California City Considers Restarting Desalination Plant To Fight Drought 420
First time accepted submitter SaraLast (3619459) writes in with news about Santa Barbara considering the restart of its desalination plant. "This seaside city thought it had the perfect solution the last time California withered in a severe drought more than two decades ago: Tap the ocean to turn salty seawater to fresh water. The $34 million desalination plant was fired up for only three months and mothballed after a miracle soaking of rain. As the state again grapples with historic dryness, the city nicknamed the "American Riviera" has its eye on restarting the idled facility to hedge against current and future droughts. "We were so close to running out of water during the last drought. It was frightening," said Joshua Haggmark, interim water resources manager. "Desalination wasn't a crazy idea back then." Removing salt from ocean water is not a far-out idea, but it's no quick drought-relief option. It takes years of planning and overcoming red tape to launch a project. Santa Barbara is uniquely positioned with a desalination plant in storage. But getting it humming again won't be as simple as flipping a switch."
At some point... (Score:3)
....someone's going to figure out that the problem here is " It takes years of planning and overcoming red tape to launch a project. "
Seriously?
Why?
If the state simultaneously refuses to constrain growth within their water resources, and cannot GTFO of the way of communities *solving* the water resource limitations themselves, does anyone see there's a contradiction there?
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Because the state is the one who is going to pay for it. Desalination is very costly and inefficient. It can not be run as a profitable business.
Radiation! (Score:2)
I'm soooo looking forward to someone in California realizing that their seawater is connected to the seawater outside of Fukushima Daiichi ...
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1) It's unlikely there's significant amounts of radiation after having been diluted with the entire Pacific Ocean.
2) Even if their were, it would be removed during the evaporation process, as it's unlikely this plant is going to be operating at a temperature sufficient to boil heavy metals
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Precisely! :)
Re:Radiation! (Score:5, Insightful)
I'm soooo looking forward to someone in California realizing that their seawater is connected to the seawater outside of Fukushima Daiichi ...
LOL, Yea, I love this kind of thing. Just because we can MEASURE the radiation in something means that it is a deadly poison.. Never mind that the yearly exposure is an order of magnitude or two less than what you'd get say in one airplane trip... You are right though, there will be protests the day before they turn on the switch (after the money is spent) claiming it's "not too late!" .
You say RADIATION and the poor uninformed public run like scared sheep to put a stop to that deadly menace to society, science and medical experts aside.
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NSA and CIA aren't the first threat to freedom (Score:2)
And that, ladies and gentlemen, is the evidence of lack (if not outright absence) of freedom. Sure, the government collecting records of our communications is scary. But the real threat is that more and more things are considered a privilege to be granted — or withdrawn — by the Executive, rather than a right, which can only be taken away by the Judiciary.
When even a (smaller) government — with officials fighting red t
plenty of water from reverse osmosis (Score:2)
but it ain't cheap. What is amazing is one of these heavy duty reverse osmosis systems, I saw one on a small trailer where the hose in harbor water in New Orleans just after Katrina. That water had all kinds of horrible stuff from sewage to industrial chemicals, but the output was nice clean drinking water. On a large scale it can be very expensive and then what to do with the filter units. Also the energy to run these things. So you can get water, it's the cost penalty.
I say for starters don't use water
The West is pretty much fucked. (Score:2, Interesting)
Desal as power sink for "idle" wind/solar power? (Score:4, Interesting)
One of the challenges for renewables like wind/solar is being able to generate power when the grid doesn't need it.
Maybe instead of stopping the windmills they should keep them spinning but use desal plants as a power sink for the "excess" power. It's by and large free energy they wouldn't even generate; you might as well generate it and use it to do useful work.
It's debatable whether the excess energy could desal enough water to make a difference.
Positive feedback loop (Score:3)
Santa Barbara isn't like the rest of CA (Score:3)
Re:now I never looked into it (Score:5, Funny)
Now I never really looked into it, but it sounds easy. Too bad the people working on this aren't as smart as me.
