Eirgrid has confirmed that three power stations have been closed in recent days due to technical problems.
This contributed to an amber alert yesterday, which lasted from 4pm to 9pm.
An amber alert indicates that electricity supplies are stretched.
The generating stations subject to "forced outages" were Tarbert in Kerry, which accounts for 530 megawatts, Great Island in Wexford with a capacity of 460 megawatts, and Moneypoint 2 in Clare, which has a capacity of 285 megawatts.
Aghada in Cork, with a capacity of 425 megawatts, has been operating at a reduced capacity since yesterday.
According to a statement from Eirgrid, one of the three generators at Tarbert is expected to return on Monday, with two expected to remain out.
It is hoped Great Island and Moneypoint will return tomorrow. Aghada is expected to be back up and running fully tonight.
Whitegate in Cork, which has been out for several months, is expected to return next month.