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New Power Plant Produces Both Energy & Fresh Water
joshmccormack writes "An article in Sunday's New York Times (Free Reg, mah peeps) tells of how Japanese scientists have found a way to make fresh water and energy from temperature differences in ocean water. This may change the rules of what land is considered habitable, and the value of energy." Fascinating stuff, next step is rumored to be beer and power.
FP? Anyway, I've visited that type of plant (OTEC, Ocean Thermal Energy Conversion) already in Hawaii (near Kona), where there is one running since quite some years. One problem is that it only works for steep ocean wall drop offs, since otherwise the pipe is getting too long.
It uses about half of the created energy (through a normal Carnot cycle) for pumping (about 120kW). The other half is not quite competetive, but with the nutrient rich and cool water, fish farming and air conditioning can be done, heaving the whole investment to a black zero (or better).
I leave the exercise of finding the link to a Karma-hungry reader.
Hurricane Application Group, Dept of Meteorology Control, Ministry of Proactive Defense
Temperature difference in sea.
the temperature difference is enough to liquify certain gasses, and then expand it again.
Just like the refrigerating unit.
Not to mention the increase of pressure water gets deeper.
Having lived on a island in the south pacific for a year I learned how important fresh water is. The aircraft landing strip that we had acted as a big water collector - water would drain into pipes and then was cleaned by a chlorination process. The idea they propose is a good one and would work in many islands out there - where they desperately need easy access to electricity and fresh water.
I heard that in America Beer is less tasty than water.
Bringing cold water from the depths has an unmentioned potential side-effect. Will it be replaced by warmer water from elsewhere? Cold, deep waters often support amazingly rich ecosystems. Raising the temperature even a few degrees could easily destroy entrie habitats. Will these generators warm the depths, and what effect will that have on the deep ecosystems?
Fresh water and clean energy? Sounds awfully unamerican and likely to support terrorism.
When I was about ten I read one of those cool-science-futures-for-kids magazines, which showed a floating OTEC with a vertical downpipe - that makes more sense, as it doesn't rely on rare coastal relief. I believe Bruce Sterling's novel Islands in the Net also had similar floating OTECs. Perhaps building such a device of the necessary scale (you have to pump a lot of water around, after all) just isn't economic?
Even if you do get mass OTEC production working, its quite debateable if it's really such a good idea. It's a lot of effort (money, materials, time) devoted to something that doesn't generate a terribly impressive amount of energy, and by its very nature it both warms the deep water and cools the surface water, which will have localised environmental consequences.
I despair that everyone is concentrating on renewable resources while so many people (particularly in hot western US states) live in essentially uninsulated houses with single glazed windows. Biomas, geothermal, wind, solar, and ocean generation are all expensive and uncertain - tripleglazed solarglass windows and super-thick wall insulation are available fairly cheaply right now, are guaranteed to pay for themselves way before a windmill, an OTEC, or even a biomass plant. Yet still we're paying to air condition the sky.
## W.Finlay McWalter ## http://www.mcwalter.org ##
It still is. As it turns out in reality, the 20th century was the one with the least chaotic "earth weather" and we now try to use _that_ as a baseline for "how it should be".
It won't work. The earth has a weathersystem totally independent of what us tiny humans do. Read up on the "small ice age" just a few hundred years ago, or where the "dark middle ages" got the nickname from.
"Global warming" is a myth. A popular one, but a myth nonetheless. "Global cooling" - which was popular a few centuries ago - is actually more likely to happen.
it's in my head
Yes, but I think we all remember what happened last time the Japanes messed around with power plants. That's right: Godzilla. With Mothra defeated and major military forces otherwise occupied, the situation looks grim! Beware the denizens of the deep!