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Antares achieves criticality of Mark-0 reactor

antaresindustries.com

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Re: Antares achieves criticality of Mark-0 reactor

#71

Post by pfdietz »

dpark wrote: post #68
pfdietz wrote: post #61

Earlier quoted context omitted.

I don't think that's the case, if launch costs are low enough. The options you describe there are quite expensive. Reprocessing costs somewhere in the neighborhood of $1000/kg. Even fast reactor have trouble disposing of the seven very long lived fission products. A fully reusable launcher might get costs down to $10/kg to LEO. Even if one had to wrap the waste in 10x its mass in launch armor this could be much cheap…

Why would launch costs be low? $10/kg is fantasy land. UPS won’t ship a kilogram across the country for $10. And who wants spent nuclear fuel in low earth orbit? This is a far worse location for spent fuel than buried in a bunker. This is a worse location than Times Square.

Why wouldn't they be low? In the limit, if launch becomes operationally similar to air travel, costs will be a few times propellant cost. And propellant is very cheap. LOX is almost free (the second cheapest industrial liquid after water) and liquid methane isn't very expensive either.

Low earth orbit would just be where it's transferred to something to carry it farther out, for example using solar-electric engines.

For all this, remember it isn't done immediately, it's done in (say) 300 years when the short lived fission products are mostly gone.

Re: Antares achieves criticality of Mark-0 reactor

#72

Post by pfdietz »

rayiner wrote: post #56
pfdietz wrote: post #39

Earlier quoted context omitted.

We don't actually know how much that cost France, sine it was mixed in with their military nuclear effort. French auditors threw up their hands trying to figure out the actual costs. What we do know is their attempt to build more NPPs now has gone spectacularly tits up, with costs completely out of control. This should make one view their earlier efforts with great suspicion. Have they become much worse, or were earl…

Costs are out of control due to nuclear regulation.

This is the conspiracy theory reasoning I was talking about. Nuclear is wonderful, but a global omnipotent green conspiracy has hobbled it.

Or, maybe, it really is complicated and needs regulation to keep it sufficiently safe in a world where corners are always cut.

Re: Antares achieves criticality of Mark-0 reactor

#73

Post by actionfromafar »

tech_ken wrote: post #59

From the article: > We said criticality in 2026, electricity production in 2027, and power to the warfighter in 2028. Are there any other examples of land-based militaries using nuclear power? Seems kind of like since they can't talk about the energy transition or w/e this has to be a military thing instead.

"Stalin is proud to support the rebirth of Soviet Russia’s nuclear industry and ensuring soviets have access to affordable, reliable and secure energy for generations to come". Always mention the fearless leader.

Re: Antares achieves criticality of Mark-0 reactor

#74

Post by api »

dpark wrote: post #68
pfdietz wrote: post #61

Earlier quoted context omitted.

I don't think that's the case, if launch costs are low enough. The options you describe there are quite expensive. Reprocessing costs somewhere in the neighborhood of $1000/kg. Even fast reactor have trouble disposing of the seven very long lived fission products. A fully reusable launcher might get costs down to $10/kg to LEO. Even if one had to wrap the waste in 10x its mass in launch armor this could be much cheap…

Why would launch costs be low? $10/kg is fantasy land. UPS won’t ship a kilogram across the country for $10. And who wants spent nuclear fuel in low earth orbit? This is a far worse location for spent fuel than buried in a bunker. This is a worse location than Times Square.

$10/kg isn’t fantasy land if we have fusion rockets, but then we don’t need fission power anymore. :)

Re: Antares achieves criticality of Mark-0 reactor

#75

Post by bigbadfeline »

Gud wrote: post #69
netsharc wrote: post #58

Earlier quoted context omitted.

Sigh, everything is being done for political purposes, now Dear Leader Donny can proclaim on the quartermillenial celebrations that "we achieved a nuclear milestone!". And maybe add that this is possible because of his nuclear physics genius abilities. I wouldn't even be surprised if the achievements are like "Full-Self Driving", announced hastily with boasts and then slowly revealed to be full of Elon.

Honestly these political rants contribute very little, no offence.

> Honestly these political rants contribute very little, no offence.

What do the other comments contribute? Do they solve inflation, wars, monopolization? Small-picture comments have small audience, like, how many people have access to nuclear materials and gear to make use of the information provided here? In other words "political rants" have their place and in many cases they are more valuable than the rest.

Re: Antares achieves criticality of Mark-0 reactor

#76

Post by pfdietz »

dpark wrote: post #66
pfdietz wrote: post #42

Earlier quoted context omitted.

IMO, the long term solution will be to simply launch the waste into space. With low enough launch costs the extra mass needed to armor the waste against accidents becomes tolerable.

