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A vision for the alleviation of water scarcity in the US Southwest

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Re: A vision for the alleviation of water scarcity in the US Southwest

#131

Post by sixstringtheory »

hnu123 wrote: post #97
solardev wrote: post #36

Earlier quoted context omitted.

It's a community of hackers passionate about the way things work. Picking it apart helps everyone understand the inputs and outputs of a system to understand how feasible it is, and what the tradeoffs are. What would you prefer, a generic "that's nice"? As far as I can tell, the author just kinda glossed over the brine situation. Some minerals can be sold, but his solution for the excess salt was just to turbulently…

[flagged]

This is some negging bs.

Current front page items include a paper on vector databases, an example of AI garbage that showed Amazon in a bad light, a quite in-depth treatment of “Trilinear Point Splatting for Real-Time Radiance Field Rendering” hosted on a PhD’s own github page, you know github, a huge gathering place for hackers to share their code with each other? An article criticizing Unity about banning an open source LGPL application, written by a developer of said open source product, introducing a competing platform to further decentralize the app store landscape, an article critical of Boeing, an article critical of Apple, a radical rocket design, bluetooth mesh networking, an open source python notebook project, an indie developer’s project to run stable diffusion in an iOS app instead of from some corporate server, an article on the ethics of immersive tech, an article on mysticism and empiricism, an article on epistemology…

Yeah, real dull business environment here. I’d totally rather go back to my training on peer performance reviews.

If you can’t find anything interesting on this site, it is a you problem.

"If you run into an asshole in the morning, you ran into an asshole. If you run into assholes all day, you're the asshole."

We’re all so sorry that you can’t just do whatever you want while unleashing the externalities on society at large. You want to hack, go do it in your basement where you can’t affect the rest of us. You want to engineer, you have to answer to more people than just your mom asking what you want for dinner.

Re: A vision for the alleviation of water scarcity in the US Southwest

#132

Post by adrianmonk »

warcher wrote: post #126
adrianmonk wrote: post #124

Earlier quoted context omitted.

It does matter, though. Suppose you need X amount of fresh water output per month. And suppose that for Y dollars, you can build a plant that supplies X if it runs 24 hours per day. If, instead, you can only run your plant 8 hours per day instead of 24, then you need to build a plant three times as big, which costs 3Y dollars. This is where batteries (or other energy storage) may become useful. If you can build them…

What I'm saying is that the freshwater reservoir is a totally free grid scale battery for a desal plant. No need to save it, just make fresh water while the sun shines and drink it whenever.

Energy storage would serve two purposes:

(1) Ensure you always have fresh water available since you're continuously producing it.

(2) Reduce the size of desalination plant you must build by allowing you to run it 24x7.

You're right that you can just store the fresh water, so batteries aren't needed for #1. But the article is talking about how to achieve #2.

Re: A vision for the alleviation of water scarcity in the US Southwest

#133

Post by tuatoru »

JohnMakin wrote: post #40
bilsbie wrote: post #23

Earlier quoted context omitted.

It sucks you guys home in on some weird issue for every promising technology. He literally addresses brine in the article.

He addresses brine, but not the waste products that come from brine, and only addresses it in one sentence: > The resulting depleted brine is piped back to the ocean where it is thoroughly mixed with sea water and discharged. This is not nearly as easy as this sentence implies.

Yes it is. We do it with urban wastewater in thousands of locations around the world. This is not a hard problem, nor is it expensive.

Re: A vision for the alleviation of water scarcity in the US Southwest

#134

Post by solardev »

hnu123 wrote: post #112
solardev wrote: post #100

Earlier quoted context omitted.

Well yes, that too. A mix of both, not sure of the percentages. Frankly I wish there were a better place for the hackers to congregate without the capitalists. But whatever, at least the discussion here is civil and interesting. Best place I've found since Slashdot of old.

[flagged]

Well, if you don't find them interesting, you don't have to be here? Many of us still do find value here.

Do you have other similar forums you recommend?

Re: A vision for the alleviation of water scarcity in the US Southwest

#135

Post by elmolino89 »

konschubert wrote: post #96
elmolino89 wrote: post #73

I am by no means a desalination expert, but pumping vast amount of a salty water 100+ kilometers (Pacific Coast) or from the Sea of Cortez (closer to 200kms) seems strange as compared to building the desalination plant on the shore and transfer the electricity generated in the desert. One can also replace some drinking or agricultural water used way closer to the coast in CA from the Colorado Basin with the newly des…

You are right. Power is easier to transport than water.

I have spend few years in San Diego doing hikes inland. There are decently sized mountains in the desert between say Borrego Springs and the coast. Not an optimal area to build a pipeline cheaply.

