Performance of Operating, Adv. Light-Water Nuclear Reactor Designs (IAEA TECDOC-1245)

190 Pages·2001·5.587 MB·English

IAEA-TECDOC-1245

Performance of
perating and advanced
o
light water reactor designs

Proceedings of a Technical Committee meeting
held in Munich, Germany, 23–25 October 2000

October 2001
The originating Sections of this publication in the IAEA were:
Nuclear Power Technology Development Section, Nuclear Power Engineering Section
International Atomic Energy Agency
Wagramer Strasse 5
P.O. Box 100
A-1400 Vienna, Austria

PERFORMANCE OF OPERATING AND ADVANCED
LIGHT WATER REACTOR DESIGNS
IAEA, VIENNA, 2001
IAEA-TECDOC-1245
ISSN 1011–4289
© IAEA, 2001
Printed by the IAEA in Austria
October 2001
FOREWORD

Nuclear power can provide security of energy supply, stable energy costs, and can contribute
to greenhouse gas reduction. To fully realize these benefits, a continued and strong focus must
be maintained on means for assuring the economic competitiveness of nuclear power relative
to alternatives. The IAEA’s nuclear power programme includes information exchange
activities to achieve improved reliability and cost effectiveness of nuclear power plants by
promoting advanced engineering and technology.

Over the past several years, considerable improvements have been achieved in nuclear plant
performance. Worldwide, the average energy availability factor has increased from 66 per cent
in 1980 to 81 per cent in 1999, with some utilities achieving significantly higher values. This
is being achieved through integrated programmes including personnel training and quality
assurance, improvements in plant system and component design and plant operation, by
various means to reduce outage duration for maintenance and refuelling and other scheduled
shutdowns, and by reducing the number of forced outages.

Application of technical means for achieving high performance of nuclear power plants is an
important element for assuring their economic competitiveness. For the current plants, proper
management includes development and application of better technologies for inspection,
maintenance and repair. For future plants, the opportunity exists during the design phase to
incorporate design features and technologies for achieving high performance.

This IAEA Technical Committee meeting (TCM) was hosted by E.ON Energie, Munich,
Germany from 23–25 October 2000. The TCM provided a forum for information exchange on
design features and technologies incorporated into LWR plants commissioned within the last
15–20 years, and into evolutionary LWR designs still under development, for achieving
performance improvements with due regard to stringent safety requirements and objectives. It
also addressed on-going technology development expected to achieve further improvements
and/or significant cost reductions. The TCM was organized by the IAEA’s Division of
Nuclear Power. The IAEA officers responsible for this publication were J. Cleveland and T.
Mazour.
EDITORIAL NOTE
This publication has been prepared from the original material as submitted by the authors. The views
expressed do not necessarily reflect those of the IAEA, the governments of the nominating Member
States or the nominating organizations.
The use of particular designations of countries or territories does not imply any judgement by the
publisher, the IAEA, as to the legal status of such countries or territories, of their authorities and
institutions or of the delimitation of their boundaries.
The mention of names of specific companies or products (whether or not indicated as registered) does
not imply any intention to infringe proprietary rights, nor should it be construed as an endorsement
or recommendation on the part of the IAEA.
The authors are responsible for having obtained the necessary permission for the IAEA to reproduce,
translate or use material from sources already protected by copyrights.
CONTENTS
SUMMARY................................................................................................................................1

DESIGN FEATURES AND TECHNICAL MEANS FOR
IMPROVING PERFORMANCE, ECONOMICS AND SAFETY (Session I-a)

FP-4 and FP-5 Euratom research activities in the field of plant life management......................9
P. Lemaitre, G. Van Goethem
Design safety improvements of Kozloduy NPP to meet the
modern safety requirements towards the old generation PWR.................................................23
M.P. Hinovski, S. Sabinov
Upgrading Ukraine’s nuclear power plants...............................................................................31
O. Tkhorzhevskyy
The review of LWR operating experience in Ukraine..............................................................39
A. Afanasiev, A. Protopopov

DESIGN FEATURES AND TECHNICAL MEANS FOR
IMPROVING PERFORMANCE, ECONOMICS AND SAFETY (Session I-b)

