# Pedal Dynamo Generator

Topics: Battery, Direct current, Volt Pages: 2 (473 words) Published: June 25, 2013
Project – Pedal-powered phone charger

CALL FOR SCIENTIFIC AND TECHNOLOGICAL RESEACH PROPOSAL FOR 2013/2014 FUNDING CYCLE PROPOSAL
Students intend to do the project of building a simple pedal-powered cell phone charger to mount on my bicycle. Cell phones are small potatoes in the big picture of energy consumption, but the apparatus to be built could be a very practical concept for those on self-supported bike tours or those living temporarily in situations without electricity. Electronic parts needed

1.circuit board
2.bridge rectifier, 100 V, 1.4 A
3.capacitor, 1000 micro Farad, Radial-Lead Electrolytic, 35 V DC 4.voltage regulator, 7805, +5 V DC, 1 A

Other components
1.cell phone charger
2.12 V 6 W bicycle headlight generator
3.bicycle

Circuit diagram:

How it works:
When engaged, the generator wheel rolls against the bike tire. The motion produces electricity, and the greater your speed, the greater the voltage output. The cord from the generator leads first to the circuit board’s bridge rectifier, which converts the AC to DC. In other words, the up-and-down, positive-to-negative current becomes a steady positive current. Then, the capacitor levels out the DC voltage, producing a steady voltage inflow to the voltage regulator. The voltage regulator is crucial, as the phone only needs five volts to charge, whereas fast pedaling can produce 30 volts or more, which is enough to fry the average cell phone. The regulator controls the voltage, putting a five-volt ceiling on the power entering the phone. Results:

Starting with a dead cell phone, plugged in and placed in a porch, one can spend approximately three hours and 25 kms riding in the streets of say a village to charge it back to full power. An easy speed of only four Kms per hour Is enough to keep the power production at the necessary five volts, and almost as soon as start out, the phone would light up and beep, indicating that it had begun to charge. Even...