In 2015, the Loviisa nuclear power plant generated a total of 8.47 terawatt hours (TWh) of power, accounting to about 13% of total power generation in the country.
The power plants features two nuclear reactors, each with a capacity of 510MW, and were commissioned in 1977.
The new ongoing investment program involves renewal of the power plant’s automation, upgrade of turbine generators and installation of the backup cooling system in order to extend the life. Loviisa Power Plant deputy director Thomas Buddas said: "The investment program currently being carried out at the Loviisa nuclear power plant is the most extensive in the plant’s history.
"The program aims to secure safe, reliable and profitable energy generation for the duration of the operating licenses, i.e. until 2027 and 2030."
The firm said that it invested approximately €80m last year and expects to continue significant investment in the coming years.
In order to improve plant safety, the firm invested in backup cooling system which is independent of seawater and the diesel fuel storage and distribution system.
Buddas said: "As a carbon dioxide-free production form, nuclear energy curbs climate change.
"The Loviisa power plant contributes with steady and reliable base-load electricity, which improves energy security of supply for society and supports the increase of renewable energy in the energy system."