The seven activists from Austria, Croatia, Romania, Greece and Bulgaria climbed the tower of the Maritsa 3 plant in southern Bulgaria at dawn and painted "Crime" in large white letters on the tower. Another dozen activists stood outside the plant holding banners saying "Stop fossil crimes", "Future for people not for coal", "End of the age of coal", and "Activism is not a crime".
"When this thermal power plant works, it spews out unorganized emissions, which are untreated gases, and the reason for this is the poor condition of the installation and poor maintenance," Desislava Mikova, one of the activists and a member of Greenpeace Bulgaria, which organised the protest, told Reuters.
Since 2021 the plant has been shut down several times by Bulgarian authorities for exceeding allowed emissions.
European Union member Bulgaria, which produces around 40% of its electricity in coal-fired power plants, pledged to phase out coal by 2038, but activists say the date is too far off and demand the government bring it forward to 2030.
The government's plan to phase out coal by 2038 triggered protests by miners across Bulgaria last week against the both plan and financial packages agreed so far to compensate workers.