Solar Distillation

Solar Distillation,a project work done by final year mechanical students

Surveys show that about 79% of water available on the earth is salty, only 1% is fresh and the remaining 20% is brackish. Considering the immense volume of available seawater, from a purely technical point of view, the potential for sea water desalination is virtually infinite.

At a time when the trend is to move away from conventional fuels and replace it with renewable and environment friendly fuels sources, energy from the sun holds great promises. For use in a small water desalination plant, use of solar energy is more economical than the use of fossil fuels especially in remote areas having low population densities, low rainfall and abundant solar energy. The present work aims at evolving a simple and economic design for a hybrid solar distillation unit.

Design has been carried out by giving keen attention towards its functional and economic viability. The capital cost of the unit is logically proportional to its capacity. Aerodynamic shape design has been made with provisions for forced convection for the rapid condensation/cooling. A mechanical float valve is provided for keeping a constant water level in the still. The attached electronic system controls the internal cooling. Within the temperature difference range of 10-13  ºC between condensing surface and water, an output obtained is about 4 liters/square meter.