> Ground-based solar panels have been getting more cost effective for decades and show no sign of slowing down.

I'm no expert on solar but I thought there was some upper limit on how much power ground-based solar panels can generate per area based on how much energy gets through the atmosphere all the way to ground - and that panel efficiency was approaching that limit.

However, I don't doubt ground-based panels can continue to improve in cost and other metrics and thus exert competitive pressure on space-based solutions.

People are gettingtoo hung up on the radiator math and completely missing the massive input advantage of AM0 versus AM1.5. On Earth you get around 1,000 Watts/m^2 (ideal), but in realtiy shave off 20–25% because of clouds and night time. In a sun-synchronous orbit, you’re pulling close to 1300 W/m^2, and that's 24x7. That is easily a 5x to 6x energy yield advantage per square meter of panel per day, and when you have that much surplus energy free from the vacuum, you can afford to brute-force the cooling problem by dumping massive wattage into active heat pumps to raise your radiator temps, effectively paying for the inefficiency of space cooling with the abundance of space power.

Requirements for power still don't come close to total or practical surface area. If we get to that point, space collectors with microwave beams to the ground are viable.