ABC affiliate WLOS reported the substation Swannanoa River Road, powering customers in the Biltmore Village area, is surrounded by rubble.
Some of it is embedded in the structure.
"We've never had anything like this. Never. I've talked with guys who have been 40, 50 years in this field, each one of them says never before," Duke Energy spokesperson Bill Norton told WLOS.
He said the substation will need to be torn down and rebuilt over the next three to four months. The energy company will be installing a temporary substation in the meantime.
A majority of those without power should expect it to be restored by the end of Friday.
Norton told WLOS it has been difficult to give restoration timelines. There are areas Duke Energy has not been able to access after the hurricane.
This is not the norm for most natural disasters, he added.
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