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California Looks To the Sea For a Drink of Water
HughPickens.com writes Justin Gillis writes in the NYT that as drought strikes California, residents can't help noticing the substantial reservoir of untapped water lapping at their shores — 187 quintillion gallons of it, more or less, shimmering invitingly in the sun. Once dismissed as too expensive and harmful to the environment desalination is getting a second look. A $1 billion desalination plant to supply booming San Diego County is under construction and due to open as early as November, providing a major test of whether California cities will be able to resort to the ocean to solve their water woes. "It was not an easy decision to build this plant," says Mark Weston, chairman of the agency that supplies water to towns in San Diego County. "But it is turning out to be a spectacular choice. What we thought was on the expensive side 10 years ago is now affordable."
Carlsbad's product will sell for around $2,000 per acre-foot (the amount used by two five-person U.S. households per year), which is 80 percent more than the county pays for treated water from outside the area. Water bills already average about $75 a month and the new plant will drive them up by $5 or so to secure a new supply equal to about 7 or 8 percent of the county's water consumption. Critics say the plant will use a huge amount of electricity, increasing the carbon dioxide emissions that cause global warming, which further strains water supplies. And local environmental groups, which fought the plant, fear a substantial impact on sea life. "There is just a lot more that can be done on both the conservation side and the water-recycling side before you get to [desalination]," says Rick Wilson, coastal management coordinator with the environmental group Surfrider Foundation. "We feel, in a lot of cases, that we haven't really explored all of those options."
Carlsbad's product will sell for around $2,000 per acre-foot (the amount used by two five-person U.S. households per year), which is 80 percent more than the county pays for treated water from outside the area. Water bills already average about $75 a month and the new plant will drive them up by $5 or so to secure a new supply equal to about 7 or 8 percent of the county's water consumption. Critics say the plant will use a huge amount of electricity, increasing the carbon dioxide emissions that cause global warming, which further strains water supplies. And local environmental groups, which fought the plant, fear a substantial impact on sea life. "There is just a lot more that can be done on both the conservation side and the water-recycling side before you get to [desalination]," says Rick Wilson, coastal management coordinator with the environmental group Surfrider Foundation. "We feel, in a lot of cases, that we haven't really explored all of those options."
Wouldn't help much. They bottle about 500 million gallons of water a year. California residents use about 1 trillion gallons a year (about 10% of California's yearly water usage). To put that into perspective: almond farms use about 1.2 trillion gallons a year; alfalfa farms use about 1.5 trillion gallons a year.
Let's be honest here. The rate and methods by which we are consuming resources from environment is akin to a clueless child playing around the stove. Sometimes we need to get burned by the stove to learn not to touch it again. And the drought in California is natures way of telling us our hand is currently roasting on said stove.
Start whacking industries who use the most water with a levy to pay for the plants. e.g. almond growers. If they are suddenly motivated to develop ways to save water then fine, if then don't then it's still a new plant.
in america we are expected to shower daily
At first I thought that the 'Acre-Foot' sounded like a joke unit, but obviously it is the amount of water that one hundred and twelve horses need to drink if they are each to plough eight hundred furlongs of furrow in a fortnight!! Honestly, you Americans just crack me up with your wacky units. So much more fun than being stuck with boring old litres!
Just 20% of water usage in California comes from residents and non-ag businesses. 80% of water usage comes from agriculture. Almonds alone (70% of which are exported out of the country) account for about the same amount of water as all residences in the state.
People could switch to a two-minute shower once a week and it wouldn't make a measurable difference. Flood irrigation in a desert is the real problem, and until that's universally recognized, nothing will be solved.
If you retrofitted all almond groves to use drip irrigation, you could maintain the same crop output at less than half the water usage. Why not? Because it costs money, and growers would rather just pull more from their wells. The aquifers in California are a true Tragedy of the Commons.
Agriculture is the big culprit, taking 80% of the state's water (and in return ag and mining together only make up 2% of the economy). Its a totally unsustainable situation that has to be remedied sooner or later.
That said, I do have hope for the future of desalination. Not with current techs (as with the one in the article, they're energy hungry and expensive), but potentially with new techs that don't rely on electricity as their power source. One I find interesting is this one. Basically, it relies on evaporation, which isn't unique... but *not* by capturing the evaporated water. It's just concentrated salt solution that's desired, which means that you don't need some sort of elaborate vapor capture system and sealed tanks, just simply any sort of open area that can hold water - even an endoherric basin or jettied-off chunk of ocean. Far, far cheaper.
