US scientists build ‘fog guitar’ that strums water from thin air

Researchers at Virginia Tech have developed an innovative atmospheric water harvesting device called the "fog guitar," which significantly improves upon traditional fog collection methods. Traditional fog nets, used for centuries, suffer from design limitations such as clogging due to small holes and inefficiency from large holes letting droplets pass through. In 2018, the team introduced the "fog harp," which replaced horizontal wires with vertical fibers to increase water collection efficiency by two to seven times. However, the fog harp faced a critical issue: under heavy fog, surface tension caused the vertical fibers to tangle and clump, reducing performance when water was most abundant. To solve this, the researchers created hybrid "fog guitar" designs that reintroduced a limited number of horizontal supports—akin to guitar frets—to prevent fiber tangling while avoiding clogging. By testing seven variations with different numbers of these "frets," they identified an optimal configuration that balances the prevention of tangling and clogging, maximizing water collection efficiency even in dense fog.