Science is hard (Score:5, Informative)
It's that little bit about boiling the water. Converting water from liquid to gaseous phase (aka boiling) is energy intensive (read:expensive). To go from room temp water (we'll say 20C) to all of it vaporized and ready for condensation takes about 0.72kWh for each liter of water. So before you run the plant, pump the water, cool the condensate, and prep it for delivery, you've got that much energy going in. Even if you had no other costs, and you paid the lowest (tier 1) residential rates from So Cal Edison, you're looking at $0.36/gal for water. Add processing, markup, delivery...you're north of $1/gal, I'd bet.
Of course, that's why they don't generally use distillation, but even in your scenario the cost of "just boiling the water" adds up very, very quickly.
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Re:Science is hard (Score:5, Informative)
You may be unaware, but the density of solar radiation is only about 6 kWh per meter square per day. That means that each parabolic trench of a square meter is capable of producing only about 10 liters per day. You'd need 100 square meters to provide the water needs of a single ordinary house. And that's assuming 100% efficiency; it's more likely to be at least twice that and quite possibly an order of magnitude, by the time you've shipped it. Then you've got to clean up the gunk, and amortize in the costs of the setup.
I'm all for more solar powered stuff, but it's not the automatic, easy win we'd like it to be, even for something as simple as this. Heating water to the boiling point, only to recondense it a moment later, is expensive. I'm sure that clever design could reuse that heat and reduce the costs, but it's still going to be far from free.
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Yes, consider the fact that most energy produced is from steam power. Coal burning plants & nuclear power plants are just complex steam creators. It seems like they could be combined into both electric & water production plants.
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To go from room temp water (we'll say 20C) to all of it vaporized and ready for condensation takes about 0.72kWh for each liter of water.
True, but much of the heat used to raise the temperature and vaporize the water can be recovered and recycled. Distilling is still an expensive process though.
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Conveniently, a lot of energy is stored in that gaseous water which could be converted back into electricity [gizmodo.com].
Why would a distillation plant pay residential rates?
Re:now I never looked into it (Score:5, Informative)
To me all you need to do is boil water to strip the salt, you sell the salt and the water back.
The difficulty is not the ability to do it, it is that the energy requirements make it economically uncompetitive. Boiling that much water and then collecting the condensation generally takes a LOT of energy which is quite expensive in most cases. Places with a desert like climate and abundant energy resources (like the Middle East) can result in desalinization plants that are economically sensible but in much of the world it's just not competitive. Theoretically you could have a nuclear powered desalinization plant that might be economically competitive but I'm not aware that anyone has done this yet.
you sell the salt and the water back.
Doesn't work when it cost you more to get the salt and water than it costs to truck/pipe it in from elsewhere. Salt in this case is a byproduct but you wouldn't be able to sell it profitably or even on a breakeven basis given current prices in most places. Same with the water if it is being sold to farmers. It makes their crops economically uncompetitive with those from areas not experiencing drought.
Obviously it is more proccessing, and more expensive than getting just ground water or rain water because of that but how much more expensive can it really be?
Consult wikipedia [wikipedia.org] for a quick answer.
could it not be done in a way where we use the salt water in a new type of energy generating plant, that collects the steam and makes it usable?
There are waste heat desalinization plants being experimented with.
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The Saudis are planning to build out a lot of nuclear power stations over the next couple of decades which along with solar thermal power plants will be used to power desalination plants currently fuelled by oil and gas. Other Middle eastern nations
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The problem is scale.
Yeah but how much does it cost to boil water?
And you're not just talking boiling it, but boiling it away into steam. Get a big stock pot, fill it with water, put it on your stove, see how long it takes to boil away.
Even if we say it's just 10 minutes on the range to boil away 1L of water, how much water do you use in a day?
Even at $0.25 / L you're looking at a very expensive source for water when desalinization happens. Plus you have all sorts of nasty side effects from the increase i
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Some actual energy and costs figures are here:
http://ccows.csumb.edu/wiki/in... [csumb.edu]
(Concerns a different region in California, but has been put together well.)
In the political battle in Santa Cruz last year, a key contention was that the proposed carbon offsets were not a real benefit to the environment.