Concentrated brine is turned into freshwater via ion bridges: it's connected to two tanks of normal seawater, one by a positive ion bridge and the other by a negative ion bridge. The brine greatly wants to dilute into the normal seawater, but it can't because the ions would be imbalanced in the two side tanks. So these two side tanks are connected to a third tank of seawater with the opposite ion bridges, so that salt can dilute from the brine into the two seawater tanks, but only if they also "suck" the opposite ion out of the final seawater tank. Since the brine concentrated brine wants to dilute so much, the action is energetically favorable and continues until there's no salt left in the third tank - aka, it's freshwater. (An actual implementation would be a continuous process, not fixed tanks, of course)
Apart from basic pumping needs, there's no electricity needed. The energy source is just "sun falling on any water chunk of seawater that's not free to circulate with the open ocean". You might even be able to have it filled automatically in some places via the tides or waves breaking over a jetty without having to pump new seawater in, leaving the only pumping needs for distribution.
Of course, the main tech limitation right now is making the salt bridges have high enough throughput and reliability to justify the capital costs.
Trump's plan to get rid of Mueller appears to be 'be so guilty of so many things that Mueller works himself to death.'
I want that, mine was $141 last month. We had an increase this year by $5 a month because the lake is dry and they had to drill a bunch of water wells. A local private water coop regularly charges $200 a month. Suck it up Calif. If we can afford it in west Texas, you can in calif.
They should not be using electricity in the first place. Desalination is a perfect pairing for cogeneration with Gen IV fission plants. Added benefit is you can put the entire output to desalination when demand is low to avoid using peeking plants.
No sir I dont like it.
Solar isn't nearly efficient enough to do that without pretty much paving over the entire southwest with solar facilities
Bullshit. The Ivanpah Solar Power facility is only 1% of the Mojave desert area, and can produce enough energy for several of those desalination plants.
Desalination is an ideal use for fluctuating power sources in general. Instead of spending trillions to put wind and sun on the grid, use them to provide water for California and Texas. At the same time, we won't be using energy-intensive R-O forever. Cheaper desalination tech improves the equation.
Almonds alone (70% of which are exported out of the country) account for about the same amount of water as all residences in the state.
That's why in other countries they have made farmers switch to more suitable crops that don't need so much water, or do as you suggest and use more efficient watering methods. Almonds are nice and all but is it really a good idea to use so much of your limited water supply on them?
That's why I mean by lifestyle. Not just showing less (FYI we shower just as much in Europe), changing what you eat, what you grow, what industries you allow to use massive amount of water. Ask yourself why almonds continue to be grown, even though it is causing so many problems.
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SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
Unless you pump the excise brine directly back into the ocean and kill all the life around the pump outlet. Similar thing happens with CO2. I've head the specious argument we don't have to worry because we're just recycling CO2 by burning coal, oil, and gas. Yes, that's true. However, it is important to note that all the sequestered CO2 put into the atmosphere isn't mere recycling.
As in everything, it is important to have a sense of proportion. Math is your friend.
Yeah, but that would require an immense surface area to work. You'd have to cover approx 70% of the planet with water. No one would go for it and the environmentalists would have a fit.
I tried every decent and legal way I could think of to resolve the issue w/the business before I rented the chicken suit
I think that the 70% export figure indicates that while "other countries" have switched which crops they grow, they haven't changed their almond consumption rate. Similar to how the western world has eliminated the environmentally destructive extraction techniques necessary for rare earth metals, but still buys cell phones because China is willing to take the hit.
"Because Science" is one step from "Because old book". Try "Because of my experiment testing my falsifiable assertion".
And the whole idea that desalination destroys the environment somehow is an example of why I have zero respect for environmentalists
The environmental problem with desalination is not that it "uses up" water, but that it is a voracious consumer of energy. It is idiotic for San Diego to produce expensive and energy intensive desalinated water, when a short distance away in the Imperial Valley, farmers are receiving water for a hundredth the cost. Central planning has been a failure everywhere, and it is failing in California. The government should not be picking winners and losers, or segmenting the market into favored certain sectors. Instead they should just let the market set the price for water. The alfalfa and rice farms will disappear from the desert, and the desalination plants will not be necessary. We don't have a shortage of water, we have a surplus of stupidity.
