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45°C cooling design cuts data center water use to near zero

blogs.nvidia.com

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Re: 45°C cooling design cuts data center water use to near zero

#211

Post by LazyGooze »

bbor wrote: post #187
MobiusHorizons wrote: post #183

Earlier quoted context omitted.

Windows are harder to insulate than walls anyway, but the most important insulation is in the roof because heat rises, so skylights would leak even more heat than normal windows already do.

Your logic is solid, but their usage kinda implies the opposite (that skylights would make summers worse, not winters). That seems possible given the obvious dynamics of increasing the amount of direct sunlight, but based on a quick Kagi the overall effect is actually good for both summer and winter if used instead of windows rather than in addition to windows: Introducing skylights allows the total fenestration area…

"fenestration" - I love that word!

Re: 45°C cooling design cuts data center water use to near zero

#212

Post by dzhiurgis »

verve_rat wrote: post #194
eru wrote: post #188

Earlier quoted context omitted.

> This brings the value to the local community of a nearby datacenter up from near zero to potentially a few million dollars per year. You are not wrong, but the whole issue is a bit silly: there should be legal ways for data centres (and other commercial operations) to just send a few million dollars a year to whichever community they need to convince; instead of having to dress it up as free heating.

But paying the money is less resource efficient than using the waste heat for a productive use. As a general rule we should probably insensitvise good use of resources that benefit the general population.

Im general. But the way AI is growing is not a general case, but exponential. It shouldn’t be slowed down by generalisations.

Re: 45°C cooling design cuts data center water use to near zero

#213

Post by dzhiurgis »

marcus_holmes wrote: post #195
badpun wrote: post #33

Earlier quoted context omitted.

European cities are doing it already.

Blew my mind living in a Berlin apartment, that the heating & hot water was managed centrally for the entire block (not the apartment block, the whole city block). Too used to Anglo cities where everyone does for themselves.

My parents city in eastern Europe just recently switched from burning russian oil to biomass. Even then prices are constantly increasing while converting entire building to heat pump would drop prices by half. However it’s near impossible due to bureaucracy.

Re: 45°C cooling design cuts data center water use to near zero

#214

Post by PunchyHamster »

amluto wrote: post #12

This opens up an interesting synergy: district heating. 45C is low but not unworkable for a district heating loop, and a data center might be able to make a nice pitch to a community if the data center offers to provide heat to a district heating system for free. This brings the value to the local community of a nearby datacenter up from near zero to potentially a few million dollars per year. Summer is still an issu…

> 45C is low but not unworkable for a district heating loop,

*55C is on the output, read article first pls

Main problem is that it wouldn't work with buildings designed for higher heating temperature so it is limited to new builds. And it is not limited just to replacing heaters, hot water system is also designed to work with higher temperatures so heat exchanger used would have to be significantly larger

Another one is that load is not constant on both sides and not exactly something that can be increased on demand (unless you're fine with burning cycles just to electrically heat, but that's massively inefficient)

Re: 45°C cooling design cuts data center water use to near zero

#215

Post by brainwad »

badpun wrote: post #33
amluto wrote: post #12

This opens up an interesting synergy: district heating. 45C is low but not unworkable for a district heating loop, and a data center might be able to make a nice pitch to a community if the data center offers to provide heat to a district heating system for free. This brings the value to the local community of a nearby datacenter up from near zero to potentially a few million dollars per year. Summer is still an issu…

European cities are doing it already.

Yep, my European apartment has been heated with waste heat from a nearby data centre since 2013: https://eicher-pauli.ch/referenzen/ewz-waermeverbund-binz-zu...

Re: 45°C cooling design cuts data center water use to near zero

#216

Post by PunchyHamster »

bbor wrote: post #187
MobiusHorizons wrote: post #183

Earlier quoted context omitted.

Windows are harder to insulate than walls anyway, but the most important insulation is in the roof because heat rises, so skylights would leak even more heat than normal windows already do.

