How to Make a Potato Powered Calculator

Long a science-fair project staple, this potato powered calculator is easy to recreate yourself!

You will need

  • Two potatoes
  • A marker
  • Two pieces of heavy copper wire
  • Two galvanized nails
  • Three alligator clips with wires
  • A low-voltage
  • battery-operated calculator

Step 1 Number potatoes Label your potatoes one and two.

Step 2 Remove battery Remove the batteries from the calculator. Take care to note where the positive and negative terminals are within the battery compartment.

Step 3 Insert nails Insert a nail into each potato and stick a copper wire into each potato, opposite the nail.

Step 4 Connect clips Connect one alligator clip to the copper wire in potato no. 1 and attach the other end to the positive battery terminal in the calculator’s compartment.

Step 5 Create second connection Clip a second alligator clip to the nail in potato no. 2, and then connect the other end to the calculator’s negative battery connection.

Step 6 Complete circuit Complete the circuit by clipping the third alligator clip to the nail in potato one and to the copper wire in potato two. Voila, a working calculator!