I had this idea for a new solar engine a while back, took a while, but finally uploaded the video, but here it is. In this project I hack a Solar lamp’s brains, the 4 legged YX8018 chip and turn it into a timer. The 2.5V solar panels charge the capacitor. When the capacitor gets abover a certain threeshold (defined by the Diode and resistors across legs 4,3,2), it triggers a discharge of the capacitor, which in turn charges the smaller capacitors across pins 4 and 1 and loads the motor. The circuit was my creation, but Doug’s post @ ez.analog.com definately helped out in the begining. Also took some inspiration from Solarbotics, but the circuits there mostly required 5-6V solar panels, which I didn’t have. I was able to do some 555 timers (without LED flasher) but in the end, this circuit with the YX8018 was the winner, working within a much larger range of lighting conditions.