Making a Complaint
If you experience difficulty with your bill, your connection to the electricity or some other issue relating to your electricity supply you should first try to resolve the issue with your supplier or network operator.
What you do if your complaint is still not resolved to your satisfaction?
If you are unable to resolve the problem following completion of your supplier or network operators complaints process, you can contact the Commission for Energy Regulation (CER) who offer an independent complaint resolution service. Please note the Commission can only investigate unresolved complaints where a customer has exhausted the complaints processes provided by their supplier or network operator.
CER also deals with disputes concerning the ESB Customer Supply Charter and ESB Networks Customer Charter.
For guidance on how to make a complaint to CER please visit their website at CER - Complaints Procedure 
or, if you wish to write, email of phone, they can be contacted at:
Commission for Energy Regulation
The Exchange
Belgard Square North
Tallaght
Dublin 24
Tel: 1890 404 404
Fax: 01 400 0850
email: cct@cer.ie
Online: http://www.cer.ie/