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How does the US use water?

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Re: How does the US use water?

#101

Post by Manuel_D »

rawgabbit wrote: post #95
Manuel_D wrote: post #66

Earlier quoted context omitted.

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”.

More importantly, though, is that agricultural water is mostly consumption. That water is either evaporated or absorbed by plants.

By contrast, the overwhelming majority of water used by thermoelectric plants is not consumed. Electricity generation amounts to 1-2% of water consumption. There's hardly any water to be saved by changing power generation.

Re: How does the US use water?

#102

Post by dlcarrier »

gonzalohm wrote: post #28
lxe wrote: post #13

> Average per-capita domestic water use in the US is 82 gallons per day. By comparison, German homes use around 33 gallons per person per day, UK homes use around 37 gallons, and French homes use around 39 gallons. I want to know way more information about these figures... like, are there significant outliers? Drastically different usage profiles?

One thing that shocks me as an immigrant from Europe to the US is toilets. I have not seen a single one that has the two buttons, one for pee and one for the other stuff. Every time I use the toilet it uses 1.6 gallons. 6 liters... I think in my home country more than 90% of home toilets are the "low water usage one" (with 3 and 6 liters buttons) And that's only the start, I noticed that people just don't care about…

The toilet flushing thing is performative. Even if toilet water usage were enough to be worth caring about, dual flush toilets use more water over the lifetime of the toilet, because the more complex designs have a higher failure rate: https://www.theguardian.com/environment/2020/sep/29/dual-flu...

Also, in about half of the country, aquifers replenish as fast as they are used, so there's no point in regulating their use. The largest concern is usually whether or not the well is contaminated.

Re: How does the US use water?

#103

Post by dlcarrier »

widforss wrote: post #15
lxe wrote: post #13

> Average per-capita domestic water use in the US is 82 gallons per day. By comparison, German homes use around 33 gallons per person per day, UK homes use around 37 gallons, and French homes use around 39 gallons. I want to know way more information about these figures... like, are there significant outliers? Drastically different usage profiles?

I recently looked up whether it would be worth it to me to install a water meter instead of paying a flat-rate. Apparently the flat rate is calculated on a consumption of avout half a cubic meter per day. But, without a water meter, I can only guess if my consumption is more or less than that. My guess is that it's considerably less though.

I live in California, where half of the state is a desert half is a rainforest. The politicians here like to think that everyone lives in urban desert cities built on fault lines next to pyrophytic forests, so our regulations assume that every household needs earthquake proofing, fire proofing, thick insulation, and major urban planning.

I live in an area where pretty much non of those things matter, but one of the regulations that stands out the most is that the water everywhere has to be metered, even though the reserviour near me regularly has to be drained, because it's to full to make it through the wet season.

My water districts solution was to set the price per unit of water at cost, so I pay $40/mo for insfrastructure, and a dollar or two for water. If I quadrupled my water consumption, I wouldn't even notice the price change. I actually pay more to service the meters than I pay for water.

Re: How does the US use water?

#104

Post by dlcarrier »

Aurornis wrote: post #36
bob1029 wrote: post #2

> Water in the US is generally both widely available and inexpensive: my monthly water bill is roughly 5% of the cost of my monthly electricity bill, and the service is far more reliable. In my experience with municipal utility districts, the reliability of the water supply is typically not much better than the local power grid. The sewage lift stations seem to have the highest quality generator arrangements.

> In my experience with municipal utility districts, the reliability of the water supply is typically not much better than the local power grid. Both of these services have been phenomenally reliable everywhere I’ve lived in the United States. The only exception was in a town where we’d get ice storms once a year that would bring trees down on top of power lines, but it was shocking how quickly a truck would show up…

At least from what I've seen in my area, interruptions in water service don't result in a lack of pressure or flow, they result in contamination, and the water districts have to issue boil water orders. It's not a problem you would notice, and if you don't pay attention to local news, you might just end up drinking contaminated water.

Re: How does the US use water?

#105

Post by dlcarrier »

rawgabbit wrote: post #59
gpm wrote: post #12

Earlier quoted context omitted.

How did you go from "thermoelectric" to "nuclear"? The US has nearly as much coal power as nuclear power, and significantly more natural gas than nuclear.

