With regard to the management of radioactive substances, TVO always strives to keep any emissions well below both the emission limits set by the authorities and TVO’s own target limits, which are more stringent than the official limits.
Radioactive emissions to the air
Emissions of noble gases into the atmosphere were 0.014% and emissions of iodine 0.48% of the permitted regulatory limit.
In 2016-2018, there were fuel leaks at the Olkiluoto power plant which resulted in the release of radioactivity into the environment through the main stack. The radiation safety of the environment was not endangered as a result of these events. Radiation doses and emissions remained under the regulatory limits with a good margin.
The theoretical radiation dose caused to neighboring residents is estimated to remain clearly below the threshold value. In 2017, the value was 0.38 µSv (threshold value: 100 µSv).
| Noble gas TBq (Kr-87 equivalent) | 0.91 | 3.43 | 9.69 | 0 | 0 |
% of allowed amount
| 0.01 | 0.04 | 0.1 | 0 | 0 |
| Iodine TBq (I-131 ekv) | 0.0005 | 0.0009 | 0.0016 | 0.00000008 | 0.00000025 |
| % sallitusta | 0.48 | 0.84 | 1.50 | 0 | 0.0002 |
| Aerosols TBq1) | 0.0006 | 0.025 | 0.24 | 0.000017 | 0.000007 |
| Tritium TBq | 1.32 | 1.07 | 2.65 | 1.04 | 0.69 |
| Carbon-14 TBq | 0.93 | 1.02 | 1.26 | 1.07 | 0.84 |
1) At the beginning of 2019, TVO observed that the
aerosol sampling efficiency of the vent stack's sampling system had not been
taken into account in the OL1 and OL2 emission reports during the operating
history of the plant units. Therefore, the reported aerosol emissions will be
revised later.
Carbon dioxide emission
TVO takes part in Finland’s battle against climate change by producing emission free base load power. The Olkiluoto nuclear power plant is included in the European Union emissions trading scheme that aims at monitoring greenhouse gas emissions and achieving the CO2 reduction goals. The power plant’s actual CO2 emissions are generated by the releases of the reserve boilers and the emergency diesel generators. The emergency diesel generators ensure the power supply of the plant in the possible but unlikely loss-of-power situation. In order to ensure safety, the emergency diesel generators are regularly tested in compliance with the technical specifications, which means that their emissions cannot be lowered. The replacement of the emergency diesel generators in OL1 and OL2 during the next few years will reduce particulate emissions to the air.
| CO2 emissions total (t) | 1,505 | 717 | 737 | 832 | 448 |
| OL1/OL2 back-up heating boilers (8 MW + 12 MW) | 1 | 22 | 95 | 496 | 1 |
| OL1/OL2 emergency diesels (8 x 1,8 MW) | 380 | 355 | 491 | 329 | 441 |
| OL3 emergency diesels (4 x 6,4 MW, 2 x 2,5 MW, 1 x 1,3 MW) | 1,124 | 340 | 152 | 7 | 6 |
