I have to agree with Warren on this one. There isn't much of anything novel about this. It certainly isn't harvesting energy from air!! It's just using an electromagnetic field to drive current in a secondary coil. Another name for it would be a transformer. I also agree that it's technically stealing. If you created a big enough coil to encompass the powerline, or any wire carrying current, and then use the induced current to power a load you will create a load on the primary line. It's just a very small transformer creating a negliable load. This basically no different than plugging in your cell phone at work. Are you using power for or from someone else? YES. Will you get fined or fired for it? Probably not. Change the quantity and scale, however, and the free ride will end.
Harvesting energy is in effect creating a parasitic load on an electrical field
(be it RF, low frequency, etc). A normal radio receiver is a load on the transmiiter, its just too small to be significant. If you designed a really large receiver designed to trap energy, you'd make a measurable dent in the radiation pattern. The radio transmitter would not broadcast as far past your direction. If your load is small enough not to be noticed... it might appear to be ~free~ power.
A windmill generates 'free' power because no one paid to make the wind blow... and no one was otherwise harvesting the wind. If you built enough windmills you would indeed (eventually) run out of wind. Only when the load is insignificantly small does it make sense to consdier it 'free'.
A better idea is to harvest energy that is otherwise thrown away, or that people are paying to get rid of. Using (for example) waste heat from a cooling tower to heat homes is an example.
Thanks for your opinion, warren. I think there are some that may feel differently about this, perhaps even believe that electricity should be a free resource. But I will let them weigh in on that! Appreciate your reading the article.
Actually, people have been prosecuted for stealing energy frmo the power company on lines that ran through their own property. You can't even take water out of the ground on your own property without Dear Leader's permission. You can't keep airplanes from flying over your own property and sky. Deer that feed on your garden can't be shot out of season. So, just because a power line is on your land doesn't mean you have ownership over it.
So, charging the battery in the article is not right. It isn't even clever or unique.
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