Nanoscale device generates continuous electricity from evaporating water and some sunlight — paves the path for battery-free sensors, wearable electronics, and more

Researchers at EPFL in Switzerland have developed a nanoscale device that generates continuous electricity from evaporating water, aided by heat and sunlight. This technology, known as a hydrovoltaic device, can work with ordinary ion-containing water like tap water or seawater. The device consists of three layers that harness evaporation, heat, and sunlight to produce stable electrical output. While the power output is small compared to commercial solar panels, the device shows promise for battery-free sensors, wearable electronics, and IoT devices in environments with natural water, warmth, and sunlight. The design allows for independent optimization of each stage and potential scalability in the future.