Solar Power Satellites: A Visual Introduction
wired.com
wired.com
Turns out space is big; things don't go anywhere if you just put them nearby. So no need to have buildings to store them.
And thousands of independently-operating solar cells would work as well as a big rigid frame. Why not have each cell in a swarm beam its energy to a single large transmission facility? No need to wire-and-bolt them together.
Probably its improvements in compute power that made this inconceivable decades ago. But now it seems obvious.