Annual outages start at Olkiluoto 1 and Olkiluoto 2 plant units on Sunday

Annual outages start in Olkiluoto on 16 April when the Olkiluoto 1 plant unit (OL1) will 
be disconnected from electricity production for a refuelling outage which will take about 
one week. The maintenance outage to be carried out at Olkiluoto 2 (OL2) starts on 
Monday, 1 May. The duration of this outage is 16 days.

The refuelling and maintenance outages carried out at the plant units annually ensure that a 
good level of production and operability is maintained at the Olkiluoto nuclear power plant at 
all times. The outages are conducted at the OL1 and OL2 plant units in alternate years.  

The planned duration of the refuelling outage at OL1 is eight days. In addition to refuelling, 
various yearly repeated preventive maintenance activities, inspections, fault repairs and tests 
are to be executed at OL1. Electricity production is scheduled to restart at OL1 on 24 April.  

For OL2, the maintenance outage starts on May Day, 1 May and is estimated to take 16 days. 
Major activities during the maintenance outage include, e.g., the upgrading of the turbine 
automation system as well as the replacement of the electrical feedthrough modules in the 
containment.   

Refuelling is also always included in the maintenance outage, and thus carried out every year 
at both plant units.  The annual outage at OL2 is scheduled to be completed on Wednesday, 17 
May.  

In addition to TVO's own personnel, the annual outages will this year be carried out by some 
1,200 employees of subcontractors. About 200 experts in special fields from abroad take part 
in the outages.  

This year's theme of the annual outages is "Operational reliability safely". Everybody working 
in the annual outages is required to complete the online annual outage training already before 
entering the plant site. The execution of the annual outages to a high standard is important not 
only for safety, but also for the reliable production of the plants.   

The OL1 and OL2 plant units play an important part in base load production and 
implementation of the national energy and climate strategy in Finland. The plant units have 
been producing electricity for more than 40 years. Today, the electricity produced at the plant 
units accounts for about 16 percent of the Finnish electricity consumption and about 22 
percent of the electricity produced in Finland. 

Teollisuuden Voima Oyj has produced electricity for its shareholders, Finnish industrial and energy companies, safely and reliably for over 40 years. Nuclear electricity generated at TVO's Olkiluoto plant covers approximately 30 percent of Finland’s electricity demand once Olkiluoto 3’s regular electricity production has started. Climate-friendly nuclear electricity not only benefits society but also reduces the environmental impact of energy production. Moreover, the world's first final disposal facility for spent nuclear fuel is under construction in Olkiluoto.