San Diego has the cleanest power of anywhere in the whole US. They currently get over 25% of their power from renewable sources such as wind and solar and 67% from natural gas. They burn ZERO coal or oil. They are the model for the whole US.
Peter predicted that you would "deliberately forget" creation 2000 years ago...
Desalination on the level being talked about here would produce huge amounts of salt and other minerals. Getting rid of that salt in a way that wouldn't cause catastrophic harm would be no mean feat.
Are you serious? You are aware that sea salt is a thing, right? Even if it's not suitable for human consumption, you can still use it to grit the walk.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
What exactly is your criticism of my post? Your's is so bizarre and confused it's difficult to tell.
I was perfectly able to understand his post. He pointed out that there are commercial uses for salt. On the other hand your post and attitude seems to scream of a lack of thought. I have no idea how anyone can write this line
Desalination on the level being talked about here would produce huge amounts of salt and other minerals
As if it is some sort of problem.
I can see another aspect besides the waste in electricity... The microscopic life in the ocean that is the foundation of the food chain that will eventually lead to us is not considered in the environmental assessments. They are only worried about the higher multi-cellular life. The ocean is one of the most diverse places on Earth. I can see us fucking up that diversity much like we fucked up everything else we touched in nature.
This is a sig. This is only a sig. Had this been an actual sig you would have been informed where to tune for more sigs.
"A hundred billion gallons of water per year is being exported in the form of alfalfa from California," Robert Glennon, a professor at the James E. Rogers College of Law at the University of Arizona, told the BBC, which claims it's now cheaper to send alfalfa from Los Angeles to Beijing via ship than to truck it from the Imperial Valley to the Central Valley."
http://www.bbc.com/news/magazi...
I don't read your sig. Why are you reading mine?
The high cost of desalination is for the current reverse osmosis process, which requires high pressure to force the water through separation membranes. Now that graphene manufacturing is starting up (watch for the brand name Perforene), the cost of desal will fall off a cliff.
The high pressure is not because of the membrane resistance, but because of the osmotic pressure. That is not going away, unless some fundamental physical laws are repealed, including the first and second laws of thermodynamics. Better membranes can make a small difference, but not much. Also, for some weird reason, oceans tend to be located in low lying areas, so you need to factor in the cost of pumping the water uphill to the users. Pumping water already uses 10% of all the electricity generated in California.
Maybe the entire country could stop massive subsidies for farmers to grow crops in what amounts to coastal steppe/desert? Oh, and the massive subsidies allowing millions and millions of people to live in deserts (and yes, I'm not just looking at California).
It was a stupid policy in the early 20th century, but at least then there was the incentive to populate the (south) west coast for geopolitical/security reasons. Now, simply start charging people (farmers, corporations, individuals) the ACTUAL costs of the water they use and let the market cull the system. /solved.
-Styopa
Citations? Here're mine:
USA uses about 1500 m3/capita/year, which is similar to New Zealand (1200 m3/capita/year) and Canada (1400 m3/capita/year). Compare with California alone, we're at 178 gallons/capita/day which is 245 m3/capita/year. That's lower than most countries.
Look, dude...
Your 1st link is total consumption. Agricultural + municipal + industrial.
In your 2nd link, the "178 gallons/day" figure is for municipal use only.
Pro-tip: when you get such massive discrepancies (1 to 6 !) between two similar populations, especially when one includes the other, it's worth checking it up a bit more carefully.
I generally support Nuclear power, but in reference to old plants shutting down? Good. Old reactor designs need to be retired, because quite frankly they're not safe enough compared to what's available now.
No, the problem isn't that older plants which have seen significant wear and tear face too many regulatory hurdles to continue operating - it's that NEW plants, using more advanced, safer technology, are facing too many legal hurdles in most cases to get built. We're talking about Passively Safe fourth-gen reactors, the sort that would be able to survive even something like Fukushima without a meltdown. We can't get these old plants replaced with new ones, so the old ones keep running with increasingly creaky equipment? That strikes me as downright crazy.
You're not counting groundwater. Nut crops are so profitable that farmers can afford to drill million dollar wells to make up for their lack of surface water allocations and still make money.
California's groundwater is completely unregulated and at this moment, and our aquifers, which take thousands of years to build up, are being irreparably damaged.
I don't always use unix-like operating systems; but when I do, I prefer FreeBSD.