Get Your Science On: Chilly Drilly

By manually turning the drill, you can make the white square get warm or cold.

What’s Going On

Heat is a form of energy, and energy cannot be created or destroyed. However, heat energy can be moved around. A Peltier Devices is a form of heat pump. When it get’s cold, it’s really just moving heat away from your finger to the other side of the device.

Specifically, a Peltier Device uses the Thermoelectric Effect, which creates a temperature difference between the two sides of a semiconductor when a voltage is applied.

Materials

  • Cordless electric drill
  • Peltier Device with heatsink
  • Metal handle for crank (we bent a metal bar in a vice)
  • Wires
  • Tape, hose clamp, or zip tie
  • Double pole double throw switch (optional)

How to Build

The easiest way to build this is without a switch. Hook the wires directly from the battery terminals on the drill to the Peltier device. Use the tape or ties to hold down the button on the drill. To reverse the current and make the device get hot or cold, just switch the wires!

If you do want to use the switch to reverse the current, follow the circuit diagram here