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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

#201

Post by rswail »

quickthrowman wrote: post #96
bozhark wrote: post #86

Earlier quoted context omitted.

But you can do that in a closed system and recapture the water

You cannot have evaporative cooling without evaporating some water into the atmosphere. A closed circuit cooling tower still has water spraying onto the closed loop process water heat exchanger coil and mixing with atmospheric air to evaporate and cool the process water indirectly instead of evaporating and recirculating the process water that doesn’t evaporate directly like in an open-loop cooling tower. I suppose y…

> I suppose you could condense the evaporated water somehow by using a chilled umbrella or some other ridiculous contraption above the cooling tower, but why would you do that?

Specifically to reduce the ongoing demand for water.

DCs need to get to net-zero on their energy requirements and their water consumption.

They are already losing their political license to operate because they're not.

That's independent of the noise and other impositions on the local communities.

For a DC to be politically acceptable it must be:

* Net zero emissions on energy consumption, preferably powered by renewables in addition to the existing local supply.

* Net zero on water consumption, especially fresh/drinking water from local supplies.

* Low to no noise or other pollution.

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

#202

Post by lrasinen »

hiAndrewQuinn wrote: post #179
lrasinen wrote: post #21

Earlier quoted context omitted.

Microsoft's already building data centers hooked up to district heating (Espoo and Kirkkonummi, Finland). Heatpumps are amazing. (Seasonal heat storage is also a thing, Espoo's neighbours have tens of GWh of storage, with a new 90 GWh cavern in the works. Not sure if the systems are interlinked.)

Don't forget XTX Markets in Kajaani! At least last I heard. Free heating for an entire city in exchange for being allowed to build out a data center is a pretty good deal.

Nice!

Apparently the local supercomputer cluster in Kajaani has also been hooked up in 2021 and is responsible for a fifth of heating.

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

#203

Post by rswail »

mchusma wrote: post #22

This is also the type of thing that makes space based data centers more viable. I was previously more skeptical on the concept but have come around. I do think ground based centers will have better economics when they can be built though, and this addresses noise and water complaints which are the big 2 regional complaints. It seems like lots of bottlenecks are getting solved quickly, except for maybe memory.

Space based data centers make no economic sense compared to land based.

The only reason is to remove them from local/regional, and potentially national/international jurisdictions.

Oh, and of course, the other reason is to give SpaceX to have a reason for xAI to be part of its structure.

Starlink makes sense, LEO comms using a mesh makes sense.

LEO/geosync satellite data processing doesn't.

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

#204

Post by lrasinen »

vladar107 wrote: post #200

There's already a city in Finland getting free heating from a Microsoft data center. The problem isn't technical. It's that data centers and district heating grids rarely end up next to each other by accident.

Not yet, the Microsoft center is still in planning/construction.

But up north there's at least one city (Kajaani) on data center heat; details in another comment.

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

#205

Post by imtringued »

kayo_20211030 wrote: post #63
mattmanser wrote: post #62

Earlier quoted context omitted.

Speaking from a UK perspective global warming is now noticeable, hot days are hotter and there's more likely to be a heat wave, and that's changed in the last decade. I assume Germany is the same, many years ago really is different to today.

For sure. Everywhere. Even observationally, we just all know it's hotter, or wetter, or colder - it's all way more extreme in all dimensions.

Yeah early this year I've had the coldest winter in years and now the hottest summer in years.

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

#206

Post by JimDabell »

one33seven wrote: post #184
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…

The value of an AI data center in your area is negative, not near zero. Pollution, water use, heat, infrasound ( https://www.youtube.com/watch?v=_bP80DEAbuo ) and so much more... But at least we may get some cheap heat in the future

That infrasound video is nonsense:

https://blog.andymasley.com/p/contra-benn-jordan-data-center...

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

#207

Post by lrasinen »

amluto wrote: post #116
VorpalWay wrote: post #77

Earlier quoted context omitted.

You might (but probably not) be able to do district heating with this, but electricity generation is not going to be efficient. Heat is a very low grade form of energy, and you need a large differential to drive a turbine efficiently. If you cycle between 45 C and 55 C water temperature (as mentioned by the press release), you are only getting a 10 C delta. That isn't even enough for district heating, probably not ev…

> If you cycle between 45 C and 55 C water temperature (as mentioned by the press release), you are only getting a 10 C delta. You are calculating the wrong delta T. To heat a space, you need your working fluid to be warmer that the space you’re heating by an appropriate amount. 55°C is certainly on the cool side to heat a building, but it’s entirely workable with a high-area, highish-thermal-conductivity system. Her…

55 C might be enough to heat buildings but it's right on the edge where domestic hot water needs to be to kill Legionella. So traditional DH systems need to run hotter.

There low-temp/cold DH systems out there that rely on heatpumps in the buildings to extract the heat. Less losses in the network and you can even use them for cooling, but needs heat pumps everywhere.

In comparison, a traditional heat exhanger is pretty simple technology; just a hunk of metal with a valve.

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

#208

Post by samarthr1 »

prng2021 wrote: post #126

“That unlocks something beyond energy savings: the possibility of eliminating water consumption entirely.” They’ve made this claim numerous times in the article and I really don’t understand it. The building has tons of water being recirculated through it. That water came from somewhere in the surrounding natural world. How is that 0 water consumption?

I understood that to mean zero steady state water consumption?

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

#209

Post by JimDabell »

retrochameleon wrote: post #197
amluto wrote: post #29

Earlier quoted context omitted.

I’ve been to datacenters, but not the huuuge ones people seem to talk about in the context of AI. They are noisy inside (due to air cooling, which is largely avoided by the tech in the OP), but they’re entirely unremarkable outside compared to any other commercial or industrial building. Computers are not inherently loud, nor is power conversion. Power plants are all over, even in populated areas. They’re not so bad…

Look up Benn Jordan's video on datacenter infrasound. Just because you can't perceive the noise doesn't mean it's not there and it doesn't have an effect on the human body, especially over very long periods of time.

That infrasound video is nonsense:

https://blog.andymasley.com/p/contra-benn-jordan-data-center...

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

#210

Post by gooseh »

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.

But a larger delta-T makes it more efficient?
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