What's the reason we can't use heat pumps here to turn that waste heat back into electricity?
45°C cooling design cuts data center water use to near zero
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Re: 45°C cooling design cuts data center water use to near zero
#232> 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.
Waste heat from these things is negligible compared to the sun heat. I know people love to hate on these things, but come on...
Re: 45°C cooling design cuts data center water use to near zero
#233Earlier quoted context omitted.
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.
Apparently SuperMicro also has an existing solution. They are stating very similar numbers: https://www.supermicro.com/en/solutions/liquid-cooling
Re: 45°C cooling design cuts data center water use to near zero
#234Earlier quoted context omitted.
45 is the cool temp so they could send the community a higher temp water to their heat exchanger? Then 45 or below is sent back on the return.
Yes, but the heat will still likely need boosting by about a further 10 degrees either at the source or end user. DC inlet is 45°C, outlet is 55°C assuming a 10°C ΔT. By the time that's travelled 500m–1km through pipework you've lost a few degrees, so you're arriving at the HIU at maybe 50–52°C. The home radiator circuit then takes that down by around say 12°C, returning ~38°C. Factor in pipe losses on the return leg…
> By the time that's travelled 500m–1km through pipework you've lost a few degrees
you'd be surprised. If you have high flow, and the pipes are insulated and underground, then after about a week the temperature drop isn't that much. You do have heat losses, but if you have a high enough continuos flow and a big enough pipe, then it'll be low enough to not worry about, especially if the aim is heat shedding rather than efficiency.
My old flat was powered by both the 1970s boilers across the way, and more recently the massive south london incinerator. The pipe cross section was I think 40cm and at peak carried ~3-5 Megawatts of heat. I think it operated at 150c, but that could be me misremembering (this is the later version of the network: https://www.burohappold.com/projects/veolia-southwark-2-0-he... for the councils is they get a maintained heater network, which is much cheaper than doing it themselves (even more now with gas being so expensive) the power station gets to charge for a waste product and it doubles their on paper efficiency, its a win win.)
Re: 45°C cooling design cuts data center water use to near zero
#235What's the reason we can't use heat pumps here to turn that waste heat back into electricity?
Too little thermal gradient.
What you could do is to use a heat pump to spend a little electricity and turn the waste heat to hot water usable for heating (winter).
Re: 45°C cooling design cuts data center water use to near zero
#236Earlier quoted context omitted.
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.
If I am not mistaken, Bull's warm water cooling requires water at ~30°C, so 45°C is still an improvement.
Re: 45°C cooling design cuts data center water use to near zero
#237Increasing the cooling setpoint of the system isn't exactly a new concept, nor is data centre scale water cooling.
Computers can run hot and not throttle.
Water is better at moving heat than air.
Temperature delta above ambient increase the amount of heat that can be removed, with less mechanical assistance.
How exactly is any of this news.
Re: 45°C cooling design cuts data center water use to near zero
#238This 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…
> 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.
That means is called property taxes. Datacenters pay a lot of them, and in Loudon county specifically residential property taxes have fallen as a result.
Re: 45°C cooling design cuts data center water use to near zero
#239Earlier quoted context omitted.
Yes, but the heat will still likely need boosting by about a further 10 degrees either at the source or end user. DC inlet is 45°C, outlet is 55°C assuming a 10°C ΔT. By the time that's travelled 500m–1km through pipework you've lost a few degrees, so you're arriving at the HIU at maybe 50–52°C. The home radiator circuit then takes that down by around say 12°C, returning ~38°C. Factor in pipe losses on the return leg…
> By the time that's travelled 500m–1km through pipework you've lost a few degrees you'd be surprised. If you have high flow, and the pipes are insulated and underground, then after about a week the temperature drop isn't that much. You do have heat losses, but if you have a high enough continuos flow and a big enough pipe, then it'll be low enough to not worry about, especially if the aim is heat shedding rather tha…
Yeah, I mean it does depend on the pipework and season/geography for sure. I was simplifying a bit in that a part of the 'distribution' losses are in the plate heat exchanger as you convert from the "IT" loop to the "district heating" loop. The numbers are roughly right, potentially slightly worse in deep winter when it matters the most.