Re:now I never looked into it (Score:4, Informative)
As has been pointed out, desalination plants don't typically use distillation, they use reverse osmosis. That is to say that they use very high-pressure pumps to force the water through a membrane which rejects salt. Energy consumption is currently at about 3 kWh per cubic metre, although that's falling over time was membrane technology improves (the less pressure required, the lower the cost).
That works out to about 3 watt-hours per litre. Where I live, industrial power rates put that at $0.0001056 CAD per litre. Or $0.1056 CAD per cubic metre of water (thousand litres) if you prefer.
Obviously, if you live in a place that charges more for power (industrial power is $0.0352 per kWh here), that cost goes up.
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I never looked into it but I always hear how expensive it is to run these things. To me all you need to do is boil water to strip the salt, you sell the salt and the water back. Obviously it is more proccessing, and more expensive than getting just ground water or rain water because of that but how much more expensive can it really be? also, could it not be done in a way where we use the salt water in a new type of energy generating plant, that collects the steam and makes it usable?
Reverse osmosis is a whole lot cheaper, energy wise, than distillation. The original plant was of the Reverse Osmosis type.
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I never looked into it but I always hear how expensive it is to run these things?
In short, absurdly expensive. So expensive it became economically impractical after running for 3 month as the '92 El Nino made relatively cheap reservoir water available again. With the odds of a strong El Nino climbing this year it looks like we are set for a repeat of that expensive debacle.
Feast and famine of rainfall is a fact of life that politicians seem incapable of grasping. It has always been this way. Average and water-poor years followed by strong El Ninos, which reset the reservoirs and snowp
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Not economically, no. Steam plants typically cool the steam just enough to make it condense before sending it back to the boiler to become steam again. This conserves heat and thus the amount of fuel consumed per pound of steam delivered.
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How do you deal with everything else that gets on the ceiling, like the salt spray from the air? How do you guide this raft to efficiently use its time, while still keeping management costs below the sale price of the water (including government funding)? How do you build the ceiling in the first place, which must be cooled to support condensation, mechanically conducive to collection, large enough to make the raft practical, and small enough to keep the raft manageable? Once you've filled the raft with sev
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These should answer most of your questions:
https://en.wikipedia.org/wiki/... [wikipedia.org]
https://en.wikipedia.org/wiki/... [wikipedia.org]
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The system is inefficient for how much work is put into it versus the water output.
Ok, so that's for a hand-built survival system... perhaps not a good reference for a purpose-built system.
In 1952 the United States military developed a portable solar still ...a large inflatable 24-inch plastic ball that floats on the ocean... on a good day 2.5 US quarts (2.4 l) of fresh water could be produced. On an overcast day, 1.5 US quarts (1.4 l) was produced.
The plant in question produces 7500 acre-feet (2,400,000,000 US gallons) per year. That's the equivalent of 18 million of the spheres. If we assume that the barge would have similar efficiency (which it probably wouldn't, as there would be significant thermal loss to the ocean below, as opposed to the military's encapsulation design), we would require a sunlit area of approximately 8.1 billion square in
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In 2012, California received 88 cents in federal spending for every dollar paid in federal taxes. [wikipedia.org] If the state were greedy, that number would be over a dollar.
Idiots? Probably. Greedy? Probably not.
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So let me get this straight...
The Sahara, which has existed for a few thousand years, is a result of the commodities market, and the solution is to just pump water in from the Mediterranean, using the minute amount of usable energy extracted from wave action, with a machine that's big enough to supply water to the whole desert, yet cheap enough that there won't be a "disagreement over the price"?
Sounds simple enough.
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Re:now I never looked into it (Score:5, Informative)
I'm not trolling. I just don't think you understand the scale of the problem.
To give the entire Sahara 28 inches of rainfall (which is the low end of what Iowa gets annually), you need 5.4 billion acre feet of water. By mass, that's 67 times the total amount of oil produced since 1850*. If you think the water business is the problem now, just wait until you see the management for that size of operation.
