A Bicycle Powered Generator produces electricity and can be used for different ideas. See the various possibilities presented here in the following videos.
The bicycle is connected to the generator which is driven by the human-powered bicycle. The electricity can be used in different ways for example to light up a bulb. You can produce 150 to 200 Watts or more, going at a moderate pace.
You could get some exercise while generating energy at the same time and put it to good use. The generated electricity is inexpensive, easy, and can power anything. Bicycle generators are easy to build, just get the right components.
It is important to be able To store energy because you don't pedal all the time. The electricity will be stored in a battery and can be used later for example to light a bulb.
You need:
Bicycle Training Stand
400 Watt Inverter for converting DC to AC power
12 Volt / 30 Amp Charge Controller to prevent overcharging the battery