WorldWideScience

Sample records for power plant risk

  1. Development of nuclear power plant Risk Monitor

    International Nuclear Information System (INIS)

    Yang Xiaoming; Sun Jinlong; Ma Chao; Wang Lin; Gu Xiaohui; Bao Zhenli; Qu Yong; Zheng Hao

    2014-01-01

    Risk Monitor is a tool to monitor the real-time risk of a nuclear power plant for risk management and comprehensive decision-making, which has been widely used all over the world. The nuclear power plant Risk Monitor applies the real-time risk model with low-complicacy that could reflect the plant's actual configuration, automatically reads the plant's configuration information from the engineering system through the developed interface, and efficiently analyzes the plant's risk Dy the intelligent parallel-computing method in order to provide the risk basement for the safety management of nuclear power plant. This paper generally introduces the background, architecture, functions and key technical features of a nuclear power plant Risk Monitor, and validates the risk result, which could well reflect the plant's risk information and has a significant practical value. (authors)

  2. Risk analyses of nuclear power plants

    International Nuclear Information System (INIS)

    Jehee, J.N.T.; Seebregts, A.J.

    1991-02-01

    Probabilistic risk analyses of nuclear power plants are carried out by systematically analyzing the possible consequences of a broad spectrum of causes of accidents. The risk can be expressed in the probabilities for melt down, radioactive releases, or harmful effects for the environment. Following risk policies for chemical installations as expressed in the mandatory nature of External Safety Reports (EVRs) or, e.g., the publication ''How to deal with risks'', probabilistic risk analyses are required for nuclear power plants

  3. Nuclear power plant's safety and risk

    International Nuclear Information System (INIS)

    Franzen, L.F.

    1975-01-01

    Starting with a comprehensive safety strategy as evolved over the past years and the present legal provisions for the construction and operation of nuclear power plants, the risk of the intended operation, of accidents and unforeseen events is discussed. Owing to the excellent safety record of nuclear power plants, main emphasis in discussing accidents is given to the precautionary analysis within the framework of the licensing procedure. In this context, hypothetical accidents are mentioned only as having been utilized for general risk comparisons. The development of a comprehensive risk concept for a completely objective safety assessment of nuclear power plants remains as a final goal. (orig.) [de

  4. Hazard Identification, Risk Assessment and Risk Control (HIRARC Accidents at Power Plant

    Directory of Open Access Journals (Sweden)

    Ahmad Asmalia Che

    2016-01-01

    Full Text Available Power plant had a reputation of being one of the most hazardous workplace environments. Workers in the power plant face many safety risks due to the nature of the job. Although power plants are safer nowadays since the industry has urged the employer to improve their employees’ safety, the employees still stumble upon many hazards thus accidents at workplace. The aim of the present study is to investigate work related accidents at power plants based on HIRARC (Hazard Identification, Risk Assessment and Risk Control process. The data were collected at two coal-fired power plant located in Malaysia. The finding of the study identified hazards and assess risk relate to accidents occurred at the power plants. The finding of the study suggested the possible control measures and corrective actions to reduce or eliminate the risk that can be used by power plant in preventing accidents from occurred

  5. Risk monitor riskangel for risk-informed applications in nuclear power plants

    International Nuclear Information System (INIS)

    Wang, Fang; Wang, Jiaqun; Wang, Jin; Li, Yazhou; Hu, Liqin; Wu, Yican

    2016-01-01

    Highlights: • A general risk monitor riskangel with high-speed cutsets generator engine. • Benchmarks of actual nuclear power plant (NPP) instantaneous risk models. • Applications in daily operation, maintenance plan and component out of service. - Abstract: This paper studied the requirements of risk monitor software and its applications as a plant specific risk monitor, which supports risk-informed configuration risk management for the two CANDU 6 units at the Third Qinshan nuclear power plant (TQNPP) in China. It also describes the regulatory prospective on risk-informed Probabilistic Safety Assessment (PSA) applications and the use of risk monitor at operating nuclear power plants, high level technical and functional requirements for the development of CANDU specific risk monitor software, and future development trends.

  6. Nuclear power plant risk assembly and decomposition for risk management

    International Nuclear Information System (INIS)

    Iden, D.C.

    1985-01-01

    The state-of-the-art method for analyzing the risk from nuclear power plants is probabilistic risk assessment (PRA). The intermediate results of a PRA are first assembled to quantify the risk from operating a nuclear power plant in the form of (1) core damage (or core melt) frequency, (2) plant damage state frequencies, (3) release category frequencies, and (4) the frequency of exceeding specific levels of offsite consequences. Once the overall PRA results have been quantified, the next step is to decompose those results into the individual contributors to each of the four forms of risk in some rank order. The way in which the PRA model is set up to assemble and decompose the plant risk determines the ease and usefulness of the PRA model as a risk management tool for evaluating perturbations to the PRA model. These perturbations can take the form of technical specification changes, hardware modifications, procedural changes, etc. The matrix formalism developed by Dr. Stan Kaplan for risk assembly and decomposition represents a significant breakthrough in making the PRA model an effective risk management tool. The key to understanding the matrix formalism and making it a useful tool for managing nuclear power plant risk is the structure of the PRA model. PRA risk model structure and decomposition of the risk results are discussed with the Seabrook PRA as an example

  7. German risk study 'nuclear power plants, phase B'

    International Nuclear Information System (INIS)

    Heuser, F.W.

    1989-01-01

    The results of the German risk study 'Nuclear power plants, phase B' indicate that an accident in a nuclear power plant which cannot be managed by the safety systems according to design, is extremely improbable: Its probability is at about 3 to 100,000 per year and plant. Even if the safety systems fail, emergency measures can be effected in a nuclear power plant to prevent an accident. These in-plant emergency measures diminish the probability of a core meltdown to about 4 to 1,000,000 per year and plant. Hence, the accident risk is greatly reduced. The information given by the author are to smooth the emotional edge in the discussion about the safety of nuclear power plants. (orig.) [de

  8. Methods of assessing nuclear power plant risks

    International Nuclear Information System (INIS)

    Skvarka, P.; Kovacz, Z.

    1985-01-01

    The concept of safety evalution is based on safety criteria -standards or set qualitative values of parameters and indices used in designing nuclear power plants, incorporating demands on the quality of equipment and operation of the plant, its siting and technical means for achieving nuclear safety. The concepts are presented of basic and optimal risk values. Factors are summed up indispensable for the evaluation of the nuclear power plant risk and the present world trend of evaluation based on probability is discussed. (J.C.)

  9. Risks in the operation of hydroelectric power plants and nuclear power in Brazil

    International Nuclear Information System (INIS)

    Goldemberg, J.

    1986-01-01

    A comparison between the utilization of electrical energy generated by hydroelectric power plant and nuclear power plant is made. The risks from nuclear installations and the environmental effects of hydroelectric power plants and nuclear power plants are presented. (E.G.) [pt

  10. Risk perception among nuclear power plant personnel: A survey

    International Nuclear Information System (INIS)

    Kivimaeki, M.; Kalimo, R.

    1993-01-01

    This study investigated risk perception, well-being, and organizational commitment among nuclear power plant personnel. The study group, 428 employees from a nuclear power plant, completed a questionnaire which included the same questions as those in previous surveys on risk perception of lay persons and industrial workers. Hazards at work were not seen as a sizable problem by nuclear power plant personnel. The study group estimated the safety of nuclear power plants better and the possibility of a serious nuclear accident as more unlikely than the general public. Compared to employees in other industrial companies, the overall perceived risks at work among plant personnel did not exceed the respective perceptions of the reference groups. Risk-related attitudes did not explain well-being among plant personnel, but the relationship between the perceived probability of a serious nuclear accident at work and organizational commitment yielded to a significant correlation: Those plant workers who estimated the likelihood of an accident higher were less committed to the organization. 21 refs., 2 tabs

  11. [Risk communication in construction of new nuclear power plant].

