A solar still is a simple way of distilling water, using the heat of the Sun to drive evaporation from humid soil, and ambient air to cool a condenser film.
The pure water vapor condenses on the cool inside plastic surface and drips down from the weighted low point, where it is collected and removed.
A detailed economic analysis [3] and a thorough optimisation strategy [4] of PV powered RO desalination were carried out with favorable results reported.
The "reverse-osmosis solar installation" (ROSI) uses membrane filtration to provide a reliable and clean drinking water stream from sources such as brackish groundwater.
Solar energy overcomes the usually high-energy operating costs as well as greenhouse emissions of conventional reverse osmosis systems.
ROSI can also remove trace contaminants such as arsenic and uranium that may cause certain health problems, and minerals such as calcium carbonate which causes water hardness.
[7] While the intermittent nature of sunlight and its variable intensity throughout the day makes desalination during nighttime challenging, several energy storage options can be used to permit 24 hour operation.
Thermal energy storage systems ensure constant performance at night or on cloudy days, improving overall efficiency.