She said the Tamil Nadu Electricity Board (TNEB) would take efforts to purchase power from the open market till the power shortfall issue was resolved following "unexpected developments".
"Though the government is taking several measures to improve the power situation, unexpected developments in the past four days have resulted in the shortfall of 1,026 MW to the state. Because of these factors, many places are experiencing power cuts," she said in a statement.
The Telangana agitation has badly hit work in the Singrauli coalfields, leading to a 1,100 MW shortfall in power generation at the Ramagundam thermal power station, Jayalalithaa said.
"As a result of this, power supply to Tamil Nadu from Ramagundam has been reduced to half. Similarly, due to floods in Orissa, power supply to Tamil Nadu from the Talcher thermal power station has also reduced," she said.
The Chief Minister said the state was also getting less power from the Neyveli power station, Kalpakkam atomic power station, Kaiga nuclear power station in Karnataka and Simhadri thermal power station in Andhra Pradesh.