Power is due to be restored to Santorini by Wednesday night, local authorities said.
Mayor Nikos Zorzos said on Wednesday morning that power was being gradually restored to the island.
A fire that broke out at a power station left the southern Aegean island without electricity for several hours.
The fire started at a power station in Monolithos, some 9 kilometers southeast of Fira, at around noon and was doused before it could cause major damage or injuries.
A navy vessel and a passenger ferry were dispatched to carry two power generators to the island for use until the power station is fully operational.