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Nuclear power and TVO in general

How large a share of the output of the power plant is released as heat into the sea?
About 2/3 of the thermal output of the reactor. The same applies to all condensing power plants, such as coal-fired power plants. The efficiency of the power plant is naturally being continuously improved. For example, TVO invested in 2010 and 2011 significantly, about 160 million euro, in upgrades designed to improve the efficiency and safety of the OL1 and OL2 plant units. Improved efficiency means that the share of the output of the plant units released as heat into the sea is smaller than before.

Why isn't the heat of the cooling water utilised as district heat?
Utilisation would not be lucrative, because Olkiluoto power plant is located far from major population centres and there are no other large clusters of electricity consumers nearby either. Olkiluoto nuclear power plant is designed for large-scale electricity generation, and the production of heat woul´d reduce the production of electricity.

Why is there a chimney on the roof of the plant units?
It is the exhaust vent stack of the power plant's ventilation system.

Can a nuclear power plant explode?
An actual explosion is not possible in a nuclear power plant, because the uranium-235 concentration of the reactor fuel is only 3-4%. A nuclear explosion requires a concentration of more than 90%. The explosions that took place in the Fukushima nuclear power plant accident in Japan as a result of the natural disaster in March 2011 were caused by the accumulation of hydrogen in the top parts of the reactor buildings. This kind of accumulation of hydrogen is prevented at the OL1 and OL2 plant units through technical arrangements. A nitrogen atmosphere prevails in the reactor containment during power operation to prevent hydrogen explosions. The containment is also equipped with permanent systems for controlled combustion of hydrogen released in a potential accident. The generation of hydrogen as a result of the overheating of the spent fuel stored in the pools of the reactor building, as well as possible hydrogen fires are prevented by securing the cooling of the fuel.

How has the possibility of terrorism been taken into account in the operation of the power plant?
Terrorism has been prepared for already in the construction of the power plant units, and in the plant upgrade projects and analyses carried out on the plant units. Safety is assured through both structural and administrative means. The systems responsible for safety are located on different sides of the plant unit, far away from each other. The simultaneous destruction of all of them is unlikely.
TVO also has in place a specific corporate security organisation. If necessary, this organisation works in cooperation with public organisations, such as the police, the coast guard, and the defence forces. Information related to security is classified.

Who is responsible for civil protection in the event of an accident?
The authorities defined in the Rescue Act, such as civil protection, fire and rescue authorities as well as the police are responsible for civil protection in the event of an accident. TVO is under the Nuclear Energy Act obliged to maintain an emergency organisation and to prepare for emergencies at the plant units. TVO is also legally obliged to provide information about the plant status in an emergency. Information to the general public is also provided by the Radiation and Nuclear Safety Authority and e.g. in the channels of the Finnish Broadcasting Company (Yleisradio). The Rescue Act was last amended on 1 July 2011. More specific procedures for nuclear power plant accidents and radiation emergencies were also defined in the amendment. Teollisuuden Voima Oyj organises regular exercises together with authorities to prepare for the highly improbable event of a nuclear power plant accident.

TVO's own emergency organisation follows the emergency plan. The purpose of the emergency plan is to prepare for the limitation of radiation accidents and consequences of such accidents potentially threatening the plant personnel, the environment and the plant itself.

Who is responsible in the event of an accident at the nuclear power plant?
Finnish nuclear power plants are legally obliged to take out nuclear liability insurance to cover damages caused to third parties. The primary responsibility always rests with the plant owner. The secondary responsible party is the State of Finland, and the third instance liable for damages is an association of Finland and other OECD Convention states.

What will happen if an aircraft should hit the power plant?
Owing to the massive construction of the nuclear power plant it is improbable that an aircraft crashing into the plant would cause significant damage. The heavy components of the aircraft would most likely only penetrate to the first rooms through the external wall. The systems responsible for plant safety are located on different sides of the plant unit, far away from each other. The simultaneous destruction of all of them is unlikely. The possibility of an aircraft crash has been taken into account already at the design stage of OL3 and the walls of the reactor building will be aircraft crash resistant.

Have accidents taken place at nuclear power plants?
Three severe accidents have taken place in nuclear power plants that produce electricity. The first accident occurred at the Three Mile Island plant in USA in 1979, the second in Chernobyl in Soviet Union in 1986 and the third in Fukushima, Japan, in 2011.

In the Three Mile Island accident, so much cooling water was lost through a safety valve, which stuck in open position that the reactor dried out, over-heated and melted in part. High levels of radioactivity were released inside the plant, but releases to the environment were minor.

The reactor of the Chernobyl nuclear power plant in Soviet Union (now Ukraine) was explosively destroyed in 1986. The complete collapse of the reactor resulted in a major release of radioactivity.

