I have an easement across the middle of my property in favor of PGE for underground electrical that services my neighbor's property. My neighbors property was once owned by the daughter of my properties previous owner. When the daughter was building her house, my properties previous owner allowed her to dig the electrical across my property to connect to an existing PGE power pole on 3rd neighbors property. There is no easement for PGE or anything else across the whole width of this 3rd neighbors property to connect to the pole. The daughter dug, installed line, and PGE connected to pole while 3rd neighbor was out of town on vacation. TO boot, there is another easement for power across the front of my property that was to service my neighbor, but it was much shorter for them to go across the middle of my property and then have my properties previous owner give an easement for PGE across my property after the fact. My question is, can my 3rd neighbor do something to get this power line shut off since it goes across his property illegally, and then I can force the neighbor to use the correct easement instead of the one across the middle of my property.
Maybe. It depends on how long ago the landowner who gave permission sold the property.
When that person gave a "license" (meaning permission) to PG&E to put in the line, it could have revoked the license at any time. For so long as that person owned the property, PG&E acted under that license, so that the 5-year prescriptive easement clock had not started running.
In many states, a conveyance of a property upon which one person has a license revokes the license. In California, the question is unsettled. If the person who granted PG&E revoked it by selling it to someone else, then the 5-year clock started running at that time (assuming everyone knew about PG&E's easement. I recognize it is underground).
Thus if the property was sold more than five-years ago, you may have a problem. But maybe not. You should definitely consult with an attorney to determine what rights you may have.
An easement is a right to enter or use someone else's property for a specific reason. It remains in force even if the property is sold and is also transferable.