    Science.gov (United States)

    He, Gui-Zhen; Lü, Yong-Long

    2013-03-01

    Accompanied by construction of new nuclear power plants in the coming decades in China, risk management has become increasingly politicized and contentious. Nuclear risk communication is a critical component in helping individuals prepare for, respond to, and recover from nuclear power emergencies. It was discussed that awareness of trust and public attitudes are important determinants in nuclear power risk communication and management. However, there is limited knowledge about how to best communicate with at-risk populations around nuclear power plant in China. To bridge this gap, this study presented the attitudinal data from a field survey in under-building Haiyang nuclear power plant, Shandong Province to measure public support for and opposition to the local construction of nuclear power plant. The paper discussed the structure of the communication process from a descriptive point of view, recognizing the importance of trust and understanding the information openness. The results showed that decision-making on nuclear power was dominated by a closed "iron nuclear triangle" of national governmental agencies, state-owned nuclear enterprises and scientific experts. Public participation and public access to information on nuclear constructions and assessments have been marginal and media was a key information source. As information on nuclear power and related risks is very restricted in China, Chinese citizens (51%) tend to choose the government as the most trustworthy source. More respondents took the negative attitudes toward nuclear power plant construction around home. It drew on studies about risk communication to develop some guidelines for successful risk communication. The conclusions have vast implications for how we approach risk management in the future. The findings should be of interest to state and local emergency managers, community-based organizations, public health researchers, and policy makers.

  12. Insurance risk of nuclear power plant concentrations

    International Nuclear Information System (INIS)

    Feldmann, J.

    1976-01-01

    The limited number of sites available in the Federal Republic of Germany for the erection of nuclear power plants has resulted in the construction of multiple nuclear generating units on a few sites, such as Biblis, Gundremmingen and Neckarwestheim. At a value invested of approximately DM 1,200/kW this corresponds to a property concentration on one site worth DM 2 - 3 billion and more. This raises the question whether a concentration of value of this magnitude does not already exceed the limits of bearable economic risks. The property risk of a nuclear power plant, as that of any other industrial plant, is a function of the property that can be destroyed in a maximum probable loss. Insurance companies subdivide plants into so-called complex areas in which fire damage or nuclear damage could spread. While in some foreign countries twin nuclear power plants are built, where the technical systems of both units are installed in one building without any physical separation, dual unit plants are built in the Federal Republic in which the complexes with a high concentration of valuable property are physically separate building units. As a result of this separation, property insurance companies have no grounds for assessing the risk and hence, the premium different from those of single unit plants. (orig.) [de

  13. Risk-benefit evaluation of nuclear power plant siting

    International Nuclear Information System (INIS)

    Miettinen, J.; Savolainen, I.; Silvennoinen, P.

    1976-01-01

    An assessment scheme is described for the risk-benefit analyses of nuclear power versus conventional alternatives. Given the siting parameters for the proposed nuclear plant an economic comparison is made with the most advantageous competitive conventional production scenario. The economic benefit is determined from the differential discounted annual energy procurement cost as a function of the real interest rate and amortization time. The risk analysis encompasses the following factors: radiation risks in normal operation, reactor accident hazards and economic risks, atmospheric pollutants from the conventional power plants, and fuel transportation. The hazards are first considered in terms of probabilistic dose distributions. In the second stage risk components are converted to a compatible form where excess mortality is used as the risk indicator. Practical calculations are performed for the power production alternatives of Helsinki where district heat would be extracted from the nuclear power plant. At the real interest rate of 10% and amortization time of 20 yr the 1000 MW(e) nuclear option is found to be Pound9.1 m per yr more economic than the optimal conventional scenario. Simultaneously the nuclear alternative is estimated to reduce excess mortality by 2 to 5 fatal injuries annually. (author)

  14. Power plants investment decision-making in consideration of investment risk

    International Nuclear Information System (INIS)

    Oda, Junichiro; Matsuhashi, Ryuji; Yoshida, Yoshikuni; Takashima, Ryuta

    2005-01-01

    In this paper, we consider the investment risk of nuclear power plants using the real options approach. It is essential that the Japanese society evaluate the investment risk, because nuclear power plants are facing definite uncertainty and Japanese governments intend to promote and assist nuclear power plants through subsidies and policy actions. We assumed that the wholesale market prices of electricity constitute the definite uncertainty and that the wholesale market prices follow the geometric Brownian motion with drift. Using the Bellman equation and a lattice framework, we evaluated the value of investment opportunity, the value of equipment, and the critical prices that are optimal prices to invest in a nuclear power plant in the finite time horizon. This analysis shows that higher volatility of the wholesale market prices would give power companies lower incentive to construct electric power plants, particularly capital-intensive power plants. In order to deliberate and hold the Japanese governments accountable for the economics of nuclear power plants, multifaceted evaluation is needed. (author)

  15. Cable fire risk of a nuclear power plant

    International Nuclear Information System (INIS)

    Aulamo, H.

    1998-02-01

    The aim of the study is to carry out a comprehensive review of cable fire risk issues of nuclear power plants (NPP) taking into account latest fire and risk assessment research results. A special emphasis is put on considering the fire risk analysis of cable rooms in the framework of TVO Olkiluoto NPP probabilistic safety assessment. The assumptions made in the analysis are assessed. The literature study section considers significant fire events at nuclear power plants, the most severe of which have nearly led to a reactor core damage (Browns Ferry, Greifswald, Armenia, Belojarsk, Narora). Cable fire research results are also examined

  16. Risk analysis for nuclear power plants

    International Nuclear Information System (INIS)

    Koelzer, W.

    1983-01-01

    The German risk analysis program for nuclear power plants aiming at the man and the environment is presented. An accident consequence model to calculate the radiological impact and the potential health effects is described. (E.G.) [pt

  17. Understanding the nature of nuclear power plant risk

    International Nuclear Information System (INIS)

    Denning, R. S.

    2012-01-01

    This paper describes the evolution of understanding of severe accident consequences from the non-mechanistic assumptions of WASH-740 to WASH-1400, NUREG-1150, SOARCA and today in the interpretation of the consequences of the accident at Fukushima. As opposed to the general perception, the radiological human health consequences to members of the Japanese public from the Fukushima accident will be small despite meltdowns at three reactors and loss of containment integrity. In contrast, the radiation-related societal impacts present a substantial additional economic burden on top of the monumental task of economic recovery from the nonnuclear aspects of the earthquake and tsunami damage. The Fukushima accident provides additional evidence that we have mis-characterized the risk of nuclear power plant accidents to ourselves and to the public. The human health risks are extremely small even to people living next door to a nuclear power plant. The principal risk associated with a nuclear power plant accident involves societal impacts: relocation of people, loss of land use, loss of contaminated products, decontamination costs and the need for replacement power. Although two of the three probabilistic safety goals of the NRC address societal risk, the associated quantitative health objectives in reality only address individual human health risk. This paper describes the types of analysis that would address compliance with the societal goals. (authors)

  18. Risk-based inspection in the context of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Wellington A.; Vasconcelos, Vanderley de; Rabello, Emerson G., E-mail: soaresw@cdtn.br, E-mail: vasconv@cdtn.br, E-mail: egr@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2015-07-01

    Nuclear power plant owners have to consider several aspects like safety, availability, costs and radiation exposure during operation of nuclear power plants. They also need to demonstrate to regulatory bodies that risk assessment and inspection planning processes are being implemented in effective and appropriate manner. Risk-Based Inspection (RBI) is a methodology that, unlike time-based inspection, involves a quantitative assessment of both failure probability and consequence associated with each safety-related item. A correctly implemented RBI program classifies individual equipment by its risks and prioritizes inspection efforts based on this classification. While in traditional deterministic approach, the inspection frequencies are constant, in the RBI approach the inspection interval for each item depends on the risk level. Regularly, inspection intervals from RBI result in risk levels lower or equal than deterministic inspection intervals. According to the literature, RBI solutions improve integrity and reduce costs through a more effective inspection. Risk-Informed In-service Inspection (RI-ISI) is the equivalent term used in the nuclear area. Its use in nuclear power plants around world is briefly reviewed in this paper. Identification of practice methodologies for performing risk-based analyses presented in this paper can help both Brazilian nuclear power plant operator and regulatory body in evaluating the RI-ISI technique feasibility as a tool for optimizing inspections within nuclear plants. (author)

  19. Risk-based inspection in the context of nuclear power plants

    International Nuclear Information System (INIS)

    Soares, Wellington A.; Vasconcelos, Vanderley de; Rabello, Emerson G.

