The problem with this, if you follow the modern materialistic sciences, is that what you are draining comes from some place.

Like the cell towers, the wifi modem and other people's cell phones.
Most of it isn't ambient, else wifi wouldn't work.

This is the reason that putting fluorescent tubes up in barns near high power lines is illegal. The tubes glow just from the electric perturbations in the space. However, it does put a drain, a resistance load on the power lines.

But, i do not believe in modern materialistic science.