Unless you live in Sci Fi future where space travel is magically free, this is a pretty bad deal since sending a pound of spent nuclear fuel out of earth orbit takes 50+ pounds of fuel. Sending all the spent nuclear waste into space would be something like 10 million tons of fuel.

It doesn't have to be free, it just has to have a low cost. And remember, we're talking not about the cost now, but the cost up to centuries in the future. The ultimate time limit is set by when spent fuel stops being self-protecting against amateur diversion of the plutonium, which is 300-500 years.

> 50+ pounds of fuel

Just out of curiosity, how much do you think LOX/LNG propellant costs?

Re: Antares achieves criticality of Mark-0 reactor

#77

Post by pfdietz »

api wrote: post #74
dpark wrote: post #68

Earlier quoted context omitted.

Why would launch costs be low? $10/kg is fantasy land. UPS won’t ship a kilogram across the country for $10. And who wants spent nuclear fuel in low earth orbit? This is a far worse location for spent fuel than buried in a bunker. This is a worse location than Times Square.

$10/kg isn’t fantasy land if we have fusion rockets, but then we don’t need fission power anymore. :)

Fusion would be useless for launch to orbit. Even fission sucks for that. It's really hard to beat the cost and power density of chemical rockets.

Re: Antares achieves criticality of Mark-0 reactor

#78

Post by dpark »

pfdietz wrote: post #71
dpark wrote: post #68

Earlier quoted context omitted.

Why would launch costs be low? $10/kg is fantasy land. UPS won’t ship a kilogram across the country for $10. And who wants spent nuclear fuel in low earth orbit? This is a far worse location for spent fuel than buried in a bunker. This is a worse location than Times Square.

Why wouldn't they be low? In the limit, if launch becomes operationally similar to air travel, costs will be a few times propellant cost. And propellant is very cheap. LOX is almost free (the second cheapest industrial liquid after water) and liquid methane isn't very expensive either. Low earth orbit would just be where it's transferred to something to carry it farther out, for example using solar-electric engines.…

I think the onus is on you to explain why costs would drop by >3 orders of magnitude (>4 accounting for the 10x launch armor). It’s something like $1500/lb on a fully loaded Falcon Heavy and all indications are that SpaceX isn’t making money at that price.

Plus even if this were free, “shoot 180k tons of nuclear waste into space” seems like a terrible idea in general. It’s one of those ideas that make sense only until you think about the ramifications. What happens when inevitably one of the 3 thousand Falcon heavy rockets explodes and the armor fails and we spread nuclear waste over 3 states?

Re: Antares achieves criticality of Mark-0 reactor

#79

Post by pfdietz »

dpark wrote: post #78
pfdietz wrote: post #71

Earlier quoted context omitted.

Why wouldn't they be low? In the limit, if launch becomes operationally similar to air travel, costs will be a few times propellant cost. And propellant is very cheap. LOX is almost free (the second cheapest industrial liquid after water) and liquid methane isn't very expensive either. Low earth orbit would just be where it's transferred to something to carry it farther out, for example using solar-electric engines.…

I think the onus is on you to explain why costs would drop by >3 orders of magnitude (>4 accounting for the 10x launch armor). It’s something like $1500/lb on a fully loaded Falcon Heavy and all indications are that SpaceX isn’t making money at that price. Plus even if this were free, “shoot 180k tons of nuclear waste into space” seems like a terrible idea in general. It’s one of those ideas that make sense only unti…

Falcon Heavy is more expensive per kg than F9, because it throws away more things. SpaceX flies it for certain military missions but you will note they launch their own stuff on F9.

A full launch on F9 (with recovered S1) is estimated to cost $15M and can put up to 17,600 kg into LEO, or $850/kg.

> (>4 accounting for the 10x launch armor).

You're double counting there. 3x would be just fine even with 10x launch armor.

> seems like a terrible idea in general

And here's the problem: you started from an emotional reaction and are trying to rationalize that.

Re: Antares achieves criticality of Mark-0 reactor

#80

Post by pfdietz »

rayiner wrote: post #67
tech_ken wrote: post #65

Earlier quoted context omitted.

Tech development != tech tree, history is nonlinear and ecological. Linear, unlockable "tech trees" are an ahistorical fantasy necessary to make some video games fun and digestible. Applying them to the real world is like trying to win a war by replicating the Battle of Helm's Deep or something.

I’m not saying it’s literally a tree. My point is that we need vastly more power to upgrade to the next level of civilization.

How do you know nuclear is even on the "tech tree", rather than being a blind alley? Isn't this argument just assuming what you're trying to show?
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