This is regarding the discussion of Nikolai Tesla’s crazy “broadcast power” plan.
What’s the deal with broadcast power?
I actually know a bit about this. Broadcast power is real and works, but only in a VERY specific setting, and it has some significant problems.
How does it work?
Well, the concept is getting radio signals (usually microwave) to produce a longitudinal “standing wave”. The method for doing this is relatively simple: You put a transmitter in the middle of a Faraday cage.
A Faraday cage, for those who didn’t pay attention in high school physics, is a sphere of wire mesh that grounds out electrical fields. In addition – and importantly to our discussion – a Faraday cage can be tuned to reflect particular frequencies of EM radiation by ensuring that the mesh is significantly smaller than the wavelength of the desired signal.
So, you stick a big transmitter in the middle of a Faraday cage that’s tuned to reflect that particular frequency, and beam out microwaves (not the kind that heats water, preferably). The microwaves rebound off the inner surface of the cage, and if the system is set up right, the volume inside the cage is flooded with energetic waves. Once you reach equilibrium, the transmitter starts acting as a receiver as well, the energy gained from incoming, absorbed microwaves equals the energy being pumped out, and the system stops sucking up extra power from the generator (theoretically; there’s always leakage, of course).
Now you bring in an antenna of the proper tuning to pull those microwaves. You plug in one end of a circuit to the ground (or whatever structure you’re using as the electrical ground) and the other to the antenna, and you get DC power. Because the antenna is now absorbing microwave power from the air, the amount received by the transmitter is reduced, and you read a power drop (the same as you would read a power drop when somebody plugs into the output from a traditional generator). Ta-da! Electricity from the air.
Any piece of wire of the right size can be used as a receiver, so you can get virtually any device to work by plugging it into the antenna and electrical ground.
Tesla’s crazy plan was to use the Ionosphere of the earth as the Faraday cage, and use multiple transmitters to pump the entire atmosphere with microwave power – anyone, anywhere on the planet, could plug in and run DC current.
Now, the downsides:
His plan wouldn’t have worked anyway, because the ionosphere is a very imperfect cage. It would leak horribly, leading to power loss.
Moreover, the advent of modern technology makes even small-scale use of the system totally unfeasable. Remember, ANY piece of wire can become a power antenna. A computer, unless it was carefully hardened against EMP, would have thousands of tiny antennas inside sending spurious power through its systems – it would burn out instantly.
And as mentioned in the column, nobody really knows what the effects would be of actually living in a massive microwave shower; it probably wouldn’t be very good for you.
In all, it works, but it’s just a curiosity. It’s of no use in the real world. Anyway, how would you bill people for usage when you can’t tell whose antenna is picking up how much power?