    2015-01-01

    Nuclear power plant owners have to consider several aspects like safety, availability, costs and radiation exposure during operation of nuclear power plants. They also need to demonstrate to regulatory bodies that risk assessment and inspection planning processes are being implemented in effective and appropriate manner. Risk-Based Inspection (RBI) is a methodology that, unlike time-based inspection, involves a quantitative assessment of both failure probability and consequence associated with each safety-related item. A correctly implemented RBI program classifies individual equipment by its risks and prioritizes inspection efforts based on this classification. While in traditional deterministic approach, the inspection frequencies are constant, in the RBI approach the inspection interval for each item depends on the risk level. Regularly, inspection intervals from RBI result in risk levels lower or equal than deterministic inspection intervals. According to the literature, RBI solutions improve integrity and reduce costs through a more effective inspection. Risk-Informed In-service Inspection (RI-ISI) is the equivalent term used in the nuclear area. Its use in nuclear power plants around world is briefly reviewed in this paper. Identification of practice methodologies for performing risk-based analyses presented in this paper can help both Brazilian nuclear power plant operator and regulatory body in evaluating the RI-ISI technique feasibility as a tool for optimizing inspections within nuclear plants. (author)

  20. Flood risk analysis procedure for nuclear power plants

    International Nuclear Information System (INIS)

    Wagner, D.P.

    1982-01-01

    This paper describes a methodology and procedure for determining the impact of floods on nuclear power plant risk. The procedures are based on techniques of fault tree and event tree analysis and use the logic of these techniques to determine the effects of a flood on system failure probability and accident sequence occurrence frequency. The methodology can be applied independently or as an add-on analysis for an existing risk assessment. Each stage of the analysis yields useful results such as the critical flood level, failure flood level, and the flood's contribution to accident sequence occurrence frequency. The results of applications show the effects of floods on the risk from nuclear power plants analyzed in the Reactor Safety Study

  1. The German risk study for nuclear power plants

    International Nuclear Information System (INIS)

    Birkhofer, A.

    1980-01-01

    In August 1979 results of the ''German Risk Study for Nuclear Power Plants'' were published. The Main Report, in which approach and results of the study are documented, has been available since the end of 1979. It was the charter of the study - which was performed on behalf of the Minister of Research and Technology of the Federal Republic of Germany - to apply as far as possible the methods of the US Reactor Safety Study (WASH-1400) to German plant and site conditions. A direct transfer of the results was not deemed justified, mainly for the following reasons: There is quite a number of differences between the design of the reference plants of WASH-1400 (Surry-1, Peach Bottom-2) and German nuclear power plants. The mean population density in the Federal Republic of Germany is more than ten times of the United States. In the vicinity of nuclear power plants the ratio is about 3:1. To calculate the collective risk resulting from reactor accidents, a total of 25 plants at 19 different sites in the Federal Republic of Germany were considered. This included all plants with 600 MW or more electrical output, which were in operation, under construction or in licensing process by July 1, 1977. As an approximation to the real situation, it has been assumed that all 25 plants are technically identical to the reference plant

  2. Comparison of inhalation risks : oil- versus gas-fired urban power plants

    International Nuclear Information System (INIS)

    Levin, L.

    2000-01-01

    The risks due to inhalation of emitted trace substances from natural gas-fired power plants tend to be significantly lower than those from oil- or coal-fired plants. A 1994 study suggested that the median inhalation life-time cancer risk from gas-fired plants was about 4 in one billion. This is an acceptable risk range according to the United States Environmental Protection Agency (US EPA) classification of risks. In the same study, median oil plant risks were 8 in one billion. coal plant median risks ranged from 2 to 3 in one billion depending on the grade of coal being burned. The US EPA classifies risks from 1 to one million to one to 10,000 as being in an acceptable risk range. In some cases, gas plants were shown to exhibit higher inhalation risks than oil plants due to terrain, air circulation patterns, enhanced stack or building downwash or mechanical turbulence. Higher concentrations of very potent trace substances could also result in high inhalation risks. An examination of several power plants in an urban area showed that initial judgements about risk can often be incorrect

  3. Technical specifications review of nuclear power plants: a risk-informed evaluation

    International Nuclear Information System (INIS)

    Saldanha, Pedro Luiz da Cruz; Sousa, Anna Leticia; Frutuoso e Melo, Paulo Fernando Ferreira; Duarte, Juliana Pacheco

    2012-01-01

    The use of risk information by a regulatory body as part of an integrated decision making process addresses the way in which risk information is being used as part of an integrated process in making decisions about safety issues at nuclear plants – commonly referred to as risk-informed decision making. The risk-informed approach aims to integrate in a systematic manner quantitative and qualitative, deterministic and probabilistic safety considerations to obtain a balanced decision. Probabilistic Safety Assessment (PSA) is a methodology that can be applied to provide a structured analysis process to evaluate the frequency and consequences of accidents scenarios in nuclear power plants. Technical Specifications (TS) are specifications regarding the characteristics of nuclear power plants (variables, systems or components) of overriding importance to nuclear safety and radiation protection, which is an integral part of plant operation authorization. Limiting Conditions of Operation (LCO) are the minimum levels of performance or capacity or operating system components required for the safe operation of nuclear plants, as defined in technical specifications. The Maintenance Rule (MR) is a requirement established by the U. S. Nuclear Regulatory Commission (NRC) to check the effectiveness of maintenance carried out in nuclear plants, and plant configuration control. The control of plant configuration is necessary to verify the impact of the maintenance of a safety device out of service on plant safety. The Electric Power Research Institute (EPRI) has assessed the role of probabilistic safety analysis in the regulation of nuclear power plants with the following objectives: a) to provide utilities with an approach for developing and implementing nuclear power station risk-managed technical specification programs; and b) to complement and supplement existing successful configuration risk management applications such as MR. This paper focuses on the evaluation of EPRI

  4. Probability problems in seismic risk analysis and load combinations for nuclear power plants

    International Nuclear Information System (INIS)

    George, L.L.

    1983-01-01

    This workshop describes some probability problems in power plant reliability and maintenance analysis. The problems are seismic risk analysis, loss of load probability, load combinations, and load sharing. The seismic risk problem is to compute power plant reliability given an earthquake and the resulting risk. Component survival occurs if its peak random response to the earthquake does not exceed its strength. Power plant survival is a complicated Boolean function of component failures and survivals. The responses and strengths of components are dependent random processes, and the peak responses are maxima of random processes. The resulting risk is the expected cost of power plant failure

  5. Risks of potential accidents of nuclear power plants in Europe

    International Nuclear Information System (INIS)

    Slaper, H.; Eggink, G.J.; Blaauboer, R.O.

    1993-12-01

    This report is focussed on an integrated assessment of probabilistic cancer mortality risks due to possible accidental releases from the European nuclear power plants. For each of the European nuclear power plants the probability of accidental releases per year of operation is combined with the consequences in terms of the excess doses received over a lifetime (70 years). Risk estimates are restricted to cancer mortality and do not include immediate or short term deaths in the direct vicinity ( -8 per year in Western Europe. Going East the risks increase gradually to over 1000 x 10 -8 per year in regions of the former Soviet Union, where reactors of the Chernobyl type are located. The nuclear power plants in the East European countries dominate the estimated risk pattern and contribute at least 40-50% to the average risk in the West European countries. Improving the reactor safety in eastern European countries could lead to considerable reductions in estimated excess mortality risks. In western Europe the mortality risk might be reduced by a factor of two, and in eastern Europe by a factor of 100 to 1000. (orig.)

  6. Hierarchical structure for risk criteria applicable to nuclear power plants

    International Nuclear Information System (INIS)

    Hall, R.E.; Mitra, S.P.

    1985-01-01

    This paper discusses the development of a hierarchical structure for risk criteria applicable to nuclear power plants. The structure provides a unified framework to systematically analyze the implications of different types of criteria, each focusing on a particular aspect of nuclear power plant risks. The framework allows investigation of the specific coverage of a particular criterion and comparison of different criteria with regard to areas to which they apply. 5 refs., 2 figs

  7. Feasibility of risk-informed technology for japanese nuclear power plants

    International Nuclear Information System (INIS)

    Yoshida, Tomoo; Fujioka, Terutaka; Kirimoto, Yorihiro; Ueda, Nobuyuki; Kinoshita, Izumi; Kashima, Koichi

    2000-01-01

    Risk-informed technology utilizes Probabilistic Safety Assessment for streamlining the maintenance of nuclear power plants. With this technology, plant components are categorized as either high or low-safety-significant components. The Maintenance requirements focuses on high safety-significant components and are relieved for low safety significant ones. This is expected to reduce plant cost while maintaining safety. We investigated especially risk-informed inservice inspection of piping in U.S. nuclear power plants in the interest of determining its feasibility for Japanese plants. Quantitative and qualitative RI-ISI methods were developed by the ASME/Westinghouse Owners Group and EPRI, respectively. These methods have been incorporated in the ASME Section 11 Code Cases and endorsed by the U.S. Nuclear Regulatory Commission. The quantitative method evaluates component segment risks in terms of pipe failure probability calculated with a probabilistic fracture mechanics(PFM) model and pipe failure impact categorization on core damage frequency(CDF) calculated with PSA. The qualitative method uses pipe failure potential categorization derived from the plant service experiences and pipe failure impact on CDF derived from the PSA insight. The PFM model is applicable only to failures from initial welding defects and stress corrosion cracking, therefore it does not cover such significant failure mechanisms found in nuclear power plants as corrosion or high-cycle fatigue, etc.. Thus, a qualitative failure potential categorization method was developed on the basis of the service experiences of the U.S. nuclear power plants, so that appropriate categorization rules must be developed on the service experiences in Japanese plants. Accordingly, we have devised a software framework with a computer-aided system for the selection of risk significant elements. This system consists of a piping failure database module, a piping failure analysis module, and a piping failure potential

  8. Income risk of EU coal-fired power plants after Kyoto

    International Nuclear Information System (INIS)

    Abadie, Luis M.; Chamorro, Jose M.

