Terrestrial solar energy could eventually support extremely large economies and populations

If we are interested in whether Earth's civilization could ever reach various technological milestones, or long run economic output and populations that Earth could sustain, the terrestrial solar energy resource can provide helpful information. Using efficiencies of the best lab solar cells, covering the earth with solar panel platforms could provide a thousand times as much energy as our civilization currently uses, and more than a hundred times the production of the terrestrial biosphere. Historical experience curve and cost data suggest this energy supply could be much cheaper than current energy prices, although with increasing overhead costs as less desirable areas such as ocean platforms and less sunny lands are used. Energy payback times are already under a year for energy-efficient solar in good locations, and have been falling along with prices, so solar energy can power its own construction, and with advanced robotics and AI might eventually grow at extremely rapid rates.