This small DC motor will run on 0.5 to 3V DC. This motor requires approximately 100mA start-up current, and runs at about 50 mA with no load. Low torque, high rpm's.
Dimensions: 1" motor diameter X 1.5" long, 2 mm shaft diameter.
Works well with the solar panels shown below:
Dc Motor 0.5V To 3V For Projects