If you can get onto the enel website www.prontoenel.it using your relatives' codice fiscale and their 'customer number' you'll find a possibility of sending ENEL an e-mail. If you write it in English they'll find someone who can understand it! Maybe you don't even need to register - try the 'contattarci' link if you can find one.

ENEL are one of the least difficult companies to deal with, IMO. The phone is best, if you speak good Italian (and can stand pop music while you are waiting to be connected!) Otherwise it's a nothing little task to delegate to a notaio's office or a geometra, or an estate agent or a neighbour.

We have written to ENEL, ENI to tell them of my Father-in-laws death (sending all documents) after 10 months ENI  sent a new contract to be filled in, but we still have not had an overpayment refund of over €1,000 . ENEL are still sending bills to the deceased!!