With Christmas approaching, families around the world have begun decorating their homes with all manner of twinkling bulbs and flashing lights to appease Krampus, the evil European anti-Claus. Or because it looks pretty. But I digress. While electric bills are known to rise in the winter, an aquarium in Japan has seemingly nipped this problem in the bud by powering a Christmas tree with…an electric eel?

Situated south of Tokyo, the Enoshima Aquarium in Kamakura has taken to utilizing the eels ability to generate electricity when moving to power a two meter Christmas tree. While the power generated isn’t enough to provide consistent light, it is strong enough to allow intermittent flashing.

To further add to its eco-friendliness, Kazuhiko Minawa, who works on the public relations team at the aquarium, says they have added a robotic Santa Claus powered by human muscle. When visitors to the aquarium step on a pad, it generates electricity.

The eel has been around for five years, used in part not just to freak out small children but to promote eco-awareness. While the idea is certainly a good one, you should probably stick with something like solar power over an electric eel to be a little more green.