Improvements of the nuclear power plant Isar 1.......................................................................51
D. Brosche
Safety analyses supporting the symptom oriented emergency operating procedures...............61
E. Toth
Means of achieving high load factors at Olkiluoto1 and 2.......................................................73
E. Patrakka
Implementation of the RCM approach at EDF NPPs: Current status.......................................81
A. Dubreuil-Chambardel, M. Martin-Onraet, C. Degrave
Maintenance management for nuclear power plant “integrated valve maintenance”...............89
P. Gerner, G. Zanner
Laguna Verde nuclear power plant: An experience to consider in advanced BWR design......99
L. Fuentes Márquez

DEVELOPMENT OF NEW DESIGNS AND TECHNOLOGIES WITH A
FOCUS ON PERFORMANCE AND ECONOMIC VIABILITY (Session II)

US Department of Energy Nuclear Energy Research Initiative..............................................109
F. Ross
Development activities on advanced LWR in Argentina........................................................113
S.E. Gómez
Development, operating experience and future plan of ABWR in Japan...............................121
N. Ujihara
Validation of thermal hydraulic computer codes for advanced light water reactor................131
J. Macek
Improvement of operational performance and increase of safety of
WWER-1000/V-392.........................................................................................................143
Y.A. Kurakov, Y.G. Dragunov, A.K. Podshibiakin,
N.S. Fil, V.N. Krushelnitsky, V.M. Berkovich
Design features in Korean next generation reactor focused on
performance and economic viability................................................................................155
J.S. Lee, M.S. Chung, J.H. Na, M.C. Kim, Y.S. Choi
EPR design: A combined approach on safety and economic competitiveness.......................167
R. Griedl, J. Sturm, C. Degrave, F. Kappler, M. Martin-Onraet

LIST OF PARTICIPANTS.....................................................................................................181
SUMMARY

The Technical Committee Meeting (TCM) on Performance of Operating and Advanced Light
Water Reactor Designs was convened within the framework of the IAEA’s International
Working Group on Advanced Technologies for Light Water Reactors. Topics addressed
within the frame of this International Working Group focus on technology developments for
improving economic competitiveness of LWRs while meeting safety objectives.

The TCM was attended by 32 participants from 14 Member States: Argentina (1), Bulgaria
(1), Czech Rep.(2), Finland (1), France (3), Germany (9), Hungary (2), Japan (1), Republic of
Korea (2), Mexico (1), Russian Federation (1), Slovakia (1), Spain (1), Ukraine (2)], the
European Commission (2) and the IAEA (2).

The meeting was chaired by D. Brosche, Director of E.ON Energie AG, and Manager of the
ISAR-1 and ISAR-2 Nuclear Power Plants.

A total of 19 technical papers were presented in the following areas:
(cid:1)(cid:2) Design features and technical means for improving current LWRs;
(cid:1)(cid:2) Development of new LWR designs and technologies with a focus on performance and
economic viability.

Key results concerning performance of current plants include the following:

The European Commission (EC) is funding an extensive project in plant life management at a
funding level of EURO 9.2 million within the 5th framework programme (1999–2002). This
work is being co-ordinated with the IAEA through EC participation in the IAEA’s
International Working Group on Plant Life Management. Technical areas addressed include
the following:
(cid:1)(cid:2) Integrity of equipment and structures
(cid:1)(cid:2) Irradiation embrittlement;
(cid:1)(cid:2) Optimization of operational conditions focusing on corrosion issues;
(cid:1)(cid:2) Prediction of structural safety margins;
(cid:1)(cid:2) Optimization of operational conditions focusing on dynamic fluid-structure
interactions;
(cid:1)(cid:2) On-line monitoring, inspection and maintenance;
(cid:1)(cid:2) Organization and management of safety.

Extensive modernization programmes have been carried out at older plants (e.g. ISAR-1 and
Olkiluoto-1 and -2) that have resulted in achieving both a high level of safety and competitive
economic performance. ISAR-1 has undergone extensive improvements since it was
connected to the grid in 1977. In 1999 ISAR-1 achieved the best performance record since
commissioning with an availability factor of 99.7% and a capacity factor of 98.7%. The
Olkiluoto units were commissioned in 1979 and 1982 respectively. Advanced features were
incorporated in the original design, and numerous improvements (e.g. exchange of power
conversion equipment to achieve power up-rating) have been made. The units have operated
with combined capacity factors of 90% and above since 1985. The units typically achieve
annual outage lengths of between 10 and 20 days.
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Many design improvements have been and are being carried out at Kozloduy Units 1,2,3 and 4
to meet modern safety requirements. The main areas include:
(cid:1)(cid:2) Primary circuit integrity;
(cid:1)(cid:2) Severe accident behavior;
(cid:1)(cid:2) Leak before break application;
(cid:1)(cid:2) Confinement leak tightness; and
(cid:1)(cid:2) Seismic design improvement.

