Pedal-Powered Generator: k-12 Project

IEEE ENCS and Society for Universal Oneness (, a non-profit organization stepped forward to sponsor a high school student initiative. A group of three students from East Chapel Hill High School: Parv Aggarwal, Adrian Randall and Michael Delong were guided by the past Section to design and develop an environment-friendly pedal powered generator. As part of TSA (Technology Student Association) activities, this model taps the potential of human energy and transforms it to DC power; in a process that has no environmental hazards. The project was awarded 1st place at NC State TSA Competition held at Greensboro, April 4-6, 2004 and participated at National event held in June 20-24, 2004 at Nashville, Tennessee. The structure of this device resembles a bicycle made stationary, with a belt connecting the wheel to a car alternator. The alternator is connected to an excitation current source and a load. It is fairly easy to operate.

One sits on the bike, and starts pedaling it at a desired gear (front at 2nd, back at 4th), between 90 to 150 rpm. Because the back wheel is connected via a belt to the alternator, the motion of the wheel is transferred to the alternator’s rotor. Since the rotor’s circumference has a 1: 10.77 ratio with the wheel’s circumference, it rotates at a much faster rate than the wheel. The desired gear ratio and speeds are the most efficient for both the peddler and alternator to generate current. Electricity is generated inside the alternator by an electromagnetism property and then rectified to become DC. This 15 Volt DC output can be used for many purposes. However, it is more efficient and useful to store it into a battery first. Therefore, the team designed a pedal-powered 12V battery charger. The ultimate objective of this project is to explore and set the debate in motion if we can build an environment- friendly powered home: all appliances and gadgets can run off non-conventional electricity produced by solar cells, wind powered mini-turbines and exercise generators. It may mean to replace our current utilities with lower consumption devices.