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Solar ponds  RSS feed

 
Posts: 17
Location: Ohio
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A friend of mine told me about solar ponds, artificially created ponds of salt water which collect and store solar thermal energy and are "used for various applications, such as process heating, desalination, refrigeration, drying and solar power generation."
(The wiki page is here.)

Basically, from my limited understanding, the salt water pond collects and stores thermal solar energy and creates a salinity gradient (called a halocline) where low salinity water floats on top of high salinity water. There are 3 layers, the top most is low salinity water and is the coolest layer, the middle is an insulating layer that prevents heat rising through convection, and the lowest is high salinity and stays warm. Normally the heat would rise to the top by convection but the temperature gradient (in which density decreases with depth) is counteracted by the salinity gradient (in which density increases with depth) thus preventing convection. Because of this the lowest layer can exceed temps of 90 degrees Celsius while the top tends to stay around 30 degrees. (Sorry for the piss-poor description. I recommend the wiki page for more in-depth, understandable information)

Has anyone heard of this before or utilized it? Anywhere I can get more information? I was mostly interested in it for the sake of heating but apparently it can be used for energy too.

(Also, I apologize if this is not in the right forum, I honestly wasn't sure where to put it.)
 
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Hello Saer,

Israel was first to publish on solar ponds. There currently are some in commercial use in Australia. Very simple to make. To create such one must actualy layer the water, that is first a high brine pool, then gently adding to top of that a lesser brine pool, followed again by a lesser brine pool. Salt cannot be added to the pond the brine must be made outside the pond then gently added. The heat pick up pipes run along the bottom of the solar pond in closed loop cycle. The thermal energy gathered is excellant if high reactive gas is used in driving a turbine, or the heat transfer may be used to any other purpose.

Cheers Peter
 
Saer Greason
Posts: 17
Location: Ohio
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Well that's neat. I was wondering how they managed to get it to settle into layers and produce heat when a normal salt water pond (like a desalination pond) does no such thing. Thanks for the awesome info Peter
 
Peter Mckinlay
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Hello Saer,
My appologies if I am repeating a post, that prior submitted is not appearing.
Should you wish to generate electricity from a solar pond the DaS Turbine/generator may be of help.
A slight alteration is needed as the design is for collection of ambient heat to heat CO2 sealed in the pump and turbine. However the pressure developed to run the turbine may be generated in the pond pipe work and fed to the pump. This device we have released in Open technology free to all.
The complete device may be home made or constructed using of the shelf parts.
Electricity production begins at a pond temperature of minus 10* and the highest temperature we are able to provide is plus 100* Celsius.
The attachment is a one litre turbine/generator spinning at 60 RPM which at minus 10* Celsius produces 720 watts rising to 72,000 watts at plus 100* Celsius.
Wattage output increases by three ways, increasing the volume of the turbine, increasing the rotational speed of the turbine, increasing the temperature of the CO2 being fed to the turbine pump. happy to help where I can.
Cheers Peter
DAS-FINAL.JPG
[Thumbnail for DAS-FINAL.JPG]
Gas powered Hydro turbine/ generator.
 
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