Portable solar-powered system produces 1.64 liters of drinking water in 8 hours

A research team from Soochow University in China has created a portable solar-powered device capable of generating drinking water from turbid, saline, oily, and highly acidic sources. The prototype uses an electrothermal evaporation process, where a heating element within an internal layer of the structure vaporizes contaminated water, leaving contaminants behind. The vapor is then condensed into clean water, demonstrating a method to purify water without traditional filtration systems.

The device incorporates two solar energy sources: foldable solar cells that power the electrothermal evaporator and a foldable Fresnel lens that concentrates sunlight directly onto the evaporation surface. This dual approach reduces heat losses and energy consumption by nearly two-thirds compared with conventional electrothermal evaporators. The system achieved an apparent energy efficiency of 93.31% and a water production rate of 69.46 liters per square meter per hour when using concentrated solar energy.

Outdoor tests conducted in January and February 2025 confirmed the prototype’s performance, producing 1.64 liters of drinking water in eight hours using an evaporation surface of 30.72 cm². The system was tested on various water types, including sediment-laden, oil-contaminated, highly saline, and strongly acidic water, as well as real seawater, with samples analyzed before and after treatment.

The researchers highlighted the device’s potential for use in emergencies such as floods, earthquakes, and conflicts where conventional water infrastructure is unavailable. The technology operates independently of grid connections or external fuel supplies, making it suitable for portable water treatment solutions. Findings were published in *Nature Water*, though larger systems and extended real-world testing are still required for further assessment.