Christmas lights to decorate trees and facades of houses are a tradition, but also involve the consumption of energy. To reduce waste, someone had the idea to power the lights with alternative energy sources.

One of the most original ideas in this sense is the one I had some years ago by a Japanese aquarium in Kamakura, near Tokyo, which is able to power the lights of his big Christmas tree (more than two meters) thanks to an electric eel.

The mechanism takes advantage of the ability to generate electricity when the eel moves, "capturing" the current with two aluminum plates. It must be said that the current generated is not entirely constant, and the tree lights are flashing randomly and with different intensities depending on how swims eel, but this in this case is a merit given that adds charm the lights.