The massive blackout is the fourth in the last six months as a severe economic crisis plagues the Caribbean country. The Ministry of Energy and Mines, in a statement on social media, attributed the latest outage to a failure at a substation in the suburbs of Havana, the capital.
Heavily suggests they have no spare capacity in the system. All the redundancies are gone, everything is now a single-point failure. Anytime something breaks or needs to go offline for maintenance, there will simply be an outage instead of rerouting through the backup system.