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by prng2021 34 days ago
“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?
3 comments
dgacmu 34 days ago
As someone else noted - it's effectively zero compared to the water evaporated in evaporative chillers.

But it's still misleading. The major source of water use in datacenters, by _far_, is the water used in power generation. This improves PUE, which reduces power draw, but the savings are almost certainly under about 20% given that many modern datacenters already operate at a PUE of under 1.2. So if you're running on coal or gas, you're still consuming quite a bit of water indirectly.

Now that said again - the water consumption part of this equation is generally overhyped. The power draw is the problem, as are the really bad temporary hacks to the power problem (e.g., what x.ai is doing with "temporary" gas turbines).

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tylerjharden 33 days ago
Can you explain what PUE stands for? I am lost.
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dgacmu 33 days ago
Sorry! Power Usage Effectiveness. It's a measure of the overhead of delivering power to the servers (or motherboards, depending on how you measure it), taken to include all other datacenter power overheads: AC/cooling, UPS losses, and sometimes transformer/rectifier losses.

A PUE of 1.2 means that for every watt of power you're using in a server, you're using 1.2 watts drawn from the grid (approximately). Those extra 0.2 watts are being spent on cooling and other things.

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vkou 34 days ago
After filling the tanks once, subsequent draw would be zero. Most data centers currently use evaporative cooling - where they pull tons of water in, and then... Let it evaporate.

Imagine a residential building that reclaims and reprocesses and purifies 100% of all the water it uses. This would be dramatically more difficult and better than the status quo, and would be called 'net zero' by any sensible accounting method.

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Obviously, evaporative cooling is net-zero water use when accounted across the entire globe (the water falls as rain, somewhere, eventually), but it is net-negative for a local community.

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samarthr1 34 days ago
I understood that to mean zero steady state water consumption?
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