ESB crews were tonight bringing in stand-alone generators to restore power to thousands of homes after a fire at an electricity sub-station.
An early-morning blaze at an ESB sub-station in Clondalkin, Dublin, left up to 15,000 houses without electricity in the area.
Supply was cut off while firefighters brought the outbreak, on the Ninth Lock Road, under control.
While the ESB restored electricity to most customers by this afternoon, several thousand remained without power.
ESB spokesman Mr Kevin MacDermott urged customers in neighbouring areas to limit use of non-essential appliances.
"We are asking customers in Clondalkin, Palmerston, Lucan and Ballyfermot to reduce their power output," he said.
"We are asking them not to use things like tumble dryers, washing machines or anything that isn't essential - that will help us share out the power."
Mr MacDermott said generators were being brought in to help boost power in the area.
"We are confident we will have power back to all customers by the evening," he said.
Firefighters were called to the blaze in Clondalkin, in the west of the city, at around 6.30am.