The Ministry of Electricity said on its website on Sunday that the condition of the load had reached a critical level.
This comes after the Egyptian state television had called on citizens not to use high-consumption household appliances from 6pm to 11pm.
Many experienced power outages multiple times throughout the day.
The Sunday power outages coincided with a spike in temperatures, causing a rise of consumers using air conditioning, which is the main driver of household electricity comsumption.