The most recent severe nuclear accident took place at the Fukushima Daichi plant in Japan. The root cause of the accident was an extremely exceptional natural disaster. A high-magnitude earthquake was followed by a tsunami wave, which hit the plant site located on the shore of the Pacific Ocean. The tsunami activated the mechanisms designed for controlled shutdown of the reactor, but due to the loss of off-site power and cooling water, they failed to operate as planned.

The INES scale (International Nuclear Event Scale) is used by the International Atomic Energy Agency (IAEA) for categorisation of nuclear power plant incidents and nuclear accidents to communicate the significance of the events in terms of radiation and nuclear safety.

There are seven INES levels. The level of an incident or accident is determined based on the deterioration of safety or radiation effects on the environment or the plant site. In addition to the seven non-zero levels, there is also level 0, which is applied to incidents with minor significance to radiation or nuclear safety.

The Fukushima and Chernobyl accidents are assigned to level seven and the Three Mile Island accident to level five.

Do you really inform the public openly of all disturbances?
TVO always openly communicates on its web site information both to the media and to the public about any significant disturbances that affect the operation and safety of the power plant. All abnormal events at the plant are reported to the Radiation and Nuclear Safety Authority (STUK), which is the authority that controls the safety of nuclear power plants in Finland. Both TVO and STUK publish an annual report about the most significant events, and STUK also posts every three months a summary of radiation safety on STUK's web site.

How close to a nuclear power plant are people allowed to live?
Regulations (YVL Guide 1.10 of the Radiation and Nuclear Safety Authority) prohibit permanent residence within ca. one kilometre from the nuclear power plant. The plant site is surrounded by a protective zone extending to a distance of about five kilometres from the facility. Dense settlement and hospitals or facilities inhabited or visited by a considerable number of people are not allowed within the zone. The number of permanent inhabitants should not be in excess of 200. Pursuant to a regulation of the Ministry of the Interior, an emergency planning zone extending to about 20 kilometres from the facility has been defined for the nuclear power plant. The zone shall be covered by detailed rescue plans for public protection drawn up by the authorities.

Why are visitors required to provide their identity?
The company is under regulatory obligation to know the identity of people within the nuclear power plant site.

Can anybody fish in Olkiluoto?
Fishing is allowed from a boat in the Olkiluoto water area, except for the entrances of the water intake and discharge channels, which are off-limits to fishers. An access permit is required within the power plant site.

Is the fence surrounding the plant units electrified?
Yes, because the fence serves as an alarm system.

How much electricity does the nuclear power plant need for its own operation?
One unit produces electricity at an output 880 MW. About 30 MW is needed for the operation of the plant itself.

Why are there more pressurised water reactors in the world than boiling water reactors? 
This is due to historical reasons, among others. The pressurised water reactor was more dominantly studied during the development of commercial plants at the initial stage of nuclear power in the 1960s and 1970s than the boiling water reactor. Pressurised water reactors were built in large series in e.g. France. The OL3 plant unit now under construction in Olkiluoto is a pressurised water reactor in type.

How much new nuclear power is under construction in other countries?
At present (February 2012), 64 reactors are under construction in the world. The climate issue and the concern about the supply reliability of energy have started to create new interest in nuclear power in many countries. The economic competitiveness of nuclear electricity has also improved the position of nuclear power in comparison with other alternatives.

According to the report published by the International Atomic Energy Agency IAEA in August 2011, 60 IAEA member countries have expressed interest in continued use of nuclear power and 24 countries are planning to expand their existing nuclear power programme.
At present about 30% of electricity is in the European Union produced with nuclear power. In addition to Finland, a new nuclear power plant unit is under construction in France. In Europe, nuclear power construction projects are being planned also in Slovakia, Bulgaria, Romania, Czech Republic, Hungary, Slovenia, Great Britain and Poland.

Our neighbouring country Sweden has modernised her existing plant units increasing their output and extending their lifespan. According to the new policy adopted in Sweden, construction licences are to be granted again for new plant units to replace the existing reactors. The new units would be built on the existing plant sites.

How has it been possible to increase the output of a plant unit?
Ever more efficient equipment and systems have become available through technological advances and with more operating experience gained on nuclear power. This has made significant increases in the turbine efficiency possible at the Olkiluoto plant units. New fuel technology has resulted in more energy being produced by the same amount of fuel.

Doesn't the increase in output endanger safety?
The increase in output has been planned on the basis of maintaining and improving the high safety level. New advance technology has increased the reliability of the plant, which translates into improved safety.

Can the output of the existing plant units be increased?
The upgrade projects implemented in 2010 and 2011 increased the net output of both plant units, OL1 and OL2, by ca. 20 MW. As the plant units are kept in pristine condition at all times, the possibility of further increases in output can be investigated also in the future, when improvements are implemented at the plant units in other respects.

How long can a power plant be in operation?
The current perception is that Olkiluoto power plant units 1 and 2 have a further 40 years of service life left. Commercial operation started at Olkiluoto 1 in 1979 and at Olkiluoto 2 in 1982.

