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Experiences of Hungary's new NPP project
János Krutzler Hungarian Atomic Energy Authority
Department of Project Affairs
Content
• Hungary’s new NPP project
• Hungarian legal framework
• Recent update of the legal framework
• Recent and ongoing challenges
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Hungary’s new NPP project
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Hungary’s new NPP project so far • The idea of NPP extension has been on the agenda
since the 80’s (2*1000 MW additional capacity was planned for the site);
• 2008: energy policy conception: based on supply security and climate-protection objectives, the decision preparation work for new units started;
• 30th March, 2009: decision-in-principle of the Hungarian Parliament;
• January 2014: Intergovernmental agreement on the peaceful use of nuclear energy by Russia and Hungary:
Two VVER-1200 type reactors at the Paks site;
Russian loan for the 80% of construction costs;
• 7th December, 2014: Implementation agreements singed:
EPC contract;
Operation and maintenance support contract;
Agreement detailing fuel supply and the handling of spent fuel.
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28 March 2014
12 February 2014
14 January 2014
Intergovernmental Agreement (IGA)
About the cooperation on the peaceful use of nuclear energy
Act II/2014
About the announcement of the IGA, in force on 12 February
7 December 2014
Intergovernmental Agreement (Financial IGA)
About the interstate loan for the extension of Paks NPP
23 June 2014
Implementation agreements signed by Paks II Nuclear Power Plant
Development C-JSC and the Russian Joint-Stock Company
Nizhny Novgorod Engineering Company Atomenergoproekt
Act XXIV/2014
About the announcement of the FIGA
Paks NPP site
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Source: Paks 2 Environmental Impact Assessment Report
Operating units 4 x VVER-440
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Planned milestones of the licensing process:
2014: site assessment licence
2015: environmental licence
2015: licence in principle of the Hungarian Energy and Public Utility Regulatory Authority
2016: site permit
2017: construction licence
Planned milestones of the design and construction process:
2014: EPC contract
2015: general design and detailed design by the general contractor
2016: review of design
2018: start of construction
2025: start of commercial operation at Unit 1
2026: start of commercial operation at Unit 2
Environmental
licence
Site permit
Construction
licence
EPC
contract
general design by the general
contractor
Review of design
Detailed design
Site
assessment
licence
Licence of
MEKH
Start of construction
start of
commercial
operation at
Unit 1
2014 2017 2015 2016 2018 2021 2019 2020 2022 2025 2023 2024
Project schedule*
*Source: Dr. Attila Aszódi (Government Commissioner, Paks-2 project)
Hungarian legal framework
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Gov. Decree
No. 118/2011
Act No.
CXVI/1996 on
Atomic Energy
Nuclear Safety Code
Safety Guidelines
Internal procedures
Other regulations
1 2 3 … 10 9 …
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The Nuclear Safety
Regulation
in Hungary
NPPs Research and
Training Reactors
Spend Fuel Storage Facilities
Volume 1. – Nuclear safety authority procedures of nuclear facilities
Volume 2. – Management systems of nuclear facilities
Volume 3. Design require-
ments for operating NPPs
Volume 4. Operation of NPPs
Volume 5. Design and
Operation of Research and
Training Reactors
Volume 6. Design and
Operation of Spend Fuel
Storage Facilities
Volume 7. – Siting of Nuclear Facilities
Volume 8. – Decommissioning of Nuclear Facilities
Volume 10. – Terminology
Volume 9. – Construction of New Nuclear Facilities
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Structure of the Nuclear Safety
Code Volume 3A. Design
requirements for new NPPs
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Lifecycle stages of a NPP and the corresponding license
Recent update of the legal framework
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NPPs Research and
Training Reactors
Spend Fuel Storage Facilities
Volume 1. – Nuclear safety authority procedures of nuclear facilities
Volume 2. – Management systems of nuclear facilities
Volume 3. Design require-
ments for operating NPPs
Volume 4. Operation of NPPs
Volume 5. Design and
Operation of Research and
Training Reactors
Volume 6. Design and
Operation of Spend Fuel
Storage Facilities
Volume 7. – Siting of Nuclear Facilities
Volume 8. – Decommissioning of Nuclear Facilities
Volume 10. – Terminology
Volume 9. – Construction of New Nuclear Facilities
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Volume 3A. Design
requirements for new NPPs
Design requirements for NPPs (both for existing and new) where originally in a single NSC Volume. After careful consideration we concluded that it would be beneficial to separate requirements.
