Desertec failed due to geopolitical considerations (basically the Europeans didn’t want to have their next energy sourced from a region outside their control and therefore stopped funding the project)

Turns out a large excellence cluster technical university can do the same and bring down an entire campus for 2 days. Everything is in one big intranet, has main lines with high throughput routed to a large network node and one backup line from the local internet provider. It killed the main lines and thousands of staff plus some tens of thousands of students were connected through a household class fiber connection. That was fun :)