High-efficiency atmospheric water harvesting enabled by ultrasonic extraction

Atmospheric water harvesting technology, which extracts moisture from ambient air to generate water, is a promising strategy to realize decentralized water production. However, the prohibitively high energy consumption of heat-induced evaporation process of water extraction hinders the technology deployment. Here we demonstrate that vibrational mechanical actuation can be used instead of heat to extract water from moisture harvesting materials, offering about forty-five-fold increase in the extraction energy efficiency. We report the energy consumption for water extraction below the enthalpy of water evaporation, thus breaking the thermal limit of the energy efficiency inherent to the state-of-the-art thermal evaporation and making atmospheric water harvesting technology economically feasible for adoption on scale. Water can be extracted from the atmosphere via adsorption-evaporation or dewing, but these methods require prohibitively high energy use. Here, the authors report a forty-five-fold increase in energy efficiency via ultrasonic extraction, making atmospheric water harvesting technology economically feasible for large-scale adoption.