But technically do you think this adversely effects the electricity company? If not, it's just overspill.

I'm not an RF expert, but I believe this is a matter of near field vs far field.

In far field (like typical radio broadcasts), there's no "coupling" between the transmitter and receiver so the former just radiates its power and cannot distinguish whether it's being received.

In near field (RFID etc.), there is a coupling and the transmitter can definitely tell whether a receiver is present and absorbing the power.

Thus, and IANAL either, but IMHO harvesting from the near field definitely seems more like stealing, while the far field doesn't; is it stealing to effectively recover "waste energy" that would otherwise just be dissipated uselessly, and wouldn't cause any measurable increase in consumption from the power company?

Since they operated directly under the wires, I think this is clearly a near field.

Generating power from far fields does not seem likely to get any meaningful yield. I remember my father showing me how to build a passive radio receiver using a strong sender nearby and it worked. No other power source involved but you could listen to the (weak) output. So in theory possible, but not really useful.

The earliest radio receivers that I built as a kid were entirely passive, eg a tuned circuit and a diode, and the captured energy was enough to drive a ('crystal') earpiece. I was many many (tens/hundreds of) miles from the transmitters.

This is exactly it. If you were to do this 'at scale' you'd end up having to generate more electricity to compensate for the losses, so it's clearly theft. Whether your grid coupling uses a capacitor or an inductor isn't relevant, clearly you are taking energy from the grid and is the thing that matters.

Indeed, and thus I stand by my original point, though downvoted!

The UK Wireless Telegraphy Acts made it illegal to listen to something that you weren't meant to by fiat without need of any proof of harm AFAIK, so there could easily be random laws in various places outlawing this extraction of power that has to be made up by other generation, even if small.

You generally aren't allowed to extract even small amounts of power from the system unmetered with a wire either, without specific permission.

One of the comments says, it does effect the electric company (why shouldn't it, energy does not come out of nowhere) and they can meassure it.

"Velemu says: There was one case in Finland in The 90s, where someone did this to power their summer cottage. When Power company found, where the extra parasitic load came from, they sued the guy to hell and back again. This kind of load is actually actively measured by Power companies, since it is also used to find other failure modes on powerlines, and is easy to detect. Just don’t do it…."

Tim Hunkin's cartoon encyclopedia (from the 80s) mentions a conviction in Canada. https://www.rudimentsofwisdom.com/pages/power%20lines.htm

Some other cases mentioned here: https://www.industrytap.com/electromagnetic-harvesters-free-...

I think the main reason the electricity companies discourage this is the hazard it presents. The 'collector' is basically a current transformer, which means:

1. If the outputs of the 'collector' go open circuit (because the rectifier/capacitor/whatever dies) the voltage at those terminals is going to rise theoretically towards infinity - insulation breakdown and discharge will occur which is likely to result in a fire.

2. The current generated by the 'collector' is going to be proportional to the transmission line current; if a ground fault occurs on the line the current in the collector winding is going to spike up to some silly level; that will probably result destruction of whatever is connected to the collector outputs and subsequently a fire.

Imagine the alternate history political and legal mess if PG&E had found such a setup in proximity to the start of the fires back in '21 and '22.

Technically, yes it does adversely affect the electricity company. It's not 'just overspill', that's how electricity moves from one place to another.