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How does the US use water?

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Re: How does the US use water?

#91

Post by FredPret »

Manuel_D wrote: post #88
FredPret wrote: post #78

Earlier quoted context omitted.

I don't think they're uneconomical. Fresh, clean water is astonishingly cheap; of course people are using it to grow almonds and alfalfa in the desert. Just charge people what the water is worth and they'll stop, or water companies will be able to afford much more treatment capacity. You have a point about sequestering CO2 molecules, but: a) I'm sure this will get cheaper over time, just like every other technology b…

While I do agree the hysteria around water use is unfounded, it's just patently false to say that fresh water cannot be wasted, pointing out that the molecule is just in a harder to access state is pedantry.

But the reason I hammer on about this point is precisely due to the hysteria. In the popular imagination, we spray x million gallons of water onto a golf course, and it just evaporates, never to be seen again. It is the alarmism that alarms me.

Re: How does the US use water?

#92

Post by rawgabbit »

gpm wrote: post #80
rawgabbit wrote: post #59

Earlier quoted context omitted.

I assumed only nuclear power plants need that much water for cooling. It is only an assumption. If I am wrong I am happy to be corrected.

I don't have numbers to quote at you, but I would assume not. Fundamentally coal, nuclear, and gas-boiler (but not gas-turbine) power plants work the same way - you heat up water until it boils, and run the steam through a turbine to turn that heat into mechanical energy. I.e. the "cooling" is also the electricity generation mechanism. As a result same amount of heat should result in the basically same amount of elec…

I was mentally referring to this article. It mentioned that natural gas plants only used one tenth that of coal. I assumed this is because natural gas plants are newer etc.

https://www.eia.gov/todayinenergy/detail.php?id=50698

      Natural gas-fired generation uses a more energy-efficient technology to produce electricity than coal and has a lower water withdrawal intensity than coal. Natural gas combined-cycle generation had an average water withdrawal intensity of 2,793 gal/MWh in 2020, compared with 21,406 gal/MWh for coal.

Re: How does the US use water?

#93

Post by jeffbee »

azemetre wrote: post #77
jeffbee wrote: post #29

Earlier quoted context omitted.

That's because it's a large industry and nobody lives there. This pattern appears all over the place. The paper mills in the pacific northwest consume large multiples of the water used by their little towns.

That's not the point, the question was whether an apartment building would use the same amount of water and clearly an apartment would consume substantially less water.

If you replace the area of that data center with apartments, as the question suggested, it would add half again to the local population, which could indeed use 30% of the city water.

Re: How does the US use water?

#94

Post by rufus_foreman »

adrr wrote: post #16
TMWNN wrote: post #4

I recently learned that Las Vegas recycles 100% of its drinking water.

Orange County California does the same. Injects treated wastewater back into the aquifer. Largest toilet to tap system in the world.

"Toilet to Tap" would be a great name for a California brewpub.

Re: How does the US use water?

#95

Post by rawgabbit »

Manuel_D wrote: post #66
rawgabbit wrote: post #11

It said 41% of the water used in the US is for thermo electric cooling. Albeit, it didn't break this down into saltwater vs freshwater. It also said the vast majority of this water usage is due to older plants that did not recirculate the water. The newer plants that recirculate the water only used a tiny fraction of water in comparison. So...if the US replaces all of its old nuclear power plants, we would free up al…

Note that water use is not the same as water consumption . If 100 gallons of water passes through a heat exchanger and 99 gallons go back into the river, only then 100 gallons were used but only 1 gallon was consumed . Thermoelectric cooling makes up a lot of water use, but on 1-2% of water consumption because most of the used water is returned: https://watercalculator.org/footprint/water-use-withdrawal-c... Furtherm…

Thanks. So the water of water consumed is by agriculture and “public use”.

Re: How does the US use water?

#96

Post by rawgabbit »

ethan_smith wrote: post #89
rawgabbit wrote: post #11

It said 41% of the water used in the US is for thermo electric cooling. Albeit, it didn't break this down into saltwater vs freshwater. It also said the vast majority of this water usage is due to older plants that did not recirculate the water. The newer plants that recirculate the water only used a tiny fraction of water in comparison. So...if the US replaces all of its old nuclear power plants, we would free up al…

Thermoelectric cooling's 41% includes all thermal plants (coal, gas, nuclear), and most of this water is withdrawn but returned to source, not consumed - so modernizing would reduce withdrawals but not free up that water for other consumptive uses.

Thanks.

Re: How does the US use water?

#97

Post by dmd »

recallingmemory wrote: post #32
Aurornis wrote: post #30

Earlier quoted context omitted.

It’s a great example of using large numbers without context to scare people. Say “6.4 billion gallons” in isolation and people will be horrified. Put it in context relative to something like alfalfa farming and it doesn’t even appear on the same scale.

Absolutely, not to mention the difficulty people have in grasping the difference between a billion and a trillion.

"You have a million dollars? Damn man you a regular Elon Musk or something"

Re: How does the US use water?

#98

Post by gpm »

rawgabbit wrote: post #92
gpm wrote: post #80

Earlier quoted context omitted.

I don't have numbers to quote at you, but I would assume not. Fundamentally coal, nuclear, and gas-boiler (but not gas-turbine) power plants work the same way - you heat up water until it boils, and run the steam through a turbine to turn that heat into mechanical energy. I.e. the "cooling" is also the electricity generation mechanism. As a result same amount of heat should result in the basically same amount of elec…

I was mentally referring to this article. It mentioned that natural gas plants only used one tenth that of coal. I assumed this is because natural gas plants are newer etc. https://www.eia.gov/todayinenergy/detail.php?id=50698 Natural gas-fired generation uses a more energy-efficient technology to produce electricity than coal and has a lower water withdrawal intensity than coal. Natural gas combined-cycle generation…

Yeah, that's the gas turbine thing. The first-stage (which generates the majority of the power) isn't boiling water, but extracting energy directly from pressure from burning the gas in a jet-engine like fashion.

The coal/nuclear like natural gas is what is labelled as "Steam Turbine" in the chart in this article: https://www.eia.gov/todayinenergy/detail.php?id=61444

Looks like it's already a small minority.

Re: How does the US use water?

#99

Post by azemetre »

jeffbee wrote: post #93
azemetre wrote: post #77

Earlier quoted context omitted.

That's not the point, the question was whether an apartment building would use the same amount of water and clearly an apartment would consume substantially less water.

If you replace the area of that data center with apartments, as the question suggested, it would add half again to the local population, which could indeed use 30% of the city water.

I'm not understanding the logic. You want to add more population to the city? That doesn't seem fair but I'll concede I may not understand the point you're trying to make.

Assuming that the population is the same in the city and you just move residents into an apartment complex. I don't understand how you would get the same water consumption, am I missing something? Evaporative cooling is extremely water heavy and these facilities also have the normal HVAC you'd expect. Everything just seems to point to more water usage not less.

Re: How does the US use water?

#100

Post by SapporoChris »

Aperocky wrote: post #84
dexterdog wrote: post #74

Earlier quoted context omitted.

The water that cools the datacenter is one minor ingredient in the process. For the cotton plant it is one of the few, critical ingredients.

How is it a minor ingredient if the data center will not work without it? No datacenter can operate normally without a cooling system.

A cooling system can operate without water.
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