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Water Now More Awesome Than Previously Thought
Posted by
samzenpus
on Wed May 25, 2005 07:33 PM
from the it's-like-you-can't-live-without-it dept.
from the it's-like-you-can't-live-without-it dept.
Dan writes "Wired has a great article about a guy who thinks we can provide unlimited energy , accelerate crop growth, desalinize and purify drinking water, obtain health benefits and provide air conditioning, all by pumping up water from the depths of the ocean."
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More Efficient Coastal Farming (Score:5, Interesting)
I like how he irrigates the farms. The sweating of the pipes below ground is a great idea. It seems much more efficient than spraying water everywhere, and having a lot of it evaporate.
He may be a nut (or not, I'm not a good judge of character), but he does have a great way of looking at his environment.
Re:More Efficient Coastal Farming (Score:5, Informative)
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Re:More Efficient Coastal Farming (Score:5, Interesting)
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Re:More Efficient Coastal Farming (Score:5, Funny)
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Re:More Efficient Coastal Farming (Score:5, Informative)
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Re:More Efficient Coastal Farming (Score:5, Insightful)
Maybe I've forgotten too much of my highschool physics, but how does this really work? I was under the impression that the "sweat" on cold pipes is the result of the chilling of the surrounding air/material, which lowers its capacity for carrying water, thus in essence extracting it into solid form.
So if the pipes sweat below ground, aren't they simply solidifying water that already is in the ground? If so, that's not what I'd call irrigation...
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Re:More Efficient Coastal Farming (Score:4, Interesting)
And to top it all off, chilling the moisture out of the ground is going to dehydrate that soil, causing things to die. There's a good reason that cooling systems are used for dehumidification.
However, if they're talking drip irrigation from buried pipes, then it's an excellent idea. However, it's nothing new. You can buy the materials to set a system like this up in your garden from the nearest hardware store with a decent lawn and garden department.
And any water exposed to open air is going to have a certain amount of evaporation, so i'm not sure why he's on about that. I'd be willing to bet it's more efficient from an evaporation viewpoint to spray the water from above, since evaporation causes cooling. Cooling causes dehumidification of the surrounding material by condensation. If you evaporatively cool the soil by drip irrigation, the soil cools and releases it's moisture faster. It goes into the water table or an underground aquifer, taking with it unused nutrients, unsettled herbicides, unspent pesticides, and it still doesn't reach the plants for the time needed for them to absorb it. If you instead evap-cool the air above it, the water condenses out of the air and falls onto that soil, hydrating it and leaving nutrients and chemicals undisturbed for a longer time.
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Re:More Efficient Coastal Farming (Score:5, Insightful)
Only if you're pumping that water off somewhere else. If you just use the pipes to chill the ground, then water from the air condenses on the ground. Upshot: irrigation.
-jcr
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Re:More Efficient Coastal Farming (Score:5, Interesting)
The problem is, in costal areas, fresh water for irrigation is scarce, and current desalinization processes are expensive. His cold water system is an inexpensive (almost free) method for generating fresh water, and as such is practical for providing for irrigation as well as potable water.
FYI, pipes sweat because the water (or whatever) fluid flowing through them is colder than the surrounding air, which causes water vapor in the air to condense on the pipes. This is the same principle used in dehumidifiers, though the water is usually an unwanted by-product in that case.
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Re:More Efficient Coastal Farming (Score:5, Insightful)
That's a goodly majority of all humanity.
C//
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Re:More Efficient Coastal Farming (Score:5, Funny)
Yeah, then there'll be no such thing as coastlines anymore.
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Re:More Efficient Coastal Farming (Score:5, Funny)
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Re:More Efficient Coastal Farming (Score:5, Informative)
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Re:More Efficient Coastal Farming (Score:4, Insightful)
As is the case in this pilot project, the hardest up locations for resources are often islands so initially this may be a viable solution.
Then consider how fast the Pacific drops off near Monteray CA. Consider Japan, Korea, Indonesia, east coast of India...turn on the satelite view in google maps and see how many populated coasts are near continental shelf drop-offs.
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Ha, whatever (Score:4, Funny)
You're just numbing the pain. Idiot.