    2009-01-01

    Coal-fired power plants enjoy a significant advantage relative to gas plants in terms of cheaper fuel cost. This advantage may erode (or turn into disadvantage) depending on CO 2 emission allowance price. Financial risks are further reinforced when the price of electricity is determined by natural gas-fired plants' marginal costs. We aim to empirically assess the risks in EU coal plants' margins up to the year 2020. Parameter values are derived from actual market data. Monte Carlo simulation allows compute the expected value and risk profile of coal plants' earnings. Future allowance prices may spell significant risks on utilities' balance sheets. (author)

  9. Nuclear power plant safety - the risk of accidents

    International Nuclear Information System (INIS)

    Higson, D.; Crancher, D.W.

    1975-08-01

    Although it is physically impossible for any nuclear plant to explode like an atom bomb, an accidental release of radioactive material into the environment is conceivable. Three factors reduce the probability of such releases, in dangerous quantities, to an extremely low level. Firstly, there are many safety features built into the plant including a leaktight containment building to prevent the escape of such material. Secondly, the quality of engineering and standards used are far more demanding than in conventional power engineering. Thirdly, strict government licensing and regulatory control is enforced at all phases from design through construction to operation. No member of the general public is known to have been injured or died as a result of any accident to a commercial nuclear power plant. Ten workers have died as a result of over-exposure to radiation from experimental reactors and laboratory work connected with the development of nuclear plant since 1945. Because of this excellent safety record the risk of serious accidents can only be estimated. On the basis of such estimates, the chance of an accident in a nuclear power reactor which could cause a detectable increase in the incidence of radiation-induced illnesses would be less than one chance in a million per year. In a typical highly industrialised society, such as the USA, the estimated risk of an individual being killed by such accidents, from one hundred operating reactors, is no greater than one chance in sixteen million per year. There are undoubtedly risks from reactor accidents but estimates of these risks show that they are considerably less than from other activities which are accepted by society. (author)

  10. How to deal with financial risk under the life circles of nuclear power plant

    International Nuclear Information System (INIS)

    Chen Shilong

    2010-01-01

    Nuclear power plants don't necessarily form enterprise boundary, in the background of nuclear power booming, what characteristics of financial risk exist in nuclear power plant, how to deal with such financial risk and how to sustain a stable development of nuclear power ? Based on the enterprise boundary theory of transaction fees, the separate of the nuclear power plant owner, engineering company and operating company comply with the cost-efficient principle. The financial risk of the plant owner come from the cash flow characteristics under different life circles of its nuclear power plants, due to the passivation of the asset structure in the construction and early operation periods, considering the effects of asset structure on financial risk is meaningless. Based on the owners with single reactor or constructing reactors, big-scale investment holding company is needed to conduct professional asset management, and to diversify the financial risk, on the other hand, professional engineering and operation companies can realize the scale and the multi-reactor advantages. (author)

  11. Regulatory Risk Management of Advanced Nuclear Power Plants

    International Nuclear Information System (INIS)

    George, Glenn R.

    2002-01-01

    Regulatory risk reflects both the likelihood of adverse outcomes during regulatory interactions and the severity of those outcomes. In the arena of advanced nuclear power plant licensing and construction, such adverse outcomes may include, for example, required design changes and construction delays. These, in turn, could significantly affect the economics of the plant and the generation portfolio in which it will operate. In this paper, the author addresses these issues through the lens of risk management. The paper considers various tools and techniques of regulatory risk management, including design diversity and hedging strategies. The effectiveness of alternate approaches is weighed and recommendations are made in several regulatory contexts. (author)

  12. A hierarchical structure for risk criteria applicable to nuclear power plants

    International Nuclear Information System (INIS)

    Hall, R.E.; Mitra, S.P.

    1982-01-01

    This paper discusses the development of a hierarchical structure for risk criteria applicable to nuclear power plants. The structure provides a unified framework to systematically analyze the implications of different types of criteria, each focusing on a particular aspect of nuclear power plant risks. The framework allows investigation of the specific coverage of a particular criterion and comparison of different criteria with regard to areas to which they apply

  13. Seismic fragilities for nuclear power plant risk studies

    International Nuclear Information System (INIS)

    Kennedy, R.P.; Ravindra, M.K.

    1983-01-01

    Seismic fragilities of critical structures and equipment are developed as families of conditional failure frequency curves plotted against peak ground acceleration. The procedure is based on available data combined with judicious extrapolation of design information on plant structures and equipment. Representative values of fragility parameters for typical modern nuclear power plants are provided. Based on the fragility evaluation for about a dozen nuclear power plants, it is proposed that unnecessary conservatism existing in current seismic design practice could be removed by properly accounting for inelastic energy absorption capabilities of structures. The paper discusses the key contributors to seismic risk and the significance of possible correlation between component failures and potential design and construction errors

  14. Cable fire risk of a nuclear power plant; Ydinvoimalaitoksen kaapelipaloriski

    Energy Technology Data Exchange (ETDEWEB)

    Aulamo, H.

    1998-02-01

    The aim of the study is to carry out a comprehensive review of cable fire risk issues of nuclear power plants (NPP) taking into account latest fire and risk assessment research results. A special emphasis is put on considering the fire risk analysis of cable rooms in the framework of TVO Olkiluoto NPP probabilistic safety assessment. The assumptions made in the analysis are assessed. The literature study section considers significant fire events at nuclear power plants, the most severe of which have nearly led to a reactor core damage (Browns Ferry, Greifswald, Armenia, Belojarsk, Narora). Cable fire research results are also examined. 62 refs.

  15. Risk perception of the public living in vicinity of nuclear power plant

    International Nuclear Information System (INIS)

    Li Xiaojuan; Hou Changsong; Wang Chunyan; Liu Ying; Sun Quanfu; Yu Ningle; Li Ningning; Zhou Rihui; Zhuang Jiayi

    2008-01-01

    Objective: To investigate the attitude toward and perception of the risk of nuclear power plant among the public residing in vicinity of nuclear power plant, as well as the related factors. Methods: A face-to-face interview on perceived radiation risks was conducted among 1408 individuals in Liangyungang City, Jiangsu Province, where the Tianwan nuclear power plant was under construction. The four groups was defined according to the distance between the residence of the subjects and the Tianwan nuclear power plant: <4 km, 4- 8 km, 8-30 km and 30-50 km. A was used to collect information on education, working history, religion, perception of major industries hazards especially nuclear power plant, and major factors may influence their perceptions. Ordinal logistic regression model was used to analyze the data. Results: About 91.18% of the interviewee heard about the nuclear power plant, 35.36% of them had knowledge about Chernobyl nuclear power plant accident, 71.05% of them believed that the nuclear power plant had no negative effects on environments, 37.03% of them believed that the nuclear energy was safe, 74.27% of them believed that it was necessary for China to develop nuclear energy, 63.29% of them supported the construction of the nuclear power plant in local area. Ordinal logistic regression analysis revealed that the higher education, higher family annual income, male, economic benefits from the nuclear power plant construction, and trust in local government having competency to handling emergencies were positive factors; otherwise, impression on nuclear power plant of bad influences on environment and health were negative factors. An inverted U-shaped with a right tailing relationship between negative attitudes toward nuclear power plant and distance to the plant was found. Conclusions: Education, gender, family annual income and expectation of economic benefit returns were the major factors influencing the perception of and attitudes toward nuclear power

  16. Health-safety and environmental risk assessment of power plants using multi criteria decision making method

    Directory of Open Access Journals (Sweden)

    Jozi Ali Seyed

    2011-01-01

    Full Text Available Growing importance of environmental issues at global and regional levels including pollution of water, air etc. as well as the outcomes such as global warming and climate change has led to being considered environmental aspects as effective factors for power generation. Study ahead, aims at examination of risks resulting from activities of Yazd Combined Cycle Power Plant located in Iran. Method applied in the research is analytical hierarchy process. After identification of factors causing risk, the analytical hierarchy structure of the power plant risks were designed and weight of the criteria and sub-criteria were calculated by intensity probability product using Eigenvector Method and EXPERT CHOICE Software as well. Results indicate that in technological, health-safety, biophysical and socio economic sections of the power plant, factors influenced by the power plant activities like fire and explosion, hearing loss, quantity of groundwater, power generation are among the most important factors causing risk in the power plant. The drop in underground water levels is the most important natural consequence influenced on Yazd Combined Cycle Power Plant.

