The project is about the strengthening of the shell of the cooling tower of Unit 5 of the Agios Dimitrios Power Plant in Kozani in Northern Greece, and the opening of a hole of 11.50m diameter. The strengthening of the tower was carried out with shotcrete, while the opening of the hole was done gradually with the gradual cutting of concrete segments weighing up to 2.5-3tn. The works were carried out at large heights from the ground (up to 35m) and were completed in 2 months in the summer of 2020.