Amateur. (Score:5, Funny)
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Re:Do continue! (Score:5, Funny)
That little headache problem was due to my prematurely stopping the drinking cycle too early, causing pain. Well, friend, I won't make that mistake again. I pledge to you that I will drink, nonstop, from here on.
Slashdot, I salute you!
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Never dealt with sports injuries, have you? (Score:5, Interesting)
Funny thing is, heat kinda does the same thing, albeit not as effectively. Most folks don't like the ice and go for the heat for injuries, though, because heat "feels better". Icing an injury can actually be painful - drop a sprained ankle into a large bucket of ice and water for ten or twenty minutes and the first minute or so will have you twisting and turning and writhing as your foot hurts like hell from the cold water. The pain does go away though after a minute or two.
Heat won't cause that pain. But heat will increase the internal bleeding from an injury if it's not fully healed yet, making the injury worse. Icing an injury will help stop any internal bleeding.
At least that's what my college football trainer told me one time as I was sitting waist-deep in a whirlpool of ice and water to treat a pulled groin muscle. Talk about having your balls shrivel up...
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Re:Never dealt with sports injuries, have you? (Score:5, Informative)
The poster's exactly right. Applying both ice and heat to an injury manage the circulation to the area.
When you have an acute injury, say, a sprained ankle, you get an inflammatory response -- swelling. That's nature's way of splinting and immobilizing the injury. That problem is that all that swelling later turns to scar tissue, in essence, crippling you afterwards.
What you're trying to do is to use cold to decrease circulation during the acute phase of an injury (to reduce swelling), and to use heat and motion to increase circulation during the chronic phase (to help break up scarring and create new muscle and bone). The rule of thumb is ice for the first three days, then heat, but really, you want to ice as long as there's heat coming off the injury.
Both ice and heat will make you feel better. In my experience, ice is initially less comfortable, but WAY more effective in the end. And, ice combined with Aleve is even better.
As an aside, ultrasound therapy works the same way as heat, albeit in a more focused and comfortable way. You never want to use it acutely, but for things like old hamstring injuries, it's the freaking bomb.
During rehab, (and frankly, if you're playing competitively, you're ALWAYS in rehab) you end up using both heat and cold. Usually, that's heat beforehand (to increase flexibility and circulation) and cold afterwards (to reduce inflamation from the trauma to old injuries). After a while, you just get used to the routine -- although spending a half hour with your balls in an ice whirlpool is never any fun.
No, I'm not a doctor or a physical therapist, but after a broken leg, a blown hamstring, one remaining ligament between two ankles, twenty five years in the cage, and a trip playing in the World Games, you get to know these things...
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Convenient... (Score:5, Funny)
Stupid planted articles...I'll buy what I want!...oooh...clock...
Obligatory Comic Book Guy... (Score:4, Funny)
I see a flaw. (Score:4, Interesting)
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Re:I see a flaw. (Score:5, Informative)
The articale mentions that once the system is primed, it takes very little energy to keep pumping.
Think about it. You're not pumping water up into the air, you're pumping water above other water. Without any pumping, the water will automatically lift the water to, you guessed it, sea level. You only neet to lift it the extra 30 feet to your beach side farm.
Getting the system started probably takes a lot of power as you have to get all the water in your pipe moving fast enough so the water won't warm up by exchanging heat with the outside water, but one it's moving, inertia will help you keep going. You only need to make up for friction, and for the fact that cold water is slightly less dense.
Then again the article mentions that the pipe acts like a siphon, so maybe there is some other effect I can't think of. Maybe the decreased pressure because of the pump makes water freeze and therefore rise? dunno.
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Re:I see a flaw. (Score:5, Informative)
If true, that is a truly neat hack.
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Dihydrogen Monoxide (Score:5, Funny)
ocean temperatures? (Score:5, Interesting)
Maybe it will turn out like windmills- they take negligible energy out of the wind.
