The ruling, which also bars Paolo Scaroni from holding public office for five years, puts a question mark on his chances of being reappointed head of Italy’s biggest listed company.
A court ruling in the north-eastern town of Rovigo said Scaroni had been sentenced, though no other details were provided, Reuters reported.
Sources cited by the news wire said the ruling was a result of violations of “environmental norms” at the Porto Tolle power plant in northern Italy during a period in which Scaroni was chief executive at Italy’s top utility, Enel.
Scaroni said he was shocked by the decision in a statement seen by Reuters.
“I am in no way involved in this matter and will appeal immediately,” he was quoted as saying.
“As shown by the defence, Enel’s Porto Tolle station has always met the existing standards including at the time of the facts contested,” he said.
The Italian court said that the current chief of utility Enel, Fulvio Conti, had been acquitted in the same case, Reuters reported.
Scaroni has already served three terms as chief at state-controlled Eni and his current mandate expires in May.
The Italian government wants state-controlled companies to eject from their boards any director charged of financial crimes, in a drive to fight corruption and improve corporate accountability.
The news comes amid a separate judicial inquiry into corruption allegations in Algeria concerning Eni and service unit Saipem.
Eni and Scaroni have fiercely denied involvement in that matter.