Capacitor as a Battery to maintain juice for a fan that is powered by a small solar panel.

The resistor you see on the right is actually the fan. It has a resistance of about 11ish ohms. I used one of those AutoCool fans that sits in the crack of your car window to cool it when it's hot out. I recreated this in real life. I simply added a 2.7V 100F capacitor and diode as shown. The fan stays spinning after a full charge for about an hour and a half without any sunlight! Even though the voltage does drop slowly. When the solar panel gets electricity in the circuit, it spins faster and slowly charges the capacitor again. This is my first ever circuit since I started studying electrical engineering. Thanks EveryCircut for your hard work on this simulator!! Setting the voltage to 2V then after a few seconds, setting it to 1.8 will show the capacitor discharging. Until the moment it discharges below the dc voltage. At which point, the circuit will feed more back into the Fan (resistor). You'll notice a Voltage drop on the Diode due to the nature of the Diode. So you must supply around 0.6V or 600mv to get the circuit to operate. Ideally, you would use a low loss (forward drop) schottky diode.

published 7 years ago