Design improvements have been made in Ukrainian WWERs to meet safety requirements.
Examples of design changes involve the emergency core cooling system, and improvement of
the reactor control and protection system. Improved fuel management has resulted in
reductions of fuel cycle costs in the range of 10 per cent.

The Paks Nuclear Power Plant (NPP) experience with respect to development of symptom-
based emergency operating procedures (EOPs) was reported. These symptom based EOPs
improve the performance of the plant in the event of an incident or accident because they
provide a framework within which all critical safety functions can be monitored and
appropriate actions taken. They provide a complement to event-based procedures because it
isn’t possible to anticipate all plant events, particularly combinations of individual events. The
Paks NPP staff have integrated the existing event-based procedures with symptom-based
EOPs to provide a comprehensive framework to appropriately respond to all abnormal and
emergency conditions.

Optimized preventive maintenance programmes can contribute to ensuring both safe and
competitive NPPs. Reliability centered maintenance provides an optimization of preventive
maintenance. The principles underlying reliability centred maintenance include preventing
failures where the repercussions for the plant could be serious in terms of safety or economics.
The methodology involves evaluation of the functional consequences of failure, analyses of
experience feedback, and optimization of preventive maintenance tasks. Electricité de France
(EdF) has implemented preventive maintenance programmes based on a reliability centred
maintenance methodology at EdF nuclear plants, and results have shown benefits in safety,
performance and cost.

The nuclear plant service industry is implementing improved service approaches for
maintenance. An example is the integrated valve maintenance approach developed and offered
by Siemens. The goal is to optimize the overall sequence including advanced planning and
conduct of the maintenance activities. The approach has been carried out at several plants in
Europe.

Operational experience of current plants provides good guidance for developers of future
plants. As an example, experience of the Laguna Verde BWR in introducing flexibilities in
core flow operation at full power to achieve improved fuel utilitization provide useful
guidance in regard to design features and operating procedures to address turbulence and flow
induced vibrations. Power up-rating at this plant through the use of improved analytical
methods and calculational tools has been accomplished without decreasing any safety margin.
In summary, the papers presented concerning improvements in the performance and design
features of current plants reinforced the valuable contribution that operating experience
provides, both for current plants and in the design of new plants, particularly evolutionary
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plants. Operational experience has demonstrated that there is a potential to increase the
competitiveness of the existing nuclear power plants including relatively old ones. Further
improvement of nuclear power competitiveness is possible by the extension of NPP lifetimes.
This work is now being performed in some countries; for example, the possibility to increase
Novovoronezh-3&4 and then Kola-1&2 lifetime by 10–15 years is now being studied in
Russia. Another effective way to reduce the nuclear electricity cost is to increase the rated
power of the plant. ISAR-2 in Germany and the Olkiluoto and Loviisa plants in Finland
provide good examples of such activities.
Key results concerning new plant designs include the following:
Evolutionary designs for new plants have lower commercial risk than innovative designs
because they build directly on performance experience of existing plants. However, in some
countries, these designs are having difficulty in achieving competitiveness with alternative
electricity generating sources (e.g. combined cycle gas turbines). Innovative designs can
potentially be less expensive while also achieving very high safety levels. However, the
possible need to have a prototype as part of the development programme will be a large
financial impediment. Each generation of nuclear power plants has sought higher levels of
nuclear safety, with an associated cost. In the future, in order to remain competitive, it will be
necessary to first identify clear safety goals and then to find cost effective ways to achieve
these goals.
With regard to future plants, some evolutionary water-cooled reactors are starting operation or
are under construction, some designs have been certified by regulatory authorities, and some
are under development. Examples of evolutionary designs include the 1360 MW(e) Advanced
Boiling Water Reactor (ABWR) which is currently operating in Japan, the 1545 MW(e)
European Pressurized Water Reactor (EPR) which is under development by Nuclear Power
International, the boiling water reactor SWR-1000 of Siemens, the 1450 MW(e) Korean Next
Generation Reactor (KNGR) which is being developed by the Korea Electric Power
Corporation and the Korean nuclear industry on the basis of operating experience with the
Korean Standard Nuclear Plant (KSNP), the WWER-1000, V-392 design under development
in the Russian Federation, and the AP-600 which has been developed in the United States by
Westinghouse and certified by the US Nuclear Regulatory Commission.

