The power cut has affected the PA15 and PA16 postcode areas of Greenock. Scottish Power are conducting a probe into the outage which affected supplies mainly in the town’s central area.
The energy network addressed the issue, explaining there had been no previous notice of such an incidence.
A spokesperson for the company said: “We had no advance warning of this and only became aware of it at 8.57pm.
“Our control centre will attempt to reset the network remotely to restore power in stages, and our emergency response team are on their way to the area to investigate and repair the fault.