Pipe going along Colorado river should have less bumpy course but there is a biosfere reserve just on the top of Baja California. Not a good spot to suck giant volumes of sea water, even less so to construct a pipeline or heavens forbid dump the concentrated brine.

Re: A vision for the alleviation of water scarcity in the US Southwest

#136

Post by ianburrell »

hnu123 wrote: post #101

There's an abundance of freshwater in the east coast, northwest and midwest. Why not shift some of the exess water from the great lakes, east coast and northwest to southwest? Can't we pipeline the water to giant reservoirs in the sw or even carve extend tributaries from the missouri river or create canals down to the sw? It's not exactly rocket science.

Way, way too expensive. Pumping water east of the Rockies would use a ton power. Local desalination would cost way less. This plan is not feasible because it pumps water from Sea of Cortez to Salton Sea over 200 mi.

Re: A vision for the alleviation of water scarcity in the US Southwest

#137

Post by ianburrell »

drkevorkian wrote: post #114
bparsons wrote: post #83

The details might be a bit goofy, but this sort of large scale geoengineering project is going to be the only way that the SW is going to remain inhabitable. The American southwest has a couple big things going for it -- unlimited sunshine and an extraordinary amount of empty land. You can combine these things to create huge amounts of electricity which can be used to irrigate new farm land, power mines and build new…

Habitable? There is plenty of water for it to be habitable, residential use is a drop in the bucket compared with agricultural use. Without a technological solution, we'll have to scale back agriculture, but that's not a regional problem, since the market for food is an international one.

Also, we don't have to get all of the water from desalination. Southern California can use desalination, which makes sense to the ocean, short distances, and solar power. That frees up Colorado River water that Nevada and Arizona can use.

Desalination will probably never be worth it from agriculture, but agriculture should survive on the water they can access after people.

Re: A vision for the alleviation of water scarcity in the US Southwest

#138

Post by monkeynotes »

solardev wrote: post #76
jakderrida wrote: post #50

Earlier quoted context omitted.

[flagged]

Not the OP, but I think humans in general find it difficult to scale up. Whether in software or manufacturing or politics or environmental issues, we're much more equipped to deal with 1 or 10 of something than 100,000 or 1 trillion of it. At the end of the day we're still limited by our biology and brains, evolved for very different setting than the world we now live in. We try and we get by but by and large we're n…

Whether it's misanthropic or not is moot if it's just a plain fact.

Re: A vision for the alleviation of water scarcity in the US Southwest

#139

Post by solardev »

monkeynotes wrote: post #138
solardev wrote: post #76

Earlier quoted context omitted.

Not the OP, but I think humans in general find it difficult to scale up. Whether in software or manufacturing or politics or environmental issues, we're much more equipped to deal with 1 or 10 of something than 100,000 or 1 trillion of it. At the end of the day we're still limited by our biology and brains, evolved for very different setting than the world we now live in. We try and we get by but by and large we're n…

Whether it's misanthropic or not is moot if it's just a plain fact.

Yeah, true too.

Re: A vision for the alleviation of water scarcity in the US Southwest

#140

Post by amluto »

adrianmonk wrote: post #124
warcher wrote: post #115

Earlier quoted context omitted.

Batteries have proven extremely resistant to the scaling of solar panels. I would love to be wrong about this, but overwhelmingly people with an agenda just kind of hand-wave past grid scale energy storage problems that we have generations of evidence against being easily or cheaply solvable. The thing about this plan that I love though, is that who cares if the desal plant runs at night? Desalination can take all of…

It does matter, though. Suppose you need X amount of fresh water output per month. And suppose that for Y dollars, you can build a plant that supplies X if it runs 24 hours per day. If, instead, you can only run your plant 8 hours per day instead of 24, then you need to build a plant three times as big, which costs 3Y dollars. This is where batteries (or other energy storage) may become useful. If you can build them…

My question is: should it actually cost 3Y? Sure, if you take an off-the-shelf design and triple it, it will cost around three times as much.

But there should be at least some efficiencies that can be gained. For example, energy conversion is not cheap. Rather than building solar inverters that produce 480VAC and using 480VAC pumps or pump drives, what if the pumps ran on DC?

Or, for more fanciness, what if the pump drives were themselves the MPPTs? Have the solar panels arranged so they produce a sufficient voltage for the motor drive bus even at minimum output, and make the drivers smart enough to run the right number of pumps at the right power and to do so while tracking the maximum power point? That’s a lot of power electronics that could be avoided.

Also, if a plant is willing to store a day’s worth of seawater and brine, then the intake and discharge systems only need to be sized for maximum daily average flow, not peak sunshine flow.

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