THE ELECTRICITY SUPPLY SYSTEM ASPECT

Problems concerning all sector performance

Nuclear safety : Safety issue doubts

Although all producers and lobbyists follow the thought of the high level nuclear security and convince undecided part of societies, there are a group of serious objection about real face of nuclear reactor's safety.

In July 2009 NII - Nuclear Installations Inspectorate, organisation established to controlling and supervising the nuclear facilities addressed to AREVA (reactor's producer) and EDF (nuclear power plant operator in France) letter of concerns about EPR rector's safety solutions. Their notices was about following problems[70], [98]:

Control and instrumentation system is very complex and it does not ensure high level of safety despite of the fact that system is targeted to higher class solution.

  • No display systems
  • No manual control possibility, in case of accident operation dispatcher is not able to shut down the reactor. Any manual emergency shutdown is not provided from the power plant control room as well as remote shutdown.
  • Doubts that first French EPR can be built in the UK in 5 years, as design provides. According to NII, first EPR can not be constructed in less than 8 years. This point is particularly important because project financing is based on data about construction duration time.
  • There is no EPR in service now and the prototype is delayed, what has increased total cost of the investment.
  • As it appeared, Finnish regulatory office also raised concerns about EPR's control and instrumentation system.
  • In specific operating mode, when output power is increased from minimum to maximum in very rapidly, fuel rods can be launched. It can cause cracking of other rods and radioactive fission products penetration into coolant. Such outage can be described as a very serious. [99]

    • During generation II reactors development, safety concerns has been at lower levels that today. So old, operating reactors has a few defects that can not be removed. Although producers and lobbyists convince to high level of security but any serious accident caused by unpredictable conditions can lead to radioactive contamination of large area. Range of the contamination is said to be larger than in case of nuclear bomb detonation. Example of such unpredictable circumstances has taken place in Japan, where after earthquake of power over design assumption and tsunami wave, nuclear accident occurred. Accident was estimated by French regulatory to no. 6 in INES scale [100] just after tsunami. Japanese describe accident to no. 7. [101]

    New generation of reactors are said to highly secure. It is true because of passive safety systems. However, after precise analysis, they appear to have several serious problems (The U.K. Nuclear Installations Inspectorate concerns about EPR design [98] )

    Average reactors age is over 20 years. Reactors designed for 40 years of service are gained the extension of license for next 20 years. Age degradation of reactor's elements are not well known. Its detection is difficult and in consequence breakdowns due to degradation are difficult to predict.

    Reactors operation does not always run with designed aims. There are cases when, due to economic profits, nuclear power plants operates with reduced staff and what is worse, operators modify elementary service parameters like temperatures and pressures. It affects negatively the aging process and decreases security margin. [97]

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