Interesting, practical talk by Mr Mankin. I'm not sure if John mentioned if these 'pizza box' transmitters will be geostationary? I assume that's the only way to keep the mlocked onto their receiver 'lakes'?
There are a couple of downsides to microwave transmission. My time in the RAF taught me that you don't look into a radar transmitter beam directly or your eyes will suffer (and possibly your genetalia). We used to wear a special mask made of finely perforated metal. This was supposed to protect the eyes. This is the same as what is inside all microwave oven door panels. It is probably down the the power levels how much danger is involved.
The other question is if/ how the tranmission is modulated.
In the past Dr George Carlo did research into the effects of mobile phone transmissions. In those days he found it was actually the form of VLF pulse modulation, which is definitely harmful to our cells, rather than its pure waveform effects.
The majority of 'Safety' rules seem to be based purely on the "heating effect" with no regard to the extremely low frequency modulation. I believe that modern cellular systems are now using a frequency modulation, but it will be still at very low frequencies. Who knows what cellular damage that can cause in the long term? And as for BlueTooth there is zero information on what modulation that uses!! It is considered safe purely because of low wattage/ heating effect. Anyway that diverted us from the great prospects of solar power.
I think for us on the 'compact' islands of UK it is the physical real estate of land needed for these giant 'lake receivers' that might be an issue. As populations grow the housing areas are growing. Farming still needs land. Nature lovers like their open spaces, etc, etc. The further you have to transmit power the more losses it incurs.