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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

#221

Post by dist-epoch »

matt-p wrote: post #158
superluserdo wrote: post #107

Earlier quoted context omitted.

>Factor in pipe losses on the return leg and you're back at the data centre with maybe 35°C inlet rather than 45°C Surely having the input fluid being colder is a benefit, not a problem? Just run the fluid more slowly through the system?

In essence you can't really because slower flow rate makes the heat transfer less efficient. You'd be halfing the flow rate in that example.

Maybe you can use a heat exchanger, like in nuclear power plants, and separate the data center flow from the outside flow, so they can go at different speeds.

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

#222

Post by [deleted] »

loeg wrote: post #90
VorpalWay wrote: post #71

I never looked into this, but why would a datacenter consume water for cooling in the first place? Sure, they use some. But just like you fill up the cooling loop in a car, once it is there it just circulates between the heat source and radiators and/or heat exchangers, with perhaps some minimal top off needed (since flexible tubing isn't 100% water proof). Or are they for some unfathomable reason using evaporative c…

Evaporative cooling consumes less expensive electricity than air conditioning. Electricity is much more expensive than water (for the same cooling load) in most places DCs are located.

[deleted]

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

#223

Post by Version467 »

dzhiurgis wrote: post #212
verve_rat wrote: post #194

Earlier quoted context omitted.

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.

Surely there's something missing from your argument. It shouldn't be slowed down because it's growing exponentially?

Presumably you think that the end result of extreme and rapid ai growth is beneficial to most and that is why it shouldn't be slowed down? That arriving earlier at whatever end-point you have in mind will provide so much benefit that it's worth disregarding the pains to get there?

Or is there something else to your argument? Because if there isn't, you are staking an awful lot on your expectation coming true. Especially that going slower doesn't provide any worthwhile benefits to the outcome.

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

#224

Post by w4der »

shagie wrote: post #99
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…

Of old... https://web.archive.org/web/20210115152829/https://www.nrel.... It's got a "heat energy to/from campus" exchange in there. That's a link in March and the air temperature was 31°F. https://web.archive.org/web/20210708150410/https://www.nrel.... is later with air temperature of 68°F.

The diagram you shared has an open loop chiller, are those still needed as a backup?

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

#225

Post by ACCount37 »

spockz wrote: post #193
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…

In the Netherlands we are already transporting “waste energy” in the form of heat to greenhouses to warm them in winter. Also interesting that the article states that this engineering problem hadn’t been solved before. Google pioneered running chips hotter than before. Moreover, we have had water cooling in consumer setups for ages. (At least 30 years.) So what is new is that all chips have been attached to the loop.…

High end server PSUs also have liquid cooling now. I'm not quite sure of what temp ranges they run in though.

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

#226

Post by whateverboat »

spockz wrote: post #193
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…

In the Netherlands we are already transporting “waste energy” in the form of heat to greenhouses to warm them in winter. Also interesting that the article states that this engineering problem hadn’t been solved before. Google pioneered running chips hotter than before. Moreover, we have had water cooling in consumer setups for ages. (At least 30 years.) So what is new is that all chips have been attached to the loop.…

I think Nvidia are being a little disingenuous here. If I understand correctly, Bull/Eviden has already solved this problem and is in production in JUPITER.

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

#227

Post by mschuster91 »

chii wrote: post #191
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.

the datacenter doesn't have a few million dollars to spare. The heat is waste heat. If it cannot be recovered as a profitable source of energy, the datacenter won't be able to pay that few million dollars.

Recovery isn't the issue, the issue is that district heating systems are pretty much a rarity across the world for a number of reasons. Recovering waste heat - no matter if from datacenters, industrial processes or eve wastewater/sewage - is trivial, but getting the heat to somewhere it still can have a productive "secondary usage" is a massive and expensive problem.

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

#228

Post by FridgeSeal »

> In the right geography — somewhere with reliably cool outdoor air

Aaahh, there’s the catch. “Save resources on cooling by building your data centre somewhere cold, and pollute the surrounding environment by dumping your waste heat wholesale into that!”

Good job Nvidia, I almost thought we had something good there.

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

#229

Post by mschuster91 »

PunchyHamster wrote: post #214
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…

> Main problem is that it wouldn't work with buildings designed for higher heating temperature so it is limited to new builds.

That's no longer the case with modern, multi-stage high temperature heat pumps [1]. These consume more electricity, yes, but still achieve far better efficiency than straight burning fuel or resistive heaters.

[1] https://www.buderus.de/de/waermepumpe/hochtemperatur

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

#230

Post by alt227 »

indigo945 wrote: post #219
RachelF wrote: post #97

Earlier quoted context omitted.

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.

Mineral oil is the usual substance used, as its clear and non smelling.
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