  17. BARC-risk monitor- a tool for operational safety assessment in nuclear power plants

    International Nuclear Information System (INIS)

    Vinod, Gopika; Saraf, R.K.; Babar, A.K.; Hadap, Nikhil

    2000-12-01

    Probabilistic safety assessment has become a key tool as on today to identify and understand nuclear power plant vulnerabilities. As a result of the availability of these PSA studies, there is a desire to use them to enhance plant safety and to operate the nuclear stations in the most efficient manner. Risk monitor is a PC based tool, which computes the real time safety level and assists plant personnel to manage day-to-day activities. Risk monitor is a PC based user friendly software tool used for modification and re-analysis of a nuclear power plant. Operation of risk monitor is based on PSA methods for assisting in day to day applications. Risk monitoring programs can assess the risk profile and are used to optimise the operation of nuclear power plants with respect to a minimum risk level over the operating time. This report presents the background activities of risk monitor, its application areas and also gives the status of such tools in international scenarios. The software is based on the PSA model of Kaiga generating station and would be applicable to similar design configuration. (author)

  18. Risk management on nuclear power plant. Application of probabilistic risk assessment

    International Nuclear Information System (INIS)

    Kojima, Shigeo

    2003-01-01

    In U.S.A., nuclear safety regulation is moving to risk-informed regulation (RIR), so necessity of a standard to provide contents of probabilistic risk assessment (PRA) constructing its roots has been discussed for a long time. In 1998, the Committee on Nuclear Risk Management (CNRM) of the American Society of Mechanical Engineers (ASME) began to investigate the standard, of which last edition was published as the Standard for Probabilistic Risk Management for Nuclear Power Plant Applications: RA-S-2002 (PRMA) on April, 2002. As in the Committee, the Nuclear Regulatory Commission (NRC), electric power companies, national institutes, PRA specialists, and so on took parts to carry out many discussions with full energies of participants on risk management in U.S.A., the standard was finished after about four years' efforts. In U.S.A., risk management having already used PRA is successfully practiced, U.S.A. is at a stage with more advancing steps of the risk management than Japan is. Here was described on the standard of PRA and a concrete method of the risk management carried out at nuclear power stations. (G.K.)

  19. Public perception of risks from nuclear power plants in Japan, before the Great East Japan Earthquake

    International Nuclear Information System (INIS)

    Murayama, Rumiko; Nakaune, Naoko; Kishikawa, Hiroki; Uchiyama, Iwao

    2011-01-01

    On this research we aim to clarify public perception of risks from nuclear power plants before the Great East Japan Earthquake. The findings of the questionnaire survey conducted in 2010 showed that 1) about 70% of the people felt that they gained benefit from nuclear power plants and these were needed for their daily life. 2) Fifty percent respondents recognized there was danger to themselves and their family members with regards to nuclear power plants. The risks of nuclear power plants to Japanese society ware estimated higher than that risk to individuals of Japanese public. 3) Perception of risks from nuclear power plants to individual Japanese tended to be slightly lower between 1999 and 2010. (author)

  20. Maintenance risk management in Dayabay nuclear power plant

    International Nuclear Information System (INIS)

    He Xuhong; Tong Jiejuan

    2005-01-01

    The importance of proper maintenance to safe and reliable nuclear plant operation has long been recognized by the nuclear utility and regulatory body. This paper presents a process of maintenance risk management developed for a Chinese Nuclear Power Plant (NPP). The process includes three phases: (I) long term maintenance plan risk management, (II) monthly maintenance plan risk management, and (III) detailed risk management for high risk configuration. A risk matrix is developed for phase I whose purpose is to provide a rough guide for risk management in the making of the annual maintenance plan. For Phase II and Phase III, a software tool named Maintenance- Risk-Monitor is developed based on the internal initiating event, level 1 PSA model. The results of Phase II are the risk information of the all plant configurations caused by the unavailability of the components included the monthly maintenance plan. When the increase of core damage frequency (CDF) or the incremental core damage probability (ICDP) of a configuration is higher than the corresponding thresholds, Phase III is needed for this high risk configuration to get the useful information such as risk-importance components, human actions and initial events, from which appropriate preventive measurements could be derived. It is hoped that the provided process of maintenance risk management, together with the developed software tool, could facilitate the maintenance activities in the NPPs of China. (authors)

  1. Living near nuclear power plants and thyroid cancer risk: A systematic review and meta-analysis

    International Nuclear Information System (INIS)

    Kim, Jae Young; Bang, Ye Jin; Ee, Won Jin

    2016-01-01

    There has been public concern regarding the safety of residing near nuclear power plants, and the extent of risk for thyroid cancer among adults living near nuclear power plants has not been fully explored. In the present study, a systematic review and meta-analysis of epidemiologic studies was conducted to investigate the association between living near nuclear power plants and the risk of thyroid cancer. Our study does not support an association between living near nuclear power plants and risk of thyroid cancer but does support a need for well designed future studies given the conflicting results from sensitivity analysis.

  2. Living near nuclear power plants and thyroid cancer risk: A systematic review and meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Young [Dept. of Preventive Medicine, Keimyung University College of Medicine, Daegu (Korea, Republic of); Bang, Ye Jin; Ee, Won Jin [Dept. of Preventive Medicine, Korea University College of Medicine, Seoul (Korea, Republic of)

    2016-04-15

    There has been public concern regarding the safety of residing near nuclear power plants, and the extent of risk for thyroid cancer among adults living near nuclear power plants has not been fully explored. In the present study, a systematic review and meta-analysis of epidemiologic studies was conducted to investigate the association between living near nuclear power plants and the risk of thyroid cancer. Our study does not support an association between living near nuclear power plants and risk of thyroid cancer but does support a need for well designed future studies given the conflicting results from sensitivity analysis.

  3. Nuclear power plants without the risk of a reactor disaster

    International Nuclear Information System (INIS)

    Merz, L.

    1980-01-01

    Nowadays everybody believes that all nuclear power plants are an inevitable risk for the life of the people in its environment; this is a prejudice. This article points out that it is possible to plan nuclear power plants in a way that no deaths in the population have to be feared, even in the heaviest possible disturbances. In order to realise such nuclear power plants, it is necessary either to improve the cooling of the fuel rods by passive additional safety measures of which one unlimitedly efficient thus excluding a nuclear melting accident or to improve the safety containers so that it remains sufficiently tight. (orig./HP) [de

  4. Risk-oriented management of system configurations during power plant operation

    International Nuclear Information System (INIS)

    Kafka, P.

    1991-01-01

    The paper explains the purpose, design, and functions of an on-line database called risk monitor, which is developed on the basis of a risk model mapping an entire plant and the functions of the system configurations by a probabilistic and risk-oriented approach in a computerized simulation model. The frequency of occurrence of the various failure modes is computed and specified by fault tree analysis and event tree analysis. The monitoring system is a diagnostic tool for power plant operators. (DG) [de

  5. Risk management methodology applied at thermal power plant

    International Nuclear Information System (INIS)

    Coppolino, R.

