Self-powered Automatic Faucets,This faucet features a non-contacted design. The controller switches on the solenoid valve when the hands are close to sensor. Then, the water flow goes through the generator, and the turbine rotates to generate electricity. If the sensor detects hands stay and the solenoid valve keeping work; if the sensor detects no hands stay and it will closed to the solenoid valve. And the electricity stored becomes the main power resource.