Viscosity Stabilized Solar Ponds

Demonstration salt gradient solar pond. Fourth semiannual progress report, November 1, 1978-June 30, 1979

“…Finally, the alternative of viscous stabilization has been presented recently (Shaffer, 1976); in this approach, convection of the upper region is prevented by addition of primarily organic polymers to gel the pond and maintain it statically stable in the presence of a temperature gradient. Research in this area is proceeding with the testing of gelling substances in small laboratory tanks (Atwater, 1978).…”

Solar pond powered liquid desiccant evaporative cooling

“…Moreover, the salt gradient layer requires constant maintenance. To overcome such difficulties, Shaffer [154] proposed a hybrid solar pond that contains a transparent polymer gel to act as a non-convective layer or zone. The polymers used in such pond should have a high transmittance for solar radiation, high efficiency of the chosen thickness and should be able to operate at temperatures up to 60 0 C. Starch, Gelatin and Arabic gum can be suitable materials to use in viscosity stabilized solar ponds [155].…”

New comprehensive investigation on the feasibility of the gel solar pond, and a comparison with the salinity gradient solar pond

“…The salinity gradient zone of the SGSP was replaced with a viscous and transparent gel layer [23]. Disadvantages of the SGSP have been identified by Shaffer and Dorothy [24]. They suggested that salt diffusion through the pond's layers affect the pond's stability.…”

“…Water is the preferred liquid for the storage layer because it has a high heat capacity and suitable transparency. To overcome or decrease the concentration gradient influences and convection, a polyacrylamide polymer layer has been suggested instead of the NCZ [24].…”

“…For the gel pond, most construction costs are similar to those of the SGSP, except the cost of the salt, because in the gel pond a gel layer has been used instead of the NCZ in the SGSP. LCZ in the gel pond (kg/l) For an approximate estimate of the capital cost of the gel pond, Equation 23 can be rewritten as:(24) where and b are the percentages of the LCZ and the gel layer thicknesses to the total thickness (LCZ + gel), is the concentration of the gel material in the gel solution, the solvent used for the gel is mostly water, so the additional cost of the new chemicals isneglected, and water is considered to be the solvent in the present calculation. Equation 24 illustrates that the capital cost of the gel pond depends on four factors: the salt concentration of the LCZ and its thickness as a percentage (represented by )), the percentage of the gel thickness (represented by ) and the gel concentration.…”