I couldn't find it, but I think French courts have a jurisprudence on this already (unless it's an internal urban legend from EDF, who knows): one day a EDF (Fr

I couldn't find it, but I think French courts have a jurisprudence on this already (unless it's an internal urban legend from EDF, who knows): one day a EDF (French electricity producer) who was living close to a power line built an “antenna” like this to harvest electricity, and he bragged about it. EDF sued, and the defendant claimed that he was just collecting electromagnetic waves that were leaving anyway, but EDF and the experts summoned by the court argued that it wasn't the case and that he was in fact draining power. He was found guilty because he was doing that on purpose, and even if he believed it was doing no harm, he should have checked beforehand especially since he was working in the field he should have been able to know or at least get the information about what was going on if he checked.