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California City Considers Restarting Desalination Plant To Fight Drought
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."
Now I never really looked into it, but it sounds easy. Too bad the people working on this aren't as smart as me.
Farmers in the desert use about 20 times as much water as California urbanites.
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.
Chuuch. Preach. Tabernacle.
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.
Is it just my observation, or are there way too many stupid people in the world?
> 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.
Linux O Muerte!
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 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.
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.
They honestly see resource shortages as a good thing, because the modern technological lifestyle is inherently evil.
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.
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.
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.
"A person is smart. People are dumb, panicky dangerous animals and you know it." - K
... 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.
A recursive sig
Can impart wisdom and truth
Call proc signature()
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.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
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?
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 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.
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.
You do not have a moral or legal right to do absolutely anything you want.
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 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, 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. 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.
I don't read AC A human right
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.
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.
The plant is, in fact, a reverse osmosis plant.