Re:ocean temperatures? (Score:5, Informative)
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Re:ocean temperatures? (Score:5, Interesting)
Perhaps. Perhaps not. In Huntington Beach, California, for the past several years, the beaches have had to be closed during the summer due to bacterial pollution. The obvious cause was the wastewater treatment plant dumping partially treated sewage 7 miles off shore, and that was somehow coming back onshore. Models, however, demonstrated that this was very unlikely because of water column stratification based on temperature (colder water, more dense, can't come up).
One factor not included in the models was an electrical generator station on the beach that drew in ocean water for cooling. It would discharge the warm water back to the ocean. However, it discharged the warm water at depth. Warm water, being less dense, rose to the surface, creating a nice thermal pump that would carry with it the colder water at that depth, some of which was certainly co-mingled with the discharged sewage. (this wasn't the entire reason for the beach pollution, but certainly was a contributing cause.)
So, yes, discharging warm water back into the ocean can have unintended effects.
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Re:ocean temperatures? (Score:4, Interesting)
Turns out the problem is when it rains, the sewage treatment plants reach compacity and dump untreated sewage into the ocean(this is pretty prevalent in the long island sound and would happen anywhere there is sewage treatment facilities and rain).
Overflow spillage happens much closer to shore usually than any pipe they send out and 7 miles seems way excessive as the outflows i visited were at best 3 miles from the plant, most much much closer, like 4 - 8 hundred yards.
The algae bloom and nitrate concentration near these pipes was insane. In fact in the long term this increases algae so much surface algae becomes so thick once vibrant life deeper down gets no light, dies, creates more bacteria and it can become a run away reaction. Eventually the algae bloom can cause massive amounts of fish to die, then mammals and so on.. quite nasty.
But the problem happens without any warm water being added back into the ocean. Likely its just not understanding that its compeltely raw sewage overflowing because the plant cannot handle rain load and sewage load at the same time.
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Re:ocean temperatures? (Score:4, Funny)
(ref. [brainyquote.com])
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dude (Score:5, Funny)
very low thermal efficiency (Score:5, Informative)
Yes, you can get energy, but not much.
Re:very low thermal efficiency (Score:4, Interesting)
What scares me is the environmental impact. These plants will pump a lot of bottom water back out near the surface. Because of the low efficiency, it will be a huge amount of water compared to the capacity of the power plant. Water near the bottom is oxygen poor because nothing can photosynthesize in the abyssal dark. It's nutrient rich because there's a steady rain of dead things from above. Dump that into hot oxygenated surface water and you're making an ecological change, which means the results are unpredictable. If you're lucky you get better fisheries from a fertilizing effect.
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Re:very low thermal efficiency (Score:5, Insightful)
A 2% efficiency isn't a problem. Efficiency tells you the ratio of the energy you can sell to the energy you put in. But if the energy you put in costs zero, then efficiency is an utterly unimportant number.
What's more relevant is to compare the cost of building the plant to the money you can make by running the plant over its planned lifetime. That's the relevant figure of merit for a nuclear power plant, and I think it's the relevant one for an OTEC plant as well.
The problem is that fossil fuels are artificially subsidized. Say I increase my energy use, and use an extra megajoule of energy derived from burning coal or gasoline. Well, I don't pay anything extra for the damage I'm doing with global warming, and I also don't pay enything extra for all the wars in the Middle East that the U.S. keeps getting into.
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But it's not just a power plant (Score:5, Insightful)
There are several factors that make up for the inefficiency in power generation:
Places like Saudi Arabia and Chile, which have lots of sun and salt water, but almost no fresh water, should jump on this. Saudi Arabia in particular, which has all the power it needs, could really benefit.
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Age and whatnot (Score:4, Funny)
This guy is even cooler than you might think (Score:4, Interesting)
Some of his ideas are nuts (Score:5, Interesting)
In theory cold-water energy works; anytime you have a temperature differential it can be harnessed to create energy according to the laws of thermodynamics. In practice, I'd question whether the constant pumping and maintenance (saltwater is highly corrosive) wouldn't require more energy than you get out of this system.
One more thing: it's all fun and games until you suck a whale into the input pipe! But seriously, if you pump up nutrient-rich soup from the deep, in a few years your pipe is going to be so clogged up with marine critters that your flow rate is going to tend towards zero...
