The 300 MegaWatt coal plant generates about 20 percent of the daily demand of energy of about 30 GigaWatt hours (millions of units).
The base load Chinese built plant was expected to have 80 percent plant factor, but has been cutting out intermittently.
On Sunday and Monday, the CEB provided power running down its remaining hydro reserves to about 24 percent, amid one of the driest years in a decade.
Hydro plants are needed to maintain a night peak.
The CEB started three hour power cuts from today, ending more than 10 years of power supply with no official rationing.