? On the surface, maybe! Unpacking it a b…

Cost has been the problem with fission. The first nuclear buildout in the US ended because of market forces, not because of TMI. Costs were higher than promised, a constant problem then and now. Electricity demand growth slowed, and with the passage of PURPA in 1978 non-utility sources started to be added to the grid. Nuclear could not compete with them even then. Nuclear's long term prospects are poor, for one big r…

> Nuclear's long term prospects are poor, for one big reason: it has never shown good experience effects.

Good point, I hadn't considered this. I would suggest that a possible cause for this is lack of investment though. We had the 1st generation. Most current reactors are gen-2 or gen-3. Gen 4 hasn't really started use, still in R&D I think. There are ideas for Gen 5 but no progress. Each generation seems to bring moderate energy improvements, and significant cost, safety, and waste management improvements, but the interest just isn't there.