    2007-01-01

    Nowadays, the responsibility of the environmental risks, connected the productive processes and to the products of an enterprise, represent one of the main aspects which an adequate management approach has to foresee. In this paper it has been evaluated the guidelines followed by Edipower Thermoelectric Power plant of S. Filippo di Mela (ME). These guidelines were given in order to manage the chemical risk connected to the usage of various chemicals with which the workers get in touch when identifying the risks of the methodology introduced by the AZ/NZS 4360:2004 Risk Management Standard

  6. Development of full power risk monitoring system for UCN 3 and 4 nuclear power plants

    International Nuclear Information System (INIS)

    Kim, Seung Hwan; Jang, Seung Chul; Kim, Kil Yoo; Han, Sang Hoon; Jung, Won Dae

    2002-03-01

    This report describes full power risk monitoring system (DynaRM) of NPPs which evaluates the current plant risk and monitor the risk change caused by the configuration change due to preventive maintenance or periodic maintenance activities. In order to calculate the core damage frequency, the inoperable equipment's basic event should be submitted to a quantification engine. DynaRM uses a risk monitor model converted from PSA model as the quantification engine, which can respond fast for the various equipment configuration changes. DynaRM is developed to solve these kinds of problems and difficulties. The main two key features of DynaRM are real time risk monitoring and real time maintenance plan decision supporting. With DynaRM, the plant risk can be calculated automatically only with out of service equipment information and equipment maintenance scheduling is easy by modifying the detail schedule plan. We have developed the DynaRM for the Korean standard nuclear power plant and it is currently using at Ulchin 3,4 NPP. The adaptation for the other NPPs is also easy with a little modification since DynaRM was developed by considering it to be used in the other NPPs. Moreover, we also expect DynaRM will be a good advisory tool for the plant risk monitoring and maintenance scheduling

  7. Toward risk-based control of nuclear power plant configurations

    International Nuclear Information System (INIS)

    Samanta, P.K.; Veseley, W.E.; Kim, I.S.

    1992-01-01

    This paper presents an evaluation of the configuration risks associated with the operation of a nuclear power plant and the approaches to control these risks using risk-based configuration control considerations. In that context, the actual and maximum potential configuration risks at a plant are analyzed and the alternative types criteria for a risk-based configuration control systems are described. The risk-based configuration calculations which are studied here focus on the core-melt frequency impacts from given plant configurations, the configurations which cause large core-melt frequency increases can be identified and controlled. The duration time in which the configuration can exist can then be limited or the core-melt frequency level associated with the configuration can be reduced by various actions. Futhermore, maintenances and tests can be scheduled to avoid the configurations which cause large core-melt frequency increases. Present technical specifications do not control many of these configurations which can cause large core-melt frequency increases but instead focus on many risk-unimportant allowed outage times. Hence, risk-based configuration management can be effectively used to reduce core-melt frequency associated risks at a plant and at the same time can provide flexibility in plant operation. The alternative strategies for controlling the core-melt frequency and other risk contributions include: (1) controlling the increased risk level which is associated with the configuration; (2) controlling the individual configuration risk which is associated with a given duration of a configuration; (3) controlling the time period configuration risk from configurations which occur in a time period. (orig.)

  8. Efforts to utilize risk assessment at nuclear power plants

    International Nuclear Information System (INIS)

    Narumiya, Yoshiyuki

    2015-01-01

    Risk assessment means the use of the outputs that have been obtained through risk identification and risk analysis (risk information), followed by the determination of the response policy by comparing these outputs with the risk of judgement standards. This paper discusses the use of risk information with multifaceted nature and its significance, and the challenges to the further penetration of these items. As the lessons and risk assessment learnt from the past accidents, this paper takes up the cases of the severe accidents of Three Mile Island, Chernobyl, and Fukushima Daiichi power stations, and discusses their causes and expansion factors. In particular, at Fukushima Daiichi Nuclear Power Station, important lessons were shortage in measures against the superimposition of earthquake and tsunami, and the insufficient use of risk assessment. This paper classified risk assessment from the viewpoint of risk information, and showed the contents and index for each item of risk reduction trends, risk increase trends, and measures according to the importance of risk. As the benefits of activities due to risk assessment, this paper referred to the application cases of the probabilistic risk assessment (PRA) of IAEA, and summarized the application activities of 10 items of risk indexes by classifying them to safety benefits and operational benefits. For example, in the item of flexible Allowed Outage Time (AOT), the avoidance of plant shutdown and the flexibility improvement of maintenance scheduling at a plant are corresponding to the above-mentioned benefits, respectively. (A.O.)

  9. Modern Risk Assessment for Nuclear Power Plants High-Voltage Substations

    International Nuclear Information System (INIS)

    Ioan, S.; Hurdubetiu, S.; Marza, F.; Mocanu, M.; Stefan, M.

    2002-01-01

    The paper describes a first Romanian attempt to set up the methodology for risk assessment and control within high-voltage substations, developed for the Nuclear power plant in Cernavoda (Romania). Considering the present risk assessment methods the MENER Project will develop a new methodology, in line with the European Community legislation and with the specific regional needs. In order to correctly shape the necessary resources required by a risk analysis a large size enterprise (a nuclear power plant) is selected and the following five indicators will be estimated: the economic profit, environmental risk, indirect (future) risk, technology improvement and physic and psychological risk. The results are expected to considerably facilitate risk assessment, by: evaluating project acceptability; evaluating equipment compliance to regulatory criteria; estimating excluding clearances; easing the design of emergency programmes; identifying the equipment use restrictions; identifying the risk sources; selecting the maintenance and risk reduction methods; testing the procedures leading to future regulatory norms; suitability of the risk management system modification. The immediate result of employing modern risk assessment methods could be the decrease by one third of the expenses required by environment protection, staff health and labor safety and quality management. (author)

  10. Risk management: A tool for improving nuclear power plant performance

    International Nuclear Information System (INIS)

    2001-04-01

    This technical document on risk management as a tool for improving nuclear power plant (NPP) operations is part of an ongoing project on management of NPP operations in a competitive environment. The overall objective of this project is to assist the management of operating organizations and NPPs in identifying and implementing appropriate measures to remain competitive in a rapidly changing business environment. Other reports developed through this project have identified overall strategies and techniques that NPP operating organization managers can use to succeed in more competitive energy markets. For example, in IAEA-TECDOC-1123, Strategies for Competitive Nuclear Power Plants, one of the most important strategies identified was integrated risk management. This publication provides a recommended structure for risk management along with examples of how NPP operating organizations are using this tool to help them integrate safety, operational and economic related risks in a changing business environment

  11. Living near nuclear power plants and thyroid cancer risk: A systematic review and meta-analysis.

    Science.gov (United States)

    Kim, Jaeyoung; Bang, Yejin; Lee, Won Jin

    2016-02-01

    There has been public concern regarding the safety of residing near nuclear power plants, and the extent of risk for thyroid cancer among adults living near nuclear power plants has not been fully explored. In the present study, a systematic review and meta-analysis of epidemiologic studies was conducted to investigate the association between living near nuclear power plants and the risk of thyroid cancer. A comprehensive literature search was performed on studies published up to March 2015 on the association between nuclear power plants and thyroid cancer risk. The summary standardized incidence ratio (SIR), standardized mortality ratio (SMR), and 95% confidence intervals (CIs) were calculated using a random-effect model of meta-analysis. Sensitivity analyses were performed by study quality. Thirteen studies were included in the meta-analysis, covering 36 nuclear power stations in 10 countries. Overall, summary estimates showed no significant increased thyroid cancer incidence or mortality among residents living near nuclear power plants (summary SIR=0.98; 95% CI 0.87-1.11, summary SMR=0.80; 95% CI 0.62-1.04). The pooled estimates did not reveal different patterns of risk by gender, exposure definition, or reference population. However, sensitivity analysis by exposure definition showed that living less than 20 km from nuclear power plants was associated with a significant increase in the risk of thyroid cancer in well-designed studies (summary OR=1.75; 95% CI 1.17-2.64). Our study does not support an association between living near nuclear power plants and risk of thyroid cancer but does support a need for well-designed future studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Construction risks of nuclear power plants for use in cost-effectiveness considerations

    International Nuclear Information System (INIS)

    Bock-Werthmann, W.

    1986-08-01

    The construction risk study is concerned with a nuclear power station of 1300 MW(e) design output. The risk figures obtained demonstrate that construction risks of nuclear power plants form a substantial share of the total risk from all steps of the nuclear fuel cycle. When compared with other risk figures it is apparent that only the fatalities caused by the extraction of uranium are of similar magnitude. (55 references). (DG)

  13. Risk management in Taiwan's nuclear power plants by adopting TIRM-2

    International Nuclear Information System (INIS)

    Chao, Chun-Chang; Kao, Tsu-Mu; Huang, Shian-Hung

    2003-01-01

    The TIRM-2 is the second generation risk monitor developed by INER and TPC. By providing risk indexes such as CDF, LERF, ΔCDF, ΔLERF, importance measurements and availability of safety systems, the TIRM-2 can precisely capture the plant risks and can serve as a better management resource. Examples about how to use TIRM-2 for the risk management are discussed in this paper. For plant at power operation, the TIRM-2 allows the plant staff to change plant configuration directly from the P and I Diagram. For a new plant configuration, only a few minutes will be spent for TIRM-2 to recalculate all the risk indexes. TIRM-2 can also provide risk profile and the associated risk indexes based on a given online maintenance schedule. The risk profile of CDF and LERF with ΔCDF and ΔLERF will help the plant staff with preparing associated information for the applications of risk-informed, performance-based regulation. With the proposed refueling outage schedule, the TIRM-2 can predict status of safety system and risk profile of CDF hourly. All calculations can be done within 40 minutes for a typical 50-days outage schedule. The plant staff and managers can rearrange the maintenance schedule referring to TIRM-2' predicted results and avoiding the plant entering into a potential high-risk situation. With the capability of performing both CDF and LERF calculations, the TIRM-2's will become a very helpful tool in monitoring the risk of different plant status and will provide further information directly for risk-informed applications. (author)

  14. Probabilistic risk assessment in nuclear power plant regulation

    Energy Technology Data Exchange (ETDEWEB)

    Wall, J B

    1980-09-01

    A specific program is recommended to utilize more effectively probabilistic risk assessment in nuclear power plant regulation. It is based upon the engineering insights from the Reactor Safety Study (WASH-1400) and some follow-on risk assessment research by USNRC. The Three Mile Island accident is briefly discussed from a risk viewpoint to illustrate a weakness in current practice. The development of a probabilistic safety goal is recommended with some suggestions on underlying principles. Some ongoing work on risk perception and the draft probabilistic safety goal being reviewed on Canada is described. Some suggestions are offered on further risk assessment research. Finally, some recent U.S. Nuclear Regulatory Commission actions are described.

  15. Methodology for risk-based configuration control of nuclear power plant operation

    International Nuclear Information System (INIS)

    Valle, Antonio Torres; Oliva, Jose de Jesus Rivero

    2012-01-01

    The hazardous configurations control in Nuclear Power Plants is an application of a previous Probabilistic Safety Analysis (PSA). A more complete option would be the risk monitoring for the online detection of these configurations but expert personnel would be required to deal with the complexities of PSA and risk monitor. The paper presents a simpler but effective approach: a method of configuration control, based on dependencies matrixes. The algorithm is included in a computer code called SECURE A-Z. The configuration control is carried out in a qualitative way, without previous PSA results and not using a Risk Monitor. The simplicity of the method warrants its application to facilities where these tools have not been developed, allowing the detection of hazardous configurations during operation and increasing plant safety. This configuration control system was implemented in the Embalse Nuclear Power Plant in Argentina. The paper shows the application of the algorithm to the analysis of a simplified safety system. (author)

  16. Cost-effectiveness analysis of risk reduction at nuclear power plants

    International Nuclear Information System (INIS)

    Lochard, J.; Maccia, C.; Pages, P.

    1985-01-01

    Cost-effectiveness analysis of risk reduction is now widely accepted as a rational analytical framework to consistently address the resource allocation problem underlying any risk management process. This paper presents how this technique can be usefully applied to complex systems such as the management of radioactive releases from nuclear power plants into the environment. (orig.) [de

  17. Applicability of PRA methods and data to the financial risk assessment of nuclear power plants

    International Nuclear Information System (INIS)

    El-Sheik, K.A.

    1985-01-01

    Financial risk assessment, where the probability and severity of financial consequences are estimated, offers a logical framework for organizing and evaluating data pertinent to nuclear power plant accidents. Under the sponsorship of the Electric Power Research Institute, General Electric investigated the feasibility of financial risk assessment of nuclear power plants and of applying PRA methods and data in such an assessment. This paper summarizes the main findings of this investigation. Specifically, the paper discussed the following topics: definition of financial consequences and financial risk; overall approach for financial risk assessment and how it compares with the approach for PRA used in the Reactor Safety Study; and specific financial risk assessment procedures for defining initiating events, plant response sequences, institutional scenarios, and financial consequences and how they compare to analogous procedures for PRA

  18. Development of a dynamical systems model of plant programmatic performance on nuclear power plant safety risk

    International Nuclear Information System (INIS)

    Hess, Stephen M.; Albano, Alfonso M.; Gaertner, John P.

    2005-01-01

    Application of probabilistic risk assessment (PRA) techniques to model nuclear power plant accident sequences has provided a significant contribution to understanding the potential initiating events, equipment failures and operator errors that can lead to core damage accidents. Application of the lessons learned from these analyses has resulted in significant improvements in plant operation and safety. However, this approach has not been nearly as successful in addressing the impact of plant processes and management effectiveness on the risks of plant operation. The research described in this paper presents an alternative approach to addressing this issue. In this paper we propose a dynamical systems model that describes the interaction of important plant processes on nuclear safety risk. We discuss development of the mathematical model including the identification and interpretation of significant inter-process interactions. Next, we review the techniques applicable to analysis of nonlinear dynamical systems that are utilized in the characterization of the model. This is followed by a preliminary analysis of the model that demonstrates that its dynamical evolution displays features that have been observed at commercially operating plants. From this analysis, several significant insights are presented with respect to the effective control of nuclear safety risk. As an important example, analysis of the model dynamics indicates that significant benefits in effectively managing risk are obtained by integrating the plant operation and work management processes such that decisions are made utilizing a multidisciplinary and collaborative approach. We note that although the model was developed specifically to be applicable to nuclear power plants, many of the insights and conclusions obtained are likely applicable to other process industries

  19. Research on the Application of Risk-based Inspection for the Boiler System in Power Plant

    Science.gov (United States)

    Li, Henan

    2017-12-01

    Power plant boiler is one of the three main equipment of coal-fired power plants, is very tall to the requirement of the safe and stable operation, in a significant role in the whole system of thermal power generation, a risk-based inspection is a kind of pursuit of security and economy of unified system management idea and method, can effectively evaluate equipment risk and reduce the operational cost.

  20. Prediction of Maintenance Period of Equipment Through Risk Assessment of Thermal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Song, Gee Wook; Kim, Bum Shin; Choi, Woo Song; Park, Myung Soo [KEPCO Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    Risk-based inspection (RBI) is a well-known method that is used to optimize inspection activities based on risk analysis in order to identify the high-risk components of major facilities such as power plants. RBI, when implemented and maintained properly, improves plant reliability and safety while reducing unplanned outages and repair costs. Risk is given by the product of the probability of failure (Pof) and the consequence of failure (COF). A semi-quantitative method is generally used for risk assessment. Semi-quantitative risk assessment complements the low accuracy of qualitative risk assessment and the high expense and long calculation time of quantitative risk assessment. The first step of RB I is to identify important failure modes and causes in the equipment. Once these are defined, the Pof and COF can be assessed for each failure. During Pof and COF assessment, an effective inspection method and range can be easily found. In this paper, the calculation of the Pof is improved for accurate risk assessment. A modified semi-quantitative risk assessment was carried out for boiler facilities of thermal power plants, and the next maintenance schedules for the equipment were decided.

  1. Prediction of Maintenance Period of Equipment Through Risk Assessment of Thermal Power Plants

    International Nuclear Information System (INIS)

    Song, Gee Wook; Kim, Bum Shin; Choi, Woo Song; Park, Myung Soo

    2013-01-01

    Risk-based inspection (RBI) is a well-known method that is used to optimize inspection activities based on risk analysis in order to identify the high-risk components of major facilities such as power plants. RBI, when implemented and maintained properly, improves plant reliability and safety while reducing unplanned outages and repair costs. Risk is given by the product of the probability of failure (Pof) and the consequence of failure (COF). A semi-quantitative method is generally used for risk assessment. Semi-quantitative risk assessment complements the low accuracy of qualitative risk assessment and the high expense and long calculation time of quantitative risk assessment. The first step of RB I is to identify important failure modes and causes in the equipment. Once these are defined, the Pof and COF can be assessed for each failure. During Pof and COF assessment, an effective inspection method and range can be easily found. In this paper, the calculation of the Pof is improved for accurate risk assessment. A modified semi-quantitative risk assessment was carried out for boiler facilities of thermal power plants, and the next maintenance schedules for the equipment were decided

  2. Geothermal Risk Reduction via Geothermal/Solar Hybrid Power Plants. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, Daniel [Idaho National Lab. (INL), Idaho Falls, ID (United States); Mines, Greg [Idaho National Lab. (INL), Idaho Falls, ID (United States); Turchi, Craig [National Renewable Energy Lab. (NREL), Golden, CO (United States); Zhu, Guangdong [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-11-01

    There are numerous technical merits associated with a renewable geothermal-solar hybrid plant concept. The performance of air-cooled binary plants is lowest when ambient temperatures are high due to the decrease in air-cooled binary plant performance that occurs when the working fluid condensing temperature, and consequently the turbine exhaust pressure, increases. Electrical power demand is generally at peak levels during periods of elevated ambient temperature and it is therefore especially important to utilities to be able to provide electrical power during these periods. The time periods in which air-cooled binary geothermal power plant performance is lowest generally correspond to periods of high solar insolation. Use of solar heat to increase air-cooled geothermal power plant performance during these periods can improve the correlation between power plant output and utility load curves. While solar energy is a renewable energy source with long term performance that can be accurately characterized, on shorter time scales of hours or days it can be highly intermittent. Concentrating solar power (CSP), aka solar-thermal, plants often incorporate thermal energy storage to ensure continued operation during cloud events or after sunset. Hybridization with a geothermal power plant can eliminate the need for thermal storage due to the constant availability of geothermal heat. In addition to the elimination of the requirement for solar thermal storage, the ability of a geothermal/solar-thermal hybrid plant to share a common power block can reduce capital costs relative to separate, stand-alone geothermal and solar-thermal power plant installations. The common occurrence of long-term geothermal resource productivity decline provides additional motivation to consider the use of hybrid power plants in geothermal power production. Geothermal resource productivity decline is a source of significant risk in geothermal power generation. Many, if not all, geothermal resources

  3. Assessment of inhalation risk due to radioactivity released from coal-based thermal power plant

    International Nuclear Information System (INIS)

    Sahu, S.K.; Pandit, G.G.; Shukla, V.K.; Puranik, V.D.; Kushwaha, H.S.

    2006-01-01

    In India, the coal based thermal power plants have been the major source of power generation in the past and would continue for decades to come. As the coal contains naturally occurring primordial radionuclides the burning of pulverized coal to produce energy for generation of electricity in thermal power plants will result in the emission of a variety of natural radioactive elements into the environment in the vicinity of thermal power plants. In this paper we have used two different methods for characterization of uncertainty in inhalation risk to the general public around 10 Kms radius in the neighborhood of a coal-fired thermal power plant. (author)

  4. Fire risk analysis for nuclear power plants: Methodological developments and applications

    International Nuclear Information System (INIS)

    Kazarians, M.; Apostolakis, G.; Siv, N.O.

    1985-01-01

    A methodology to quantify the risk from fires in nuclear power plants is described. This methodology combines engineering judgment, statistical evidence, fire phenomenology, and plant system analysis. It can be divided into two major parts: (1) fire scenario identification and quantification, and (2) analysis of the impact on plant safety. This article primarily concentrates on the first part. Statistical analysis of fire occurrence data is used to establish the likelihood of ignition. The temporal behaviors of the two competing phenomena, fire propagation and fire detection and suppression, are studied and their characteristic times are compared. Severity measures are used to further specialize the frequency of the fire scenario. The methodology is applied to a switchgear room of a nuclear power plant

  5. RIMAP demonstration project. Risk-based life management of piping system in power plant Heilbronn

    International Nuclear Information System (INIS)

    Bareiss, J.; Buck, P.; Matschecko, B.; Jovanovic, A.; Balos, D.; Perunicic, M.

    2004-01-01

    In the framework of EU project RIMAP [Risk Based Inspection and Maintenance Procedures for European Industry (2000)] a new European Guideline for optimized risk based maintenance and inspection planning of industrial plants (RBLM, Risk Based Life Management) is being developed. The RIMAP project consists of the three clustered projects: - development (RTD); - demonstration (DEMO): - thematic network (TN). Current work and future, planned work in RIMAP demonstration project on applications of the RIMAP methodology in power plants are presented briefly in the first part of the paper. Also presented in the paper are the results of a preliminary analysis of piping system in power plant Heilbronn using the concept of risk-based monitoring as part of overall concept of risk-based life management. Shortly the following issues are discussed in the paper: - identification of critical components; - application of a multilevel risk analysis (...from 'screening' to 'detailed analysis'); - determination of PoF (Probability of Failure); - determination of CoF (Consequence of Failure); - optimation of inspection and maintenance plan. From our experience with the application of the RIMAP methodology the following conclusions can be drawn: The use of risk-based methods in inspection and maintenance of piping systems in power plants gives transparency to the decision making process and gives an optimized maintenance policy based on current state of the components. The results of the work clearly show the power of the proposed method for concentration on critical items: out of 64 monitored components 5 were selected for intermediate analysis and only 1 for the detailed analysis (probabilistic high temperature fracture mechanics)

  6. Risk perception among nuclear power plant employees

    International Nuclear Information System (INIS)

    Fields, C.D.

    1989-01-01

    Radiation protection training and general employee training within the nuclear industry are designed to reduce workers' concerns about radiation and to develop skills that will protect against unwarranted exposures. Inaccurate perceptions about radiation by workers can cause a lack of adequate concern or exaggerated fears, which in turn can result in unnecessary radiation exposure to the worker or co-workers. The purpose of the study is threefold: (a) to identify health and safety concerns among nuclear power plant employees, (b) to discover variables that influence the perception of risk among employees, and (c) to ascertain if attitudes of the family, community, and the media affect workers' perception of risk. Workers identified five areas of concern: shift work, radiation, industrial safety, stress, and sabotage

  7. Use of probabilistic risk assessment in expert system usage for nuclear power plant safety

    International Nuclear Information System (INIS)

    Uhrig, R.E.

    1987-01-01

    The introduction of probability risk assessments (PRA's) to nuclear power plants in the Rasmussen Report (WASH-1400) gave us a means of evaluating the risk to the public associated with the operation of nuclear power plants, at least on a relative basis. While the choice of the ''source term'' and methodology in a PRA significantly influence the absolute probability and the consequences of core melt, comparison of two PRA calculations for two configurations of the same plant, carried out on a consistent basis, can be readily identify the increase in risk associated with going from one configuration of a plant to another by removing components or systems from service. This ratio of core melt probabilities (assuming no recovery of failed systems) obtained from two PRA calculations for different configurations was the criterion (called ''risk factor'') chosen as a basis for making a decision in an expert system as to what mitigating action, if any, would be taken to avoid a trip situation from developing. PRISIM was developed by JBF Associates of Knoxville under the sponsorship of the NRC as a system for Resident Inspectors at nuclear power plants to provide them with a relative safety status of the plant under all configurations. PRISIM calculated the risk factor---the ration of core melt probabilities of the plant under the current configuration relative to the normal configuration with all systems functioning---using an algorithm that emulates the results of the original PRA. It also presents time and core melt (assuming no recovery of systems or components)

  8. Pathogenic free-living amoebae in a closed-loop power plant; risk assessment and risk management

    International Nuclear Information System (INIS)

    Cabanes, P.; Pernin, P.

    1998-01-01

    Since 1980, the water used for cooling in French power plants has been tested for pathogenic amoebae, especially Naegleria fowleri, the causative agent of Primary Amoebic Meningoencephalitis (PAM), a rapid fatal disease of the central nervous system. The replacement of brass condensers by stainless steel condensers resulted in increased Naegleria fowleri development, to a density of as much as 3000 l -1 in the Dampierre power plant cooling water. Downstream from Dampierre, the maximum detected density of this amoeba during the summer of 1995 was 80 l -1 , at low river flow. The replacement of a second condenser in 1996 at the same power plant was expected to double the amoebae concentration in the river. The hypothetical PAM risk for swimmers was then predicted to be 10 -4 per swim. To reduce the risk continuous chlorination of the closed-loop cooling system was implemented at a free residual chlorine level in the range of 0.3-0.5 mg.l -1 . Naegleria fowleri concentrations decreased immediately and thereafter remained under 4 l -1 . Total residual chlorine and chlorinated organic compounds were also monitored in the evaluation of the environmental impact of this preventive action. (authors)

  9. An assessment of mercury emissions and health risks from a coal-fired power plant

    Energy Technology Data Exchange (ETDEWEB)

    Fthenakis, V.M.; Lipfert, F.W.; Moskowitz