If the energy captured by a solar pond is to be used as heat, then the efficiency can in principle be 100%. If it is to be converted to work via a heat engine, the fraction that can be converted to work is in principle the Carnot efficiency 1 - Th/Tamb, but in practice closer to the Curzon-Ahlborn efficiency at maximum power output (assuming heat flows proportional to temperature differences) 1 - (Th/Tamb)^1/2. Here Th is the temperature of the hottest (lower) layer of the solar pond and Tamb is the ambient air temperature.
a solar pond based electricity generation plant has efficiency of 5 % and power output of 500mW . if solar insolation is 1000mW/m2 . what is the area of solar pond?????