So where exactly do we get these 15,000,000,000,000,000 pounds of water? We could drain half of Lake Superior, but you specified rain barrels. That makes the math easy. Cherrapunji is often regarded as the wettest place on Earth, recording 1,041.75 inches of rainfall in a calendar year, which is 37 times what Iowa gets. That means we'd only need to cover an area 1/37th the size of the Sahara to get enough water, assuming it all has the same rainfall as Cherrapunji. Our total rain-barrel area is then only about 95,000 square miles, which would cover about half the area of France.
I guess you're right: The problem is politics and business. No government or corporation wants to try to build a rain-barrel raft half the size of France (or larger, since it won't all receive 1000 inches of rainfall per year).
* Wolfram Alpha is great for perspective.
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Except that QE is the purchase of investment vehicles (bonds) that return their cost. You're right, though: You're back to your original point where you don't understand economics.
That does bring up a good question, however: What is the price of the water produced with these rain barrels?
If we want to pay back the production cost of one barge in a single productive year, each gallon of water must be sold for only $0.023. The US average price per gallon of water is $0.002, so to compete with the current US m
Re:now I never looked into it (Score:5, Informative)
Desalination plants don't boil water to filter the salt out. They use reverse osmosis, which typically requires about 3 kWh of electricity per cubic metre of water processed due to the very high pressure pumps required to force the water through the filters.
Distillation versus Reverse Osmosis (Score:5, Informative)
Desalination plants don't boil water to filter the salt out
Incorrect. Quite a few of them do boil the water. Some through vaccuum distillation [wikipedia.org] which lowers the energy requirements but it still is boiling the water. Reverse osmosis is the principle competitive technology to distillation methods but both exist.
Re:now I never looked into it (Score:5, Insightful)
Nice strawman, but... No.
No one (sane) considers resource shortages a "good" thing. Resource pressure, on the other hand, helps to prevent actual shortages.
When you have a free and unlimited open faucet, you use water for any old thing that comes to mind - Drinking, bathing, slip-n'-slides, washing the car, making rainbows with mist, growing a climate-inappropriate groundcover plant, whatever strikes your fancy.
When you have a $200/month water bill associated with that faucet, you damned well make sure it goes to the necessities, and you find a way to shower in under five minutes.
And when you get a ration of one gallon of water per day - You use it for drinking and cooking, period.
Conservationists "like" situation #2 solely because it prevents us from getting to #3. Unfortunately, we have, historically, artificially created the appearance of situation #1 even in the middle of a frickin' desert thanks to activities like draining the Colorado river dry (and the resulting downstream environmental disaster, as well as not-so-slowly depleting continental aquifers that take millennia to refill (ask Florida what happens when those get too low).
In a universe where you can really make infinite energy and infinite water and infinite food - Waste all you want! But in our universe, TANSTAAFL.
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The hilarious part about the situation is the amount of overlap between conserv
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we better double down with even more micromanagement by implementing rationing so that everybody will stop using as much of the resource that we forcefully made too inexpensive."
Such as low-flow toilets. Don't get me wrong, my *modern* low flow flushes better than the original high-flow from the '70s(estimated), but it took a while to get there and you need to do your research.
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The hilarious part is conservatives who don't understand that the eeeeeevil regulations are less expensive to comply with than accepting what the market rate would be with no intervention.
Re:now I never looked into it (Score:4, Insightful)
Re:now I never looked into it (Score:4, Insightful)
Well if you have the choice between dying of thirst or paying $80 for a cubic yard, you'd probably pay the $80.
A cubic yard is A LOT of water. You could live for some time off of that.
And, probably at that cost it makes sense for people to bring in water by the tanker truck, pushing prices down.
The key is what you're using it for. If you just want something to drink, $80 per cubic yard is quite all right. If you want to take a desert and turn it lush and green, it's quite expensive.
Seems to me people should look at usage case more than anything else.
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"You could live for some time off of that."
No you can't, it's just over 200 gallons.
Unless by some time you mean about a week. You need to drink 1/2 gallon a day alone.
Bath: 40 gallons
Shower: 2.5 gallons per minute
Old showerheads may use 4 gal/min whereas newer low-flow showerheads use about 2.
Teeth brushing: 1 gallon
Depends on if you let the water run while brushing
Hands/face washing: 1 gallon
Face/leg shaving: 1 gallon
Depends on if you let the water run while shaving.
