By Mauro Orru

Enel SpA said Thursday that its subsidiaries Enel Chile SA and Enel Generacion Chile SA have agreed to accelerate the closure of the group's last coal-fired plant in Chile, possibly incurring an impairment of around 790 million euros ($867.7 million).

The Rome-based energy company said Enel Generacion Chile would request authorizations to cease operations at the Bocamina coal-fired power plant in Coronel at units Bocamina I and Bocamina II by Dec. 31, 2020 and May 31, 2022 respectively.

The first unit was previously scheduled to close by the end of 2023, with the second due to cease operations no later than 2040.

Enel said the possible impairment of around EUR790 million which could be reported in its half-year financial report, would correspond to the net book value of the two units as well as dismantling costs.

Write to Mauro Orru at mauro.orru@wsj.com; @MauroOrru94