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Comment by butvacuum | Hacker News Reader

Horrifically pessimistic numbers for PV (winter in maine with conversion efficencies half what they are now)... comes out to about a 50x50 mile square of panels to generate the entire USA's power demand from the most recent DOE numbers. Ignore that we can have wind, solar, and crops* in the same area. Turns out, btw, crops don't like high noon beating down on them. As a result we can reduce water usage and get nearly the same crop yield if part of the field is covered with panels- at least according to some studies.

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That isn't the whole story. At least some of these new datacenters are gigawatt class. That's multiple sq km of solar.

Water usage is also an issue. A continuous 1 gigawatt is enough to boil off 1.3 million liters per hour which over 24 hours equates to very roughly 90k residential users. If it isn't boiled but is instead returned lukewarm it will require many times that amount due to how large the heat of vaporization is. Compare to the entire state of Florida at "only" 23.5 million people.

did you move the goal post, or erect a new one? either way- residential use is penny ante in terms of water usage. So much so that comparing data center use to residential use without including industrial, commercial, and irrigation can only be in bad faith.

Particularly since usage reports typically present all the numbers in the same chart or grid.

The concern is resource usage. Water had been left out, so including it isn't shifting the goalposts given the context.

The comparison was intended for illustrative purposes. Residential usage provides something relatable and is the general standard for these sorts of discussions.

Even comparing to industrial most operations don't use anywhere near as much electricity or water. The new gigawatt class datacenters are in the same ballpark as aluminum smelters, but rather than melting metal they sink all that energy into water.

What? The water is not getting boiled off. Datacenters, for the most part, have closed liquid loop cooling systems. Electricity goes in, hot air and bits come out.

The old datacenters had. I don't think anyone is air cooling (radiator or otherwise) a gigawatt. Convert 1.3 million liters per hour from boiled water to air and you get an absurd number.

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