What is a passive solar still?

Solar distillation is a process that uses the sun's energy to evaporate freshwater from brackish or sea water. It's a low-cost, low-maintenance system that can be used at the household level or scaled up for larger populations. Solar distillation is analogous to the natural hydrological cycle. It uses an apparatus called a solar still.  Some steps in the solar distillation process: Sunlight penetrates the glass cover and heats the saline water. The water absorbs heat and slowly reaches high temperatures. The heat causes the water to evaporate, cool, and condense into vapor. The... Show more

Solar distillation is a process that uses the sun's energy to evaporate freshwater from brackish or sea water. It's a low-cost, low-maintenance system that can be used at the household level or scaled up for larger populations. Solar distillation is analogous to the natural hydrological cycle. It uses an apparatus called a solar still. 

Some steps in the solar distillation process:
Sunlight penetrates the glass cover and heats the saline water.
The water absorbs heat and slowly reaches high temperatures.
The heat causes the water to evaporate, cool, and condense into vapor.
The contaminants are left behind.
The vapor rises and collects on the cling wrap.
The rock on top helps the vapor collect and drip into the clean container in the center. 

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