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.)