Henry Spencer (https://en.wikipedia.org/wiki/Henry_Spencer https://en.wikipedia.org/wiki/Henry_Spencer) a couple of months ago run a presentation of current sta

Henry Spencer (https://en.wikipedia.org/wiki/Henry_Spencer https://en.wikipedia.org/wiki/Henry_Spencer) a couple of months ago run a presentation of current state in space power. Land antennas (rectennas) were in this size, ~5km diameter, made mostly from chicken wire. Cheap, and you can still grow vegetables or anything under it. Not much risk walking under it either. Space antennas are an order of magnitude smaller, ~250 meters (for gigawatt-class power stations). To me, this all seem to need a lot of data and some careful calculations :) .