- •Radioactivity, nuclear fuel cycle, radioactive wastes management
- •Radioactivity
- •Activity
- •Ionizing radiation
- •Izotope:
- •Absorbed dose
- •Equivalent dose
- •Effective dose
- •Nuclear fuel cycle
- •Methodology of minimal price
- •Economic model of given system (project) – main rules for creation
- •Basic principles of economic effectiveness of projects – methodology of npv
- •Radioactive waste – three main related economic task
Radioactive waste – three main related economic task
How to finance decommissioning
How to finance radioactive waste (final) disposal (of different types)
How to finance temporary storage of spent fuel
RADIOACTIVE WASTE CLASSIFICATION
According to activity level
Low level waste (LLW)
Intermediate level waste (ILW)
High level waste – spent fuel
According to half time
Short lived isotopes
Intermediate lived isotopes
Long lived isotopes
According to origin
Industry, hospitals, research institutes, etc.
Nuclear power
Basically at least 10 half-times are needed
CZECH CASE EXAMPLE
(similar to other EU countries)
Responsibility of state – long time horizons
State authority responsible for waste record keeping (origin, amount, processing) and for waste disposal – SURAO in Czech republic
Waste originator should bear all current and future cost of waste management (uncertainty in future knowledge) – regulated fee
Decommissioning
Owners of nuclear plants should create provisions in money (bound account), periodically audited and approved by
System for LLW and ILW waste disposal – payment for one equivalent container (drum in drum system)
Institutional waste – three existing repositories (Richard, Bratrstvi, Dukovany)
Nuclear waste
System for spent fuel disposal – payment for 1 MWh produced
Deep geological repository – expected opening in 2065
NUCLEAR POWER PLANT – ACCIDENTS
Windscale – GB 8.10.1957, 5 points on scale
Grafite reactor, military purposes
Carelessness of reactor stuff – over heating of some fuel cells, ignition of surface from magnesium, fire took 4 days, 8% of fuel melted, app. 1.35 x1016 Bq released to the atmosphere
Area of 520 km2, drinking of mil prohibited, dose of public near plant – 5-60 mSv
Minimal attention of public (accident more important than in TMI)
Three Miles island, USA, 28.3.1979, 5 points on scale
PWR reactor, 1 year old, 880 MWe
Leakage of water from primary circuit, broken valve
Bad understanding of situation by staff, loss of cooling water, active zone started to melt
Threat of chemical explosion – water decomposed into oxygen and hydrogen
One week of stabilization, serious contamination of primary circuit, some leakages (under hygienic limits) to the environment
Jaslovské Bohunice, 22.2.1977, Slovak rep., 5 points on scale
Experimental reactor, 103 MWe, in operation from 1972
Natural uranium, moderated by heavy water, cooled by CO2,
Mistake of stuff when completing new fuel cell (continuous fuel exchange, each day some fuel cells is necessary to exchange)
Forgotten small bag with silicagel, cooling at this part of reactor blocked, warning signal switched off (false signal in past month), melting of fuel, operators tried to get back fuel cells, but impossible
Penetration of heavy water into primary circuit, fast erosion of fuel surface
Contamination of primary and part of secondary circuit
Černobyl nuclear power plant accident
Biggest acciedent
4 block of 1000 MWe in operation, 3. and 4. block put into operation in 1983
2 block under construction
RBMK reactor type – grafite reactor, boiling reactor, one circuit scheme, different organization of active zone, no pressurized vessel, 1693 channels
Continuous fuel exchange, higher plutonium content
Unstable on some conditions
Complex system fro zone stabilization
Accident
Experiment on 4 block – testing of new equipment in case of accident – power delivery
Causes of accident
Direct – combination mistakes and breach of rules
Indirect (system)
Psychological mistake of constructors
Pressure to fulfil planned activities