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Water Now More Awesome Than Previously Thought
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."
Do you have any idea how much water there is in the ocean? And what the specific heat of water is? By the time we're pulling enough energy to make a difference, we'll have colonies in multiple solar systems.
The "limitless energy" claim is pure hype, but just ignore that bit.
As you point out, it is also important to evaluate the long term affects of removing significant amounts of cold water from the oceans (disrupting ocean currents, overall water temp. rises, etc). The drinking water generator would also lower the air humidity, which would cause problems if the project was done on a wide scale.
I am sure this technology has applications in some circumstances (perhaps on oil rigs, remote islands, etc), but it is certainly not the solution to all our energy problems. Done on a large scale it would be unsustainable.
I'm still waiting for practical fusion power...
Luckily it's pure grade-A horse poop.
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.
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...
This is a fantastic idea, except for one flaw. This would only work for cities near the coast.
That's a goodly majority of all humanity.
C//
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.
Find free books.
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.
Raise your children as if you were teaching them to raise your grandchildren, because you are.
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.
When the people fear their government, there is tyranny; when the government fears the people, there is liberty.
chilling the moisture out of the ground is going to dehydrate that soil, causing things to die.
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
The only title of honor that a tyrant can grant is "Enemy of the State."
Damn you and your improper nomenclature!
You don't enumerate singular atoms in inorganic molecules. The proper term is dihydrogen oxide.
No, discharging sewage into the ocean can have unintended effects. That's the real problem.
Insulate the pipe?
Cold water is MORE DENSE than warm water. In fact the point of maximum density is about 4 degrees C, below that it gets less dense again (unlike most substances). But I didn't see the article mention the actual temperature of the water that's being extracted here, so maybe it is sub-4.
My concern is, what if the pipe sucks up all these exotic bottom-dwelling fish?
Canada literally taxes people to death, levying high taxes
if you add what americans pay PRIVATELY for their health care to their tax bill - wait for it -- they become the most taxed people on earth.
canadians arent taxed much really, consider what we recieve in return.
amoung other things, universal healthcare of dubious quality and value
nonsense. The care is excellent. I refer you to the 100% coverage, illness rates, infant mortality rates and life expectancy. Anactodal testimony that the system 'has too many waits' is mcdonalds-mall-shopping mindset where it isnt necessary. guess what: sometimes you have to wait. in the end, the only result is you couldnt cope with not being able to demand instant attention... which is really what the immature/uneducated are using as motivation to insult CHC.
For what my father paid in that share of his taxes earmarked for national health care, his life could have been saved ten times over. Instead, an operable, discovered abdominal aortic aneurism was left untreated until it ruptured, killing him.
Im sorry for your loss. But unfortunatley, some people die. Blaming your father on CHC is dubious. One person's loss isnt reason to consider the system broken. We are dealing with a massive system. Its got to be flexible but efficient.
In the end, its still provides excellent care. There is no disputing this.
But, why is it that Canada punishes traditional marriage and home ownership with its tax code?
For welfare bums, perhaps. But certainly not for hardworking breadwinners: mothers and fathers struggling to put a roof over their kids' heads.
Get off the fraser institute/reform mailing list. Youve fallen off the deep end. Those "welfare bums" you speak of are the middle class pal. Fostering the middle class -- or the general welfare -- is should be the sole goal of government.
Is your alternative the american-style gap between rich and poor and its accompanying chaos? no thanks.
Almost all of industrialized world has a social welfare system similar to Canada. Japan, australia, europe etc etc etc. *THIS* is why we have high standards of living -- by definition.
America has a high standard of living because of its massive income... being at the top of the financial shitpile has its advantages (like being able to spend yourself onto the point of respecable OL-index), but their system is *NOT* a model to emulate.
It *WILL* not work for anyone but the super rich. And, really, unless your superwealthy (ie: not middle class) than your self-interest is not served by wanting the changes you think you do.
Its american jingo rhetoric infecting your politics pal. its time for some perspective. Take a trip to europe. read some foriegn papers.