What you'll build
Build a fan from recycled materials and control it with Arduino.
Before you start
You'll learn: Switching a big load (a motor) with a transistor and diode, driven by a small pin.
You'll finish: A fan built from recycled parts that the Arduino pulses on and off from pin 9.
Real world: The same circuit runs water pumps, gate motors and fridge compressors — anything too big for a pin alone.
Then try: Power it from a small solar panel, or make it switch on when a room gets hot.
Who does this: Mechatronics or appliance-repair technician — TVET diploma, or a repair business of your own.