1 watt conducted power, 4 watts EIRP. For most of the world, the ETSI limit is 100mW EIRP.

https://www.ecfr.gov/current/title-47/chapter-I/subchapter-A...

1 watt? With beamforming to increase the energy density you could run a tiny microcontroller off of that.

This is about radiated power in any direction not exceeding what you would get with an omnidirectional 1W antenna.

So beamforming under these rules lets you use less input power for the same directional power. But it doesn't let you bundle all your power into a single direction.

Which is probably good, as 100mw focused in a very tight beam could cause considerable mischief.

Yes. Beamforming for the receiver, tho, is highly beneficial. MIMO does that for you. The previous poster is correct, the EIRP must not increase when antenna gain does; you have to turn down the wick on the TX.

600 watt is a microwave oven.

A microwave may generate waves with many hundreds of Watts but the FCC limits the allowed leakage to ~the same effectively radiated power as they do Wi-Fi in the 2.4 GHz band.