Hacker News Reader

Comment by wizardforhire | Hacker News Reader

Another notch on the belt for a cryocooler boom.

Oh “superconducting is hard”, “if only we had high temperature superconductors”. All valid, but if we work with what we got and disrupt cyrocoolers make them a commodity like magnetrons all those laments become moot.

Prove me wrong.

View on HN

Also notable because heat rejection on that scale till you enter the superconducting regime is a reinforcing loop: the device no longer makes heat, you just need to keep the environmental heat out.

And the power requirement to maintain temperature scale by surface area, not volume. Same reason thermal power storage using giant piles of sand is theoretically viable.

Is the cost of cryocoolong capex or Opex dominated?

Are you referring to the hardware cost vs operating cost? Or how the units are financed?

That's what it means. Some things are expensive to buy, some things are expensive to run, and some things are both.

The terms in that context are fixed cost vs variable cost.

CapEx vs OpEx deals with how the equipment is managed financially. Buy vs lease/rent/IAAS. Good examples here https://centersquaredc.com/blog/choosing-the-best-data-cente...

capex = capital expenditure; opex = operational expenditure.

There's some theorem about investments that says it doesn't matter how they are financed. A good one is good, and a bad one is bad, whether or not you use debt.

I'll bet you I can find a way to finance a good deal that turns it into a bad one. The other way around seems harder.

> it doesn't matter how they are financed

If you have spherical banks in a vacuum, you can simply follow "capital_opex = capex * interest_rate" and then "profit = revenue - total_opex".

But things tend to not work that way on practice.

Would running a cryocooler spend more energy than a superconducting CPU / GPU would save?

>The 2.5 GHz prototype uses 80 times less energy than its semiconductor counterpart, even accounting for cooling

It's in the header of the article.

The way it reads though is that the chip itself uses less power but still needs to be cooled which takes a lot of energy (traditionally)

>even accounting for cooling

No.

stuff like this makes me wonder what the distribution on human context limits is.

It is very small, but humans tend to internalize knowledge as they read giving essentially infinite but lossy context length. Those posters failed to internalize the message here so they get the wrong knowledge out of the message.

That was both self referential and ignorant of what? Oh. .. forgetting. Or the simulatianiety. Or not. I am stuck in a zero sum post, or not. A comma uses less energy than three dots,

I'm fond of this argument but I would point out that magnetrons are remarkably simple devices once you figure out how the waves are interacting.

I’ve been thinking about making cheaper cryocoolers for CO2 condensation. I’d love to hear your perspective on other applications :)

So someone else needs to prove a negative, that there exists no possible technology that will "disrupt" cryocoolers by bringing them to an unspecified price/performance point by an unspecified time in the future to service an unspecified computing use-case?

That seems more than a little unfair. :p

> someone else needs to prove a negative, that there exists no possible technology that will "disrupt" cryocoolers

Look at the Wikipedia references for crycoolers [1]. Note the dates and volume. Now look at room-tempuerature superconductors [2].

1990 vs 2023. 5 vs 57. OP is arguing that a greater fraction of high-temperature superconducting research dollars might find purchase in improving the cryocooler than we presently spend.

[1] https://en.wikipedia.org/wiki/Cryocooler#References

[2] https://en.wikipedia.org/wiki/Room-temperature_superconducto...

> Now look at room-tempuerature superconductors [2].

As a tangent: Don't forget to look at pressures too. Some newer superconductors that are near-room-temperature aren't quite as exciting when it turns out that requires over 1.5 million times normal atmospheric pressure. ("Hey, I think I over-tightened the CPU heatsink...")

Ex: https://en.wikipedia.org/wiki/Lanthanum_decahydride

The problem is, cryocooler theory is pretty well established and "solved at this point, so there is no reason to expect something completely new phenomena there, just some engineering improvements. Solid-state physics, on the other hand, is just computationally infeasible to "solve", so there is a plenty of possibility to discover something unpredicted.

> cryocooler theory is pretty well established and "solved at this point

What are you quoting? What is "cryocooler theory"?

Thermodynamics. Should have been "solved", missed the closing parenthesis.

The latter aren't being researched for CPUs, which are small things. They're for applications like long-distance power transmission, electric motors, and more. Things which aren't feasible to cryocool.

> long-distance power transmission

IIRC unlikely to change quickly even with higher-temp superconductors, since it would mean splicing in new power-grid segments that transfer direct-current instead of alternating, and then you have losses in conversion too.

We have plenty of long-distance HVDC links, one of the most prominent being https://en.wikipedia.org/wiki/Quebec_%E2%80%93_New_England_T..., which also helped isolate Quebec from the Northeast blackout of 2003 https://en.wikipedia.org/wiki/Northeast_blackout_of_2003

Reply on news.ycombinator.com