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.

Pretty much every power plant heats water to steam, then uses steam turbines to generate power. This is also how nuclear submarines and arcraft carriers work.

We never left the steampunk era.

Re: How does the US use water?

#106

Post by MisterMower »

gonzalohm wrote: post #28
lxe wrote: post #13

> Average per-capita domestic water use in the US is 82 gallons per day. By comparison, German homes use around 33 gallons per person per day, UK homes use around 37 gallons, and French homes use around 39 gallons. I want to know way more information about these figures... like, are there significant outliers? Drastically different usage profiles?

One thing that shocks me as an immigrant from Europe to the US is toilets. I have not seen a single one that has the two buttons, one for pee and one for the other stuff. Every time I use the toilet it uses 1.6 gallons. 6 liters... I think in my home country more than 90% of home toilets are the "low water usage one" (with 3 and 6 liters buttons) And that's only the start, I noticed that people just don't care about…

Say every single one of the 330 million people in America flushes a toilet five times a day, every day of the year.

That’s still less than a cubic mile of water. Lake Mead, by comparison, has a volume of 7 cubic miles. Every American could go back to using outhouses and the water savings wouldn’t even be noticeable.

People are not very good at visualizing this stuff. The volumes involved are hard to grasp.

Or think of it this way: if you personally saved all that water by using an outhouse, it would amount to less than 300 gallons a month. My water bill doesn’t even show usage at a resolution high enough to see those savings. I’m billed per 1,000 gallons.

If the water company doesn’t care enough to track it and charge me for it, it’s noise.

Re: How does the US use water?

#107

Post by nine_k »

SapporoChris wrote: post #100
Aperocky wrote: post #84

Earlier quoted context omitted.

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.

This would require a much larger area, because servers could not be mounted so densely. Air cooling can't achieve the same amount of heat transferred per unit volume as water cooling. Water has uniquely high specific heat.

Re: How does the US use water?

#108

Post by dlcarrier »

lxe wrote: post #13

> Average per-capita domestic water use in the US is 82 gallons per day. By comparison, German homes use around 33 gallons per person per day, UK homes use around 37 gallons, and French homes use around 39 gallons. I want to know way more information about these figures... like, are there significant outliers? Drastically different usage profiles?

Agrigulture uses more water than households, but accounts for 0% of the population, making per capita usage a worthless metric.

All this does is reflect that Germany imports agriculture, while the US exports it.

Re: How does the US use water?

#109

Post by wombatpm »

FredPret wrote: post #50
adrr wrote: post #19

Earlier quoted context omitted.

Biggest alarmist is movement against Nestle using water for bottled water in California. They don’t even use as much as an average golf course. How much water is wasted on golf courses in these arid regions? Or growing water intensive crops like alfalfa that isn’t even directly used to feed people.

> How much water is wasted on golf courses... Zero. You can't waste water, it goes in a cycle. I mean unless you transport it off-planet. You can waste the energy you spent cleaning it and pumping it around. But between nuclear and solar we ought to have an overabundance of that. In a market economy, if it becomes "economically infeasible" to purify used water, the price goes up slightly, and suddenly it makes a lot…

Water used for nuclear reactor cooling can only be returned to the environment if its temperature is within 0.5 deg F of the local source temperature. I live near a facility that is on the river with several man made cooling lakes. During the winter, there is constant fog and ice by the roads. So much so, that the road to the facility itself has covered bridge crossing one of the lakes.

During drought, the capacity of the plant is reduced due to lack of cooling capacity.

And remember, the reactor is used to generate high pressure steam which produces electricity, hot water and low grade steam. Even with high efficiency gas turbines and heat integration, there is a significant amount of steam that needs to be condensed before it can be feed back into the reactor.

Re: How does the US use water?

#110

Post by gpm »

dlcarrier wrote: post #105
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.

Pretty much every power plant heats water to steam, then uses steam turbines to generate power. This is also how nuclear submarines and arcraft carriers work. We never left the steampunk era.

We're leaving it now, the majority of new energy capacity is now solar, and not steam based (>70% in 2024). And a non-trivial chunk of the remainder is wind (also not steam based).
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