Have you ever wondered, that people living in cities are so paradoxical? It’s hard to please us, because we, are so confusing. We want to feel cool, but when bathing, the water hot. One moment we consume iced drinks, the next minute, snuggle in our blankets, with the air-conditioning blasting while we sleep.
(creative commons)
This generates a lot of energy wastage, from my idealistic point of view, heat energy isn’t going to where it’s needed most i.e. inefficient distribution. Recently I read up about this idea of the Solar Pond. It is not state-of-the-art technology, in fact it has been around for a few decades already. Funny that it took me this long. Nevertheless…
Like many others, it is an ingenious idea, based on simple concepts. A normal column of water naturally has its convection currents ongoing, and after a substantial amount of time untouched, it would be in thermal equilibrium.
(2)
Basically, in this tub, the base designed to be super heat-absorbing, possibly coloured black, and copious amounts of salt is added to the water residing inside. As high salinity water sinks to the bottom due to the force of gravity on density, it creates a steep salinity gradient, where the water below is saturated, while in an ideal situation the top layer is unsalted (2). As the entire pool is heated up together by the sun, convection currents do not surpass the salinity gradient, and thus heat from the bottom does not convect up and gets lost in the atmosphere (3). The figure below shows all the major processes that goes on in a typical solar pond.
(1)
The heat trapped below can be transferred and used in cities for use, and this way, harnessing the renewable energy of the sun, we cut down on fossil fuel usage and its harmful aftereffects.
An idea I can think of is possibly installing these in rooftops? Instead of wasting money on heaters and boilers, the solar pond may indeed be a solution. There seems to be however some maintenance complications, like the crystallizing of salts and eventual evaporation of the water (2), rendering this idea not too feasible, but I believe this development may only be in its infancy, and we thus have to rely on great, bright engineers, to solve these sticky issues for us.
Meanwhile, re-read paragraph 1 and REPENT!
References
-
González, D., Amigo, J., Lorente, S., Bejan, A., & Suárez, F. (2016, April 05). Constructal design of salt-gradient solar pond fields. International Journal of Energy Research Int. J. Energy Res., 40(10), 1428-1446. doi:10.1002/er.3539
- Solar Ponds Will Determine the Future of Energy Creation. Solar Energy For Homes. Retrieved 20 September 2016, from http://www.solar-energy-for-homes.com/solar-ponds.html
- Solar pond. Edugreen.teri.res.in. Retrieved 20 September 2016, from http://edugreen.teri.res.in/explore/renew/pond.htm
Hi Mak! Thanks for sharing this interesting idea about solar pond. Do you think it’s more viable and efficient than solar panels? Because I think the solar pond can only serve to provide heat while solar panels can generate electricity which has a wider range of applications. Do we still need this now that solar panels are more and more prevalent and affordable and efficient? And if installed on rooftops, is the pond large enough to provide enough heat for the whole building? Thank you!
That’s a good point you brought up here, that there is an opportunity cost of placing the ponds on rooftops, which is that they take up the space that could be used for solar panels. Yes you’re right solar ponds only are able to produce heat. However in my opinion, one upside of the solar pond may be that it is so much cheaper to manufacture, and the amount of time needed to earn back the sunk capital is way shorter as compared to solar panels.
How to get good topics like this?