Dishwasher: 20 gallons/load
New energy-e
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No you can't, it's just over 200 gallons. Unless by some time you mean about a week. You need to drink 1/2 gallon a day alone.
By my calculations, 1/2 gallon a day means 200 gallons would last 400 days. More than a year. But, as you point out, there are other uses.
To put back some of the context, the person you replied to said: "Well if you have the choice between dying of thirst or paying $80 for a cubic yard, you'd probably pay the $80."
Teeth brushing: 1 gallon
If it takes you more than a cupful of water to brush your teeth, you are wasteful and Darwin says you will not survive. But you don't need to brush your teeth to keep from dying of thirst.
Face/leg shaving: 1 gallon
I'm
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I wonder how much energy is spent doing reverse osmosis desalination. Distillation is very expensive, so even pumping at high pressure will be a lot cheaper in terms of energy than boiling large quantities of water to have it condense somewhere else.
As for the barge mentioned, I wonder if coupling a reverse osmosis plant with a reactor (the US Navy has perfected smaller marine reactors for decades) might just be the ticket. However, I don't know how it would scale to the size needed for a thirsty desert r
Re:California = 1D10T Errors (Score:5, Informative)
Agriculture in the southwest (i.e. in the desert) is being killed by the lack of rainfall, which seems to have caught everyone by surprise. They're idiots first, farmers second.
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To put a partisan twist on this: The urban areas are the heavily democratic areas. The desert farmers tend to be GOP supporters. Who are the real welfare queens? See also: Bundy.
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>Farmers in the desert use about 20 times as much water as California urbanites.
Not quite. 80% is ag, 10% residential, 10% industrial.
In exchange, California earns about $17B from farms just in the San Joaquin, and supplies half the fruit in the nation.
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Anyway, California's gross state product is right around $2T, which suggests that those farms in the San Joaquin account for less than one percent of California's economy. It's a rounding error. Any economic argument is bound to fail here, as agriculture is virtually meaningless in this
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"while burning through resources at an unsustainable rate, is going to make the concept of money look like a complete fraud, within the next generation.
haha, there has been a douche bag making that claim every generation since the dawn of civilization.
Re:California = 1D10T Errors (Score:4, Informative)
Why can't food be grown in the Great Plains instead of the Mojave Desert?
It is grown there. However we're draining a lot of the aquifers in the Great Plains too since we plant crops like corn that use a LOT of water.
Re:California = 1D10T Errors (Score:4, Interesting)
eehhhhhhh. Sorta.
The western halves of Nebraska, the Dakotas and Kansas are all half-way to being deserts with rolling sand dunes and all. They need irrigation to support crops. Otherwise they're just grazing land. And not great at that either.
The Ogallala aquifer [wikipedia.org] which happens to be right in that area is indeed shrinking and it's a worry. Conservationists are like "OMG WTF!? that took thousands of years to accumulate" and farmers are like "It's been making my family MONEY for decades, we aint' stoppin". It's an issue for a sizable strip of land, but it most certainly doesn't apply to the majority of the "Great Plains".
The eastern half of those states, all the way to the Appalachian mountains, are plenty wet to support crops without the need of irrigation. Iowa has a "thriving" wine industry in the northeast in a strip of land that avoided being glaicered way back when so it's "weird" by our standards. And there are plenty of apple orchards. Johnny Appleseed is still legendary around here. But certain crops simply need a different climate. You're not going to have a... uh... banana industry in Minnesota.
All in all the USA has a fantastic piece of land for agriculture use and we could grow enough food to end world hunger. But getting it from the fields to hungry mouths has some logistical issues and so we grow feed corn to feed our cattle just so it tastes better. If we every really wanted to be super-dicks to the rest of the world. We'd unleash our capabilities, flood the markets with cheap food for a decade or until everyone else's agriculture industries collapsed and then simply stop making shipments. The Arab spring started with food riots.
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I hope you are ready when the population of southern California moves to where the water is. Don't worry, they will bring some "cool" with them. It will have to be an improvement.
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*sigh* - time to start building a fence and putting in machine-gun emplacements at the Oregon border...
