A Union Disputes Committee in a statement released through the ESB group of unions says all their power will be turned off at 8am on Monday week if a solution is not found to the pension dispute.
The ESB group controls 40% of the single electricity market.
Unions and management at the ESB are currently attending talks with the Labour Relations Commission at an undisclosed location.
The Government said contingency plans are in place in the event that the strike goes ahead, but it has not said what they are while the unions said that due regard will be had for public health and safety.
A statement from the Union Disputes Committee said: "Due to ESB's false accounting and statement of intent regarding the staff's Defined Benefit pension scheme a strong mandate for industrial action has been received from a ballot of the staff affected.
"The Unions that comprise the ESB Group of Unions have formed a Dispute Committee to execute on the ground the mandate of the membership and have decided the following:
- The industrial dispute to commence at 8:00 am on Monday 16 December 2013 will take the form of an all out dispute (full withdrawal of labour and the placing of pickets) involving all unionised staff who are members of the Defined Benefit pension scheme.
- All ESB generated power will be off the bars from 8:00 am on Monday 16th December.
Due regard has, and will continue to be, given to matters concerning public, staff and environmental health and safety. Therefore, where applicable and to be decided by the Dispute Committee, emergency cover for fault and repair services will be provided."
The Minister for Energy and Communications Pat Rabbitte said there isn't any threat to the pensions of any worker at ESB.