The present situation encourages a strong focus on technologies for improving economics.
Evolutionary designs have incorporated the large experience base of operating plants plus
many technological developments to enhance safety — but these design features have often
had increased capital costs. Designers of evolutionary plants have of course had reductions of
both capital and operating costs as goals, but in some cases the target costs used in the design
activities have been considerably above costs that would be competitive in current privatized,
de-regulated markets. Further, design, development and certification of some evolutionary
designs has taken 12 years and more — maybe too long in changing market conditions.

Therefore, the nuclear industry is challenged to develop advanced reactors with
(cid:1)(cid:2) considerably lower capital costs and shorter construction times;
(cid:1)(cid:2) sizes (including small and medium sizes with load following capability) appropriate to
grid capacity and owner investment capability;
(cid:1)(cid:2) high levels of standardization and modularisation.
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Designers of innovative plants may be able to take even more advantage of cost reduction
approaches. Innovative designs are being developed in several countries for all reactor lines
(gas, water and liquid metal cooled). Goals include low capital cost, short construction time,
enhanced safety and proliferation resistant features. Several of the innovative designs are
small and medium size reactors (SMRs), which are a better fit to modest demand growth and
smaller electricity grids (e.g. in developing countries), are easier to finance, can be simpler
and often employ passive safety systems, and are a good fit for several non-electric
applications.

Innovative water-cooled reactors include integral designs, such as the CAREM design which
has been under development in Argentina since 1984, and high performance designs operating
thermodynamically in the supercritical regime (above 22 MPa and 374 C) to achieve high
thermal efficiency for reduced capital cost. In addition to the CAREM development activities,
development of integral designs is underway in the Republic of Korea for the SMART design,
in Russia for the VPBER-600 design, and in the USA. for the IRIS Generation IV design.
High performance designs operating in the supercritical regime are being examined co-
operatively by design and research organizations in Europe and Japan. Furthermore, Atomic
Energy of Canada, Ltd (AECL) has selected such systems as their innovative approach for
heavy water moderated reactors.

In the USA, the US Department of Energy initiated the Nuclear Energy Research Initiative
(NERI) in 1999 within its Office of Nuclear Energy, Science and Technology, as a result of
recommendations of President’s Committee of Advisors on Science and Technology
(PCAST) that the following should be addressed:
(cid:1)(cid:2) Technologies for proliferation resistant reactors and fuel cycles;
(cid:1)(cid:2) New designs with high efficiency, reduced cost and enhanced safety;
(cid:1)(cid:2) Designs with lower output; and
(cid:1)(cid:2) New technologies for
(cid:1)(cid:2) On-site and surface storage of waste; and
(cid:1)(cid:2) Permanent disposal of waste.

PCAST also suggested that the task areas should be recommended by scientific investigators
as a less prescriptive means of determining the tasks to be conducted. Awards are granted
following solicitation, merit review and a peer review and selection process. Collaboration is
encouraged among national laboratories, universities, industry and international R&D
organizations.

Funding for 1999 and 2000 for NERI was US$ 19 million and 24 million respectively, with an
increase anticipated for 2001. Forty-six projects were initiated in 1999 and ten more were
started in 2000. Some examples of ongoing activities within NERI that should contribute to
improved economics of future LWRs include:
(cid:1)(cid:2) A risk informed assessment of regulatory and design requirements;
(cid:1)(cid:2) A study of “smart” equipment and systems to improve reliability and safety;
(cid:1)(cid:2) A study of a larger version of the AP-600 design to benefit from economies-of-scale
while retaining passive system technology;
(cid:1)(cid:2) A study to develop means for forewarning of failure in critical equipment.
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