How to Make a Generator From an Exercise Bike

How to Make a Generator From an Exercise Bike. Convert virtually any exercise bike into a generator of electricity to power small appliances or recharge batteries. This can be accomplished in a number of ways, but the simplest and most practical is by attaching a rubber serpentine belt between the wheel on the bike and the shaft on whatever generator is chosen to produce the electricity. Using a few common tools, attach the generator to the bike frame, mount the belt and, ultimately, start saving on electric bills.

Use energy from an exercise bike to generate electricity.

Things Needed

  • Stationary exercise bike
  • 12-volt DC generator
  • Deep cycle battery
  • Volt meter
  • DC adapter
  • Power inverter (optional)
  • Metal L-brackets
  • Bolts
  • Power drill
  • Drill bits for metal

Step 1

Remove any resistance mechanism, leaving either a freely rotating gear or a wheel (which now becomes the "flywheel"). Cut a groove into the edge of the wheel using a router. Hold the router against the outer rim of the wheel and, using human power to pedal the bike and turn the wheel, cut a 1/4 to 1/2 inch groove, deep enough to hold the belt.

Step 2

Drill holes in the frame for the L-brackets, then bolt the brackets to the frame. Bolt the alternator to the brackets with the pulley wheel on the alternator lined up with the flywheel on the bike. Run the rubber serpentine belt between the generator and the flywheel. If the belt slips at all, adjust the tension by loosening the screw that holds the generator to the mounting bracket, pulling the generator to increase tension and tightening the screw.

Step 3

Attach the DC adapter to the generator, connecting the "hot" wire to the positive pole and the "neutral" wire to the negative pole. Any device with a charger designed for use in a car will work with this configuration. If alternating current (AC) is required for powering a home appliance, a power inverter must be connected as well. Connect the inverter by attaching the "hot" wire from the generator to the positive pole on the inverter, the "neutral" wire to the negative pole, and the ground to the ground. If opting to store excess electricity, then connect the generator to the battery with the "hot" to positive, "neutral" to negative, ground to ground. Optionally, attach a volt meter to monitor how much electricity is generated while pedaling. The volt meter may be attached for easy view to the handlebars on the bike using mounting brackets available at any hardware store. Again, attach the "hot" wire to the positive pole, the "neutral" to the negative, and ground to ground.


  • A pedal-powered generator is now available from some manufacturers.


  • Dan's Workshop: Exercise Bike Generator
  • Alternative Energy: Pedal Powered Electricity Generator from Windstream
  • Sustain Lane: How to Convert an Exercise Bike Into an Energy Bike