Originally Posted by telekinetic

You guys are looking at this all wrong. Solar planes don't replace cessnas or jumbo jets. They replace communication satellites and cell towers, research the weather, map the country, track herd migration...anything that requires altitude, duration, and persistence, but not speed or payload. They are completely impractical and unnecessary as passenger craft, as having passengers who embark and disembark allows you to just fill up on fuel (be that fuel a battery charge or gas or whatever), but for persistence and endurance, their sustainability is unmatched except by satellites and maybe blimps.