Re:Some of his ideas are nuts (Score:5, Interesting)
Not to mention it'll be damn traumatic for anyone who digs out some of the deep sea's scarier denizens [oceans.gov.au] from those pipes...
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He Doesn't Have the Half Of It... (Score:5, Interesting)
It is a key component in life; it's solvency and structure are what makes biochemistry work.
It has about the widest range of temperature as a liquid of any simple material - making life possible over the face of the earth.
It is the closest thing to a universal sovent we will ever see.
Since it expands on freezing ice floats - just think what a mess the oceans would be if they were made of something that shrank when it froze, and the ice sank. The planet would have much wider extremes in temperature just because of that small fact.
Wate has an immense heat capacity compared to other liquids... moderating our weather
The beat goes on; it's unique chemistry and physics are whe we live off of every day.
Cold Shower (Score:5, Funny)
Faster growing fruit + unlimited energy + free air-conditioning = multiple orgasms (profit!!!)
Aspects of this already in use (Score:5, Interesting)
Re:Like all energy sources.... (Score:5, Insightful)
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Who modded him insightful? Try -1, utter nonsense (Score:5, Interesting)
Ok, take a deep breath, and try to develop a sense of proportion. Oceans are big. Very, very big. We're talking miles deep, and thousands of miles across.
Ocean thermal plants will work with pipes that are very, very small in proportion. Even 100-meter diameter pipes raising cold water from the deep, will have an effect that's just about immeasurable.
Ocean thermal energy poses no more hazard of disrupting ocean currents, than windmills do of stopping the wind.
-jcr
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Re:Like all energy sources.... (Score:5, Informative)
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Re:Good, but... (Score:5, Informative)
Because there are only a few islands throughout the world where it's practical. If you have a continental shelf, it ain't gonna work.
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Re:Good, but... (Score:4, Interesting)
The biggest problem that I see is one of location. For a lot of this stuff to work, you need a few different things:
1. Cold, deep water.
2. Warm surface water.
3. Warm, humid air.
So you're limited to equatorial regions with available deep water. The UK won't be using this.
m-
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Re:This is fantastic! (Score:5, Insightful)
Er, no, not really. Granted, this particular guy sounds a few gallons short of a hogshead, but deriving useable energy from cooling things off works exactly the same way as by heating them up - Namely, we can use the transfer of energy from the warmer side to the colder side to perform useful work (such as generating electricity). The absolute temperatures involves don't particularly matter.
So why do virtually all human-created energy extraction technologies use warmer than ambient going to ambient as the two sides? Simple... We humans have enjoyed, at least for the past few millenia, a really easy way to get things hot (ie, fire and a supply of fuel that literally grows on (as?) trees). We have not had a convenient way of making something colder-than-ambient, except very recently (within the past century), and even then only by using the hot-to-ambient conversion to get electricity to do the ambient-to-cold conversion - Sort of trading one for the other, with a net loss in both conversions.
Deep ocean water, however, provides exactly that - A nearly limitless supply of something colder than ambient, with a high enough specific heat that the energy we can extract from the temperature gradient FAR exceeds the energy needed to pump it in the first place.
Imagine the climactic effects, and effects on the oceans ecosystems
Now, here you make a good point. In the short term, or on a small scale, I would tend to say that we couldn't even come close to the natural processes that mix the oceans. But then, people thought the same about burning wood and later oil, until just the past few decades.
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Re:Deep Sea Environment? (Score:4, Informative)
As far as benthic thermal pollution, it already exists in the form of deep ocean thermal vents. Of course these are natural, even though they spew vast amounts of sulphur etc. I would suspect the ecosystem down there would handle this pretty well, since by the time the warm water got back down it would be nearly the same temperature as the surrounding water.
Of course, it would be wise to run a full-scale test for a few years to determine the localized impact on the biosphere,(before widely deploying it) but I wouldn't jump to any conclusions until we see the findings.
m-
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Re:P.H.D. (Score:5, Informative)
Ocean Engineering is a field of civil engineering, which is concerned with construction on coasts or under water. Offshore oil rigs are designed by Ocean Engineers, for example.
-jcr
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