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Aquifers in Minnesota aren't doing all that well (no pun intended) either. My family home is on White Bear Lake, which has become something of a cautionary tale [wblra.org] for careless groundwater pumping combined with wetland drainage in order to make $millions for developers and then shaft the people who've lived there for generations.
Re:California = 1D10T Errors (Score:5, Insightful)
> Rather, it is all about killing agriculture in the southwest to free up more water for California urbanites.
Agriculture uses about 70%, with industry using 20% and urban populations using 10% of the water. Agriculture, you know, that stuff you eat from those greedy bastards in California.
> Nevada rancher stand off...
Bullshit. It's about some welfare rancher not paying his grazing fee's. Pure and simple. He has no intellectual or legal argument, so he is whipping up the dummies over on Fox News to call out the Tea Party morons to protest his desire to rip off the Tax Payers.
Don't build in the desert (Score:2)
Agriculture uses about 70%, with industry using 20% and urban populations using 10% of the water. Agriculture, you know, that stuff you eat from those greedy bastards in California.
Much of the Central Valley in California is really a semi-arid desert [wikipedia.org]. Farm in a desert and it should not be shocking to anyone that you'll run into water shortages sooner or later.
Plus a non-trivial amount of water that could be used for farming is diverted to places like Las Vegas that simply should never have been built in the first place. You don't build a major metropolitan area in the middle of a desert unless you have no alternatives. And you certainly don't put swimming pools there. I've ever he
Re:California = 1D10T Errors (Score:5, Insightful)
Since when does RUNNING A FUNCTIONAL RANCH WITH YOUR OWN HANDS count as "welfare" on this planet?
When you're doing it on somebody else's land without compensating them?
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This should of been done 50 years ago. Various California water districts have been doing it for quite some time: http://www.acwd.org/index.aspx... [acwd.org] Just not on large scales.
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State of Colorado should halt the river until California dedicates funds toward this.
Riiight. Shut down the Hoover Dam and destroy the ecosystem of the Colorado river to teach California a lesson.
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Removing salt from ocean water is a big thing to set up, but don't forget that in addition to getting drinking water, you also get electric power out of the operation as well.
Thermodynamics much there?
Let me guess, you have a source of free energy too..
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Removing salt from ocean water is a big thing to set up, but don't forget that in addition to getting drinking water, you also get electric power out of the operation as well.
Actually this isn't as off the mark as it seems to be. A nuclear power plant could double as a desalinization plant. But no one seems to like nuclear power plants.
Re:And with that yoiu get POWER! (Score:4, Funny)
Re:And with that yoiu get POWER! (Score:5, Interesting)
No? It's exactly the reverse. This takes *HUGE* amounts of energy.
Electricity is one form of energy used to power desalinization but certainly not the only form. But you are correct in that the use of electricity to desalinate is not very efficient. A focused solar lens array much like the ones used in solar electric production would be more efficient AND the resulting steam could actually be used to produce electricity as a byproduct. Not enough to be considered an electric generation facility but something is better than nothing.
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Modern desalination normally doesn't work via distillation. It usually works by forcing seawater through a semi-permeable membrane.
It's cheaper on energy consumption, but you need to run pumps to do it.
That being said, solar powered distillation processes would probably work best on small scales.
Re:And with that yoiu get POWER! (Score:5, Informative)
Their mothballed desalination plant won't be a reverse osmosis system. It will be an older flash distillation plant.
Probably steam powered. I ran and supervised the operation of 2 multi-stage 100,000 gallon per day flash distillation plants in the Navy. They have very few moving parts and were very reliable. They just took a ton of steam to operate. Steam for the ejectors that pulled the vacuum, and steam for the heating elements. Lots of electricity for the pumps.
But they are talking about a plant that can produce millions of gallons per day of fresh water. It will be very clean and soft too. Expect 0 hardness on the output. They probably will be adding minerals so the output has good flavor.
Re:And with that yoiu get POWER! (Score:5, Informative)
Re:And with that yoiu get POWER! (Score:5, Informative)
I guess the initial costs might be quite a big higher than just getting a pump and a semi-permeable membrane.
