SDGE does not hold the landlord responsible for bills that are in the tenant's name if the tenant fails to pay the bill due.The balance for an account will stay in the tenant's name, as long as they have moved from the residence.  In normal situations, it will not be transferred to the owner.

See email from SDGE that confirms this
Dear James Burrell,

Thank you for contacting us. You are responsible only for accounts that
are in your name. If a tenant has an established account then he is
Responsible for his own bills. If he/she fails to pay does not make an
owner responsible unless the owner is on his tenant's account or the
account is in the owner's name.

Please reply to this message if we can be of further assistance.


San Diego Gas and Electric
A Sempra Energy Utility