The company says they reduced the voltage due to problems on electrical cables supplying power to the area.
Con Ed is asking customers to turn off non-essential electrical appliances to help reduce electricity usage until the equipment problems are resolved.
The affected areas include Coney Island, Manhattan Beach, Seagate and Gravesend neighborhoods.
The area is bound by Gravesend Neck Road on the north, Shell Road and Coney Island Creek on the west, East 15th/East 16th streets to Sheepshead Bay to the east and the Atlantic Ocean to the south.
Some 27,000 metered customers are affected.
Company crews are working to repair the problems.
The equipment problems in the area have no effect on the rest of the Con Edison system.