How does desalination turn seawater into drinking water?

The answer

The most common modern desalination method is reverse osmosis (RO), which forces seawater through semipermeable membranes with pores small enough to block salt molecules but allow water molecules to pass through. This requires high pressure (55–80 bar) and significant energy - about 3–4 kWh per cubic meter of freshwater produced. Over 21,000 desalination plants operate worldwide, with the largest (Ras Al Khair in Saudi Arabia) producing 1 million cubic meters of freshwater daily. Energy costs remain the main barrier, driving research into solar-powered and more efficient membrane technologies.