Your logic is solid, but their usage kinda implies the opposite (that skylights would make summers worse, not winters). That seems possible given the obvious dynamics of increasing the amount of direct sunlight, but based on a quick Kagi the overall effect is actually good for both summer and winter if used instead of windows rather than in addition to windows: Introducing skylights allows the total fenestration area…

at low low cost of feeling like in cage.

Like, it's good idea for a warehouse, limited for housing, people want windows

Re: 45°C cooling design cuts data center water use to near zero

#217

Post by PunchyHamster »

marcus_holmes wrote: post #195
badpun wrote: post #33

Earlier quoted context omitted.

European cities are doing it already.

Blew my mind living in a Berlin apartment, that the heating & hot water was managed centrally for the entire block (not the apartment block, the whole city block). Too used to Anglo cities where everyone does for themselves.

It makes a lot of sense when there is waste heat. But in places where there isn't, having per house or per apartment block heating unit is preferable because you cut on transmission losses and infrastructure cost

Re: 45°C cooling design cuts data center water use to near zero

#218

Post by close04 »

bbor wrote: post #187
MobiusHorizons wrote: post #183

Earlier quoted context omitted.

Windows are harder to insulate than walls anyway, but the most important insulation is in the roof because heat rises, so skylights would leak even more heat than normal windows already do.

Your logic is solid, but their usage kinda implies the opposite (that skylights would make summers worse, not winters). That seems possible given the obvious dynamics of increasing the amount of direct sunlight, but based on a quick Kagi the overall effect is actually good for both summer and winter if used instead of windows rather than in addition to windows: Introducing skylights allows the total fenestration area…

A home with smaller windows is harder to sell so almost nobody builds homes with smaller windows just because they put in a skylight. Small windows make rooms feel smaller and claustrophobic. A skylight gives light but not a view, and large windows give houses a modern look, efficiency be damned. If you search for "modern house" all you see is walls of glass.

Re: 45°C cooling design cuts data center water use to near zero

#219

Post by indigo945 »

RachelF wrote: post #97
why_at wrote: post #72

Maybe I'm being dumb, but I don't understand what the innovation is here. I get that they're using liquid coolant at higher than usual temperatures, but why couldn't they do that before? Most of the comparison in the article is for air cooled datacenters but what about other liquid cooled ones? Surely in all the previous datacenters that have been designed there has been someone doing the math and determining what te…

The "innovation" is that everything is now attached to a watercooled block. The rest is marketing: The Cray supercomputer were fluid cooled back in the 1980's, the entire board had an inert liquid flowing across it.

    > The Cray supercomputer were fluid cooled back in the 1980's, the entire 
    > board had an inert liquid flowing across it.
You can still do this with any computer, by the way: just submerge the entire board in motor oil. Slightly smelly and might make a mess, but absolutely workable.

Re: 45°C cooling design cuts data center water use to near zero

#220

Post by Toutouxc »

If anyone else is disappointed by the terrible AI slop article: It's about a fully liquid cooled data center design.

The usual way to cool servers is with air and heatsinks attached to the hot hardware, similar to how your desktop computer or laptop works. As the hardware gets denser and more powerful, you need bigger and bigger heatsinks and cooler air blown over them. At some point you can't make the heatsinks bigger because of space constraints, and you can't blow the air faster (because of noise and efficiency), so you need cooler air. That's when you start running chillers that evaporate water to cool your intake air. This is the huge water consumption that we'd like to avoid.

The next step is, obviously, liquid cooling. Again, this is similar to your fancy gaming desktop. You can dump a lot of heat to a liquid medium through a small heat exchanger inside, where you're space constrained, and you can run the liquid through a gigantic heat exchanger outside, despite the temp delta between your coolant and outside air being pretty small.

This article is about a system that's FULLY liquid cooled — CPUs, GPUs, memory, networking, the whole thing. That's the actual cool part (pun unintended). On top of that, their solution is optimized to be able to run the coolant quite warm — this obviously limits the heat flux at the hardware side, but it allows you to run the outside heat exchangers "dry", i.e. without wasting any water for its latent heat.

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