Sunlight Helps Turn Salty Water Fresh 58
MTorrice writes "With energy-efficient desalination techniques, water-starved communities could produce fresh water from salty sources such as seawater and industrial wastewater. But common methods like reverse osmosis require pumping the water, which uses a substantial amount of energy. So some researchers have turned to forward osmosis, because in theory it should use less energy. Now a team has demonstrated a forward osmosis system that desalinates salty water with the help of sunlight. The method uses a pair of hydrogels to absorb and squeeze out freshwater."
Use sunlight to pump water... (Score:4, Interesting)
Already done. Over a billion years ago too.
It's one of the methods plants use to extract nutrients from the soil.
Osmosis does some of the work, but it is also assisted by the fact the water travels up sealed tubes in the plant to the leaves, which when the water evaporates, creates a negative pressure in that tube, sucking more up.
How else do you think a 50m tall tree can push water to the top, overcoming 70psi of pressure?