Staff at the Galloway Hydro Scheme could go on strike.
Members of the Unite union at Glenlee power station are being balloted over industrial action following a pay dispute with operators Drax Hydro.
The union has rejected an eight per cent pay offer, calling for a deal closer in line to the rate of inflation at 13.4 per cent.
Unite general secretary, Sharon Graham, below, said: “Energy workers’ pay is lagging well behind the eye-watering profits being made across the sector.
“Drax’s parent group is awash with tens of millions in profit. Yet, Drax Hydro workers have been offered what amounts to a significant real terms wage cut, this is totally unacceptable.
“We will fully support our members in their fight for better jobs, pay and conditions.”
The ballot among staff at Glenlee, as well as their colleagues at Stonebyre near Lanark and Cruachan at Loch Awe, began on Wednesday and closes on February 22.
Drax Hydro normally supplies businesses, with homes only being powered if there is a shortage in the system.
Elaine Dougall, Unite regional co-ordinating officer, said: “The pay offer on the table by Drax Hydro doesn’t come close to meeting the fair and reasonable demands of our members.
“The Drax Group, like all energy companies, is benefiting from price hikes across the board. If there is no improved wage offer then our members are set to take strike action in the coming weeks.
“This could directly hit energy supplies to Scottish businesses. Drax Hydro must explain why they are prepared to jeopardise the precarious position of many Scottish businesses rather than working to resolve this dispute.”
A Drax spokesman said: “We have put forward a fair and competitive pay settlement which rewards our valued colleagues and is significantly above the national average.
“We will continue to work with the unions to find a resolution which avoids strike action at our Scottish hydro power stations and ensures the long-term sustainability and success of the business.
“Drax’s hydro operations play a critical role in energy security and we plan to invest billions of pounds in our UK renewable energy projects this decade, including the expansion of our Cruachan pumped storage hydro power station, creating and supporting jobs in Scotland.”