Greenpeace has urged European regulators not to allow any extensions to the intended lifetimes of nuclear power plants because of safety risks.
The campaign group said that of 151 operational nuclear reactors in Europe, excluding Russia, 67 are more than 30 years old and 25 more than 35 years.
Seven are older than 40 years, the study found.
Jan Haverkamp, one of the report’s co-authors, said: “By asking to extend the lifetimes of their old and deteriorating nuclear power plants, the big European electricity companies are simply hoping to extract more profit from their nuclear cash cows, while leaving Europe’s citizens facing greater risks and enormous consequences in the event of an accident.
“The lifetime extension of European nuclear reactors would lock us into an old and dangerous energy source for decades.
“When they meet to discuss energy policy at a summit in late March in Brussels, European leaders must seize the opportunity to end the age of risk and pollution and support a binding renewables target to hasten the age of clean energy.”
Greenpeace said reactors that are older than their initial design lifetime should be closed immediately, and called on European nuclear regulators not to grant any lifetime extensions beyond that point.