Could water evaporating provide power?
Yes. Biological systems are known to convert energy generated from the evaporation of water confined within nanoscale compartments into muscle-like mechanical work.
Researchers Create Evaporation-Powered Motor article tells that scientists designed shape-changing engineered composites of bacterial spores and a polymer that used an evaporation-driven process to power locomotion and generate electricity.
Evaporation-powered Motor and Light article gives some more details on: Scientists at Columbia University have effectively harvested energy from evaporation in the environment to drive engines that start and run autonomously when placed near a water surface. Article also tells that this Evaporation-powered Motor uses bacterial spore-polymer composites to harness energy from evaporation to power locomotion and generate electricity. By harvesting the energy from water evaporation in the environment researchers demonstrated self-sustained power generation from engines placed at air-water interfaces. These evaporation-driven engines could power robotic systems, sensor, devices, and machinery.