How are the plant units going to be dismantled? Have plans for this been already prepared?
The radioactive components of the plant units will be dismantled and placed in the operating waste repository, which is located in Olkiluoto and will be expanded for the dismantling waste. The dismantling is planned to be carried out about 30 years after the units have been shut down. The plans consisting of the cost estimate, the schedule and the work plan have been prepared, and the funds required to cover the costs are being collected in the price of electricity.

What are the reasons for the different prices of nuclear electricity in different countries?
There are many reasons. Examples of factors affecting the costs of nuclear electricity include differences in engineering (e.g. an expensive cooling tower or the need for new infrastructure), how much electricity is produced annually, i.e. the capacity factor, differences related to fuel, spent fuel management and the funding procedure and possibly the commitment to expensive reprocessing.
Will the demand for electricity increase and will more electricity be needed in Finland in the future?
Different estimates of the demand for electricity are presented constantly. According to the estimates, the consumption of electricity will increase despite economic fluctuations. Pursuant to the Year 2008 Climate and Energy Strategy of the Finnish Government, the annual demand for electricity is expected to be ca. 103 terawatt-hours (TWh) in 2020, or if consumption can be reduced through energy efficiency measures, 98 TWh. The starting point of the strategy is to ensure that industrial investments are not restricted due to production capacity.

Finnish Energy Industries and the Confederation of Finnish Industries presented their common estimate of the demand for electricity in 2030. These organisations concluded that provided recovery from the current recession is rapid, the demand for electricity will be 111 TWh in 2030. Slow recovery would result in a consumption of 100 TWh. The rate of increase in the demand for electricity is highest in the service sector and transport. The demand for electricity increases by about 40% in the service sector, and hybrid and electric cars multiply the consumption of electricity in transport. The consumption of electricity for heating may decrease as a result of energy efficiency measures. The demand for electricity in the industry is estimated to increase by 2-16% in comparison with the pre-recession figures.

The energy police studies conducted in the EU in recent years, such as the energy Road Map 2050, indicate that the share of electricity of all energy production will increase despite the improvements made in energy efficiency. In Finland, 16.4% of the consumed electricity was imported electricity in 2011, i.e. the amount of imported electricity increased by more than 30 percent over 2010. Domestic electricity production capacity must be increased to reduce the amount of imported electricity. The growing consumption of electricity must also be covered with electricity produced in Finland.

Reasons for the growing consumption of electricity include e.g. population increase, higher gross national product as well as improved standard of living. The number of electrical appliances in households is still on the increase; heat pumps, for example, are used to replace oil heating. The degree of processing of industrial products also increases, and electricity plays a crucial role in their manufacture. The manufacture of all new products, such as bioproducts, increases the consumption of electricity. The growing demand for services also increases electricity demand.

Electricity must be produced with as low emissions as possible to curb climate change.

Does TVO participate in the uranium mining projects planned in Finland?
Uranium is mined in many countries by many companies. TVO is not involved in mining industry. TVO primarily acquires uranium from Kazakhstan, Australia and Canada. Uranium mining, like all mining activities, is governed by strict environmental regulations. TVO makes visits to the uranium mines to verify that the activities meet the defined objectives in terms of environmental protection and social responsibility.

How much will the construction of the new nuclear power plant cost to tax payers?
Nothing. No public funding is required for the construction of the nuclear power plant.

How would the construction of new nuclear power affect the use of renewable energy sources and promotion of energy efficiency?
Nuclear power and renewable energy sources do not compete on the same market. Nuclear power is used to produce baseload power for the needs of the society. Biomass is used in cogeneration of electricity and heat, while nuclear power has traditionally been used to produce just electricity. Since the previous decision on a new nuclear power plant was made, the use of bioenergy has increased by 2 percent per year. For example, Pohjolan Voima, which is the largest shareholder in TVO, has together with its cooperation partners invested more than 1.4 billion euro in biofuel-driven plants (1990–2008). This has generated in Finland more than 1100 MW of new electricity production capacity based on bioenergy. Wind power has also benefited from strong development in recent years with a specific programme launched to promote wind power. The companies that own TVO also participate in this programme.

The strategy also lays down ambitious objectives for energy savings. Practical measures are presented in the new energy saving programme. Most of the areas in which savings are to be made are related to heating.

When will OL3 finally be completed?
Based on the recent progress reports received from the plant supplier, AREVA-Siemens Consortium, TVO is preparing for the possibility that the start of the regular electricity production of Olkiluoto 3 nuclear power plant unit may be postponed until year 2016.

OL3 automation has attracted media attention. Will the automatic systems be reliable?
Like all solutions related to the operation of a nuclear power plant, automation will also be based on several mutually supporting and mutually independent systems. There will be both programmable and hardwired systems at Olkiluoto 3. This guarantees the safety of the plant in all conditions and situations.