Fire crews tackled a blaze at the defunct Longannet power station in Fife.
Eight appliances were sent to the Kincardine power plant, which closed down in March 2016, after fire broke out in a relay room at around 6.30am on Monday.
Fire alarms were triggered in the building, which alerted emergency services.
There were no reports of any casualties.
The control room at Longannet.
The Scottish Fire and Rescue Service said crews used breathing apparatus and carbon dioxide extinguishers to bring the blaze under control.
It is understood the fire was not thought to be suspicious.
However, an investigation into the cause is to be carried out.
A spokesperson for ScottishPower said: “A small fire broke out this morning in the station’s telecommunications room, the fire brigade attended and the fire was contained quickly.
“A full investigation will be carried out as to the cause.”
Crews took until around midday to contain the incident. Two appliances were still at the scene on Monday afternoon.
Closed two and a half years ago, Longannet is in the process of being decommissioned.
There is still a team of workers on site to oversee the decommissioning process.