It takes an average of 3kwh to desalinate 1 m^3 of water via reverse osmosis. Per this report [worldwaterweek.org] it's 4-12 kwh of thermal energy to distill 1 m^3, plus 1.5-3.5 kwh of electricity.
If we figure on 10 kwh of thermal and we're setting stuff up so that we're down near 1.5 kwh of electric*, then consult a solar map [nrel.gov], we're looking at needing 2-3 m^2 of collector per m^3 of production a day(at 90% or so efficiency), and it only cuts electric costs in half.
That's 264 gallons of water/day, roughly enough for 2.5 people [wikipedia.org]. Household useage, not commercial or industrial.
Please note that these are using near optimal assumptions, I wouldn't be surprised if you need 2-10 times as much collector as what I've estimated.
*Pumping and such.
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For goodness sake;
Just spray the damned water in a wind tunnel, use a baffle filter to catch salt crystals, then re-condense using a venturi.
Evaporation is a factor of ambient temperature, pressure, and surface area. Meddle with any one of those three and you alter the vapor point of any liquid.
This is not hard, but people like to act like it is.
(For the imaginatively impaired, here's what you do:)
1) spray the raw sea water through a tiny misting nozzel inside a wind tunnel that blows up a vertical shaft w
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Desalination is usually done by reverse osmosis. You need a pump of some description to do that. A solar array could provide the electricity to run the pump or power some sort of steam engine.
Re:And with that yoiu get POWER! (Score:5, Interesting)
... or you use pumps to pressurize a bunch of salt water and use a membrane to filter out the salt. Again pressurizing the water consumes a lot of energy.
Couldn't you just drop a container into the ocean, one with only two openings - one with your membrane for salt water in, the other opening for desalinated water out? The deeper you put it, the more pressure outside the container that pushes the salt water through your membrane. Then you could use a low power pump to slowly remove the clean water through a hose attached to the other opening.
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As soon as the pressure equalizes between the two sides of the membrane the flow of water will stop. Your pump will have to do all the work to pull the water through the membrane at the point. It's now also going to have to fight gravity to pump the water from the depths of the ocean.
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How is that any different from a groundwater well? How are those cost effective and is method isn't?
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Much WISER would be to deny frackers the CLEAN POTABLE WATER they pump deep into oil fields to get their 1 barrel of oil per 10 barrels wasted water.
1) I sincerely doubt the oil companies use the same water that you get from the tap to do that.
2) Southern California is a semi-desert anyway... always has been, always will be (well, within the next few centuries, anyway).
3) If they hadn't been so busy diverting existing water to save some obscure and hyper-local species of fish...
Don't build/farm in a desert (Score:3)
2) Southern California is a semi-desert anyway... always has been, always will be (well, within the next few centuries, anyway).3) If they hadn't been so busy diverting existing water to save some obscure and hyper-local species of fish...
These two arguments contradict one another. If it's a desert then realistically they shouldn't have been diverting the water that said fish depends on in the first place. It only became an issue because water was diverted that shouldn't have been. You don't build stuff or farm in a desert when you don't have to. Las Vegas and Phoenix should not exist in anything close to their current form.
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Well, well, well. What have we here?
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There is no link between water pumped into the ground for extraction and drinking supply. None What So Ever.
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Re: (Score:3, Interesting)
They might also ask Northern California to perhaps stop shipping a whole bunch of water to China in the form of really cheap Alfalfa..
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Much WISER would be to deny frackers the CLEAN POTABLE WATER they pump deep into oil fields to get their 1 barrel of oil per 10 barrels wasted water.
Um... The amount of potable water used by frackers is such a low fraction of available water that this is almost laughable. There is many times more water wasted in a day because people won't fix their leaky toilets than the frackers use in a whole year.
If your goal is to save water, I suggest you outlaw watering grass using sprinklers that spray water. Mandate drip irrigation and make sure people are maintaining their plumbing properly. You got to start where the waste is the biggest, or your efforts ar
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Mandate drip irrigation and make sure people are maintaining their plumbing properly.