Recent review of the NSC
Existing vs. New NPPs (1/3)
Reasons for separating design requirements:
• it represented a significant challenge to create design requirements, that are fully applicable for exiting and new units at the same time without being either too strict or too permissive;
• the new units will have a design life of at least 60 years, so in order to meet future challenges we decided to create (in close cooperation with interested parties) requirements that are reasonably stricter than prevailing national and international requirements at that time (2013-2014);
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Existing vs. New NPPs (2/3)
Reasons for separating design requirements (cont.):
• the scope of design and analysis activities are different in chase of an exiting unit and a new unit (plant level initial design of new NPPs vs. modification of an existing plant/technology);
• design codes and standards have evolved (Gen II vs. Gen III+);
• some situations that are considered as “beyond design” for existing plants, are considered in the design of new plants (e.g. core melt);
• etc.
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Existing vs. New NPPs (3/3)
There was a need to differentiate design requirements for existing and new NPPs, so after convincing the PR and legal expert community, we created NSC 3. and 3a.
As a result of that, there are significant differences in (among others):
• Concept of Defense in-Depth (DiD);
• Probability based design basis event selection;
• Acceptance criteria;
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Example (1/4): DiD for existing NPP
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Level of DiD
Objective Associated plant condition
categories
1. Prevention of abnormal operation and
failures Normal operation
2. Control of abnormal operation and
detection of failures Anticipated operational
occurrences
3. Control of accident within the design basis DBA (single initiating event)
4.
Control of severe plant conditions, including prevention of accident progression and
mitigation of the consequences of severe accidents
Multiple failures
Severe accidents
5. Mitigation of radiological consequences of significant releases of radioactive material
-
Example (2/4): DiD for new NPP
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Level of DiD
Objective Associated plant condition
categories
1. Prevention of abnormal operation and
failures Normal operation (DBC1)
2. Control of abnormal operation and failures Anticipated operational
occurrences (DBC2)
3.
3.A Control of accident to limit radiological releases and prevent escalation to core melt
conditions
Postulated single initiating events (DBC3-4)
3.B Postulated multiple failure
events (DEC1)
4. Control of accidents with core melt to limit
offsite releases
Postulated core melt accidents (short and long
term) (DEC2)
5. Mitigation of radiological consequences of significant releases of radioactive material
-
Example (3/4): Determination of the design basis
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Plant type
Cut-off frequency values for design basis events
Internal initiating event due to the failure of a system, structure or component,
and/or human error [1/year]
Event resulting from external human activity
typical of the site [1/year]
Frequency of initiating events due to a recurring natural hazards [1/year]
New NPP 10e-6 10e-7 10e-5
Existing NPP 10e-5 10e-7 10e-4
Example (4/4): Acceptance criteria
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Plant type
Acceptance criteria
Loss of heat removal to the ultimate heat sink (primary
and alternative) [1/year]
CDF [1/year]
Collective frequency of
large and early releases [1/year]
New NPP <10e-7 <10e-5 <10e-6
Existing NPP - <10e-4 <10e-5
Practical example (molten core management)
Existing NPP (retrofitted) New NPP
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Source: http://www.world-nuclear-news.org/
Recent and ongoing challenges
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On the topic of this meeting...
For detailed information regarding experiences and practices in Hungary on the issues of interest please see the presented paper!
It includes:
• new concept of DiD, independence of DiD levels;
• requirements for practical elimination;
• requirements for DBA and DEC analysis;
• requirements on the use of non-permanent safety related equipment.
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Interpretation of DEC (new NPPs)
Operating condition
Description Frequency of event
(f [1/year])
DBC1 normal operation –
DBC2 anticipated operational occurrences f >10e-2
DBC2 low frequency design basis accidents 10e-2 > f >10e-4
DBC4 very low frequency design basis accidents 10e-4 > f >10e-6
DEC1 complex accidents without melting of the fuel in the core and the spent fuel pool
<10e-6 (indirect requirement)
DEC2 severe accidents resulting in a significant fuel melting
<10e-6 (indirect requirement)
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„3a.2.2.0400. It shall be demonstrated by probabilistic safety analyses for every design basis accidents that the multiplication product of the frequency of a given initiating event and the probability of failure of any safety function required for meeting the acceptance criteria for DBC4 operating conditions during a transient caused by the given initiating event does not exceed 10e-6/year.”
Determination of design extension
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Frequency of event [1/year]
10e-6 10e-7
DB „design extension” Practically eliminated, if <10e-7 @ „95/95”
Minimum list of events to be considered (requirement)
DEC selection by deterministic analyses supplemented by probabilistic methods and engineering judgement
DEC to be considered in the design
Acceptance criteria (e.g. LRF<10e-6)
Recent safety related challenges
• Multi unit PSA;
• Safety classification of SSCs;
• EPC contract vs. licensees ultimate responsibility;
• „Lessons not learned”;
• Effect of construction on the safe operation of existing units;
• Challenges for the regulatory body;
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Thank you for your attention!
Questions?
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