The Ceylon Electricity Board (CEB) said today the power outage experienced countrywide on Sunday night was caused by an increase in the power supply amid a major drop in the demand.
The demand for power had dropped because of the prevailing wet weather conditions and the long weekend.
The CEB said the maximum peak demand during night on an ordinary working day was about 2,100 MW and declining to about 1,100 MW after midnight. During weekends, the maximum peak demand at night was around 1,900 MW with the minimum demand around 950 MW.
However, on this Sunday due to the Poya day and the long week-end and the prevailing bad weather conditions, the CEB said the total system demand has further decreased and it was around 1,775 MW during the night peak which is a significant reduction from the usual.
“Furthermore, around 00.53, the demand was further reduced to around 940MW which is very much less than the usual 1,100MW during midnight and was dropping further. It is strongly suspected that a rare unstable situation had arisen resulting in the power outage,” the CEB said.
It said technical investigations were being done to establish the exact cause of the incident.
The CEB System Control Centre began restoration work immediately and full power was restored by Monday morning.