That's easy to fix : put water meters at every house and make people pay per-gallon. You'll see people fixing their plumbing the day right after they receive the first bill
Re:A drop in the bucket. (Score:5, Insightful)
Much WISER would be to deny frackers the CLEAN POTABLE WATER they pump deep into oil fields to get their 1 barrel of oil per 10 barrels wasted water.
That barrel of oil is worth $100. The ten barrels of water were worth about $1. A better idea would be to get the government out of the business of "picking winners" by micromanaging the allocation of water through idiotic subsidies that result in tens of thousands of acres or rice growing in the desert. California doesn't have a shortage of water, we just have an excess of stupid policies.
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That would be hoprrid.
That means some rich guy will dictate who gets water. What's that? CA votes dem? well, no water for you.
Re:A drop in the bucket. (Score:4, Informative)
That means some rich guy will dictate who gets water.
Under the current system, rich farmers get subsidized water, while poor people in the cities pay high rates to fund those subsidies. It is almost inconceivable that any market based system could be more unfair than the current system designed by politicians.
What's that? CA votes dem? well, no water for you.
California as a whole votes Dem. Most of the Central Valley, which receives the water subsidies, votes Rep.
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rich farmers? I have never heard of a rich farmer. Either the farmer makes that season or not. Farming is a lot like the lottery on if your crops grow or not.
You obviously never heard of most of the companies that you buy your food from, then. The financial interests behind the farms are quite well-off. Heck, they and others in the industry paid billions in fines/judgments just over the lysine price-fixing scandal, and they're still in business...
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That barrel of oil is worth $100. The ten barrels of water were worth about $1.
All hail the almighty dollar!
When the well dries, you shall drink pennies!
When the food does not grow, you shall eat quarters!
When the air becomes polluted, you shall breathe stocks!
Re:A drop in the bucket. (Score:5, Informative)
So what you are objecting to the the Practice of Water Rights
Water Rights are a legal principle, not Federal Micromanagement. The water belongs to the person with the oldest rights to it first. Need isn't part of the equation.
The person who's water rights were established in 1849 have priority to the person who's water rights were established in 1999.
First come first served. Water Rights are inheritable and sellable. Those farmers have water rights that are older than the residents in the Cities. That is why they get first dibs. Not because they are propped up by the Federal Government. But because the process of water rights was established by Common Law, and supported by California and Federal Courts.
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Farmers in California's San Joaquin depend on government-provided water. The federal government built aqueducts and channels and so it can control water allocation.
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False, it is False. Completely and utterly False. Neither of you seems to understand what the word 'drught' means. Look it up.
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Unless you can demonstrate that the oil companies are hauling water from Santa Barbara to frack wells in other parts of the country, I don't see how this is relevant.
Besides, I think what you are describing is an oil recovery technique, not fracking. There is a process were water/steam is injected into old wells to try and recover more oil/gas, but it has little relationship to hydraulic fracturing
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They are using the same idea this time. Spending millions of dollars on a desalination plant will cause droughts to end.
Re:It's because I moved from California. (Score:4, Funny)
I could always predict when it would rain when I lived in Los Angeles. It was always the day I decided I would go to the beach.
So PLEASE move back to LA and plan to spend your first month on the beach...
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With that logic... why don't we drink salt water... there are oceans filled with that stuff...
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They're just throwing the stuff down the drain anyway.
Not an exact replacement, but I'm sure there would be issues with putting tons of salt water into the environment. I'm sure a fracking fluid spill made with salt water would be a SERIOUS environmental issue, where using fresh water it would not be an issue at all. Then the corrosive nature of salt water is likely to be a problem with the equipment. So, IMHO, your idea seems stupid at first blush.
Not to mention that fracking uses such a small fraction of potable water that it makes such regulations worth
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We learned from Hurricane Sandy that salt water on land isn't an environmental disaster in terms of its impact on vegetation. Most areas flooded experienced little effect on local vegetation and I should know, I live in south Queens (not effected by Sandy though, I am north of the Belt Parkway.) A few plants and trees died but that was about it. Everyone still has green lawns and plenty of trees. The bigger issue was with oil and and fuel getting washed out of cars and into the ground along with mold concer