Desalination Guide: How It Works, Home vs Industrial, Cost, and Impact
Quick Answer Desalination removes salt from seawater or brackish water to make it drinkable. The two dominant methods are reverse osmosis (pushing water through a semi-permeable membrane under high pressure) and thermal distillation (boiling seawater and condensing the fresh vapor). The key numbers: Industrial plants produce huge volumes but cost $1-$3+ per 1,000 gallons (about $0.001-$0.003/gallon operating cost) and use 3-13 kWh per 1,000 gallons Home/portable desalination is far more expensive per gallon — a survival desalinator is really for emergencies Environmental costs (brine/discharge, energy use, marine intake) are the major drawbacks at scale Bottom line: Desalination makes sense at industrial scale for coastal cities, but for almost every homeowner it’s far more economical to drill a well, harvest rainwater, or use an atmospheric water generator in a humid climate. ...