Originally Posted by Hummeth
"Reelight are designed to deliver their own energy source. As there is no friction involved in the electric generator, the electrical energy is generated by the cyclist effortlessly."
This is not possible. Maybe close but they should reword those sentences.
There is no friction, so they are not lying there. However, there is the counter electromotive force and so there is effort to produce the electricity due to that.
I could make those easily with an led, copper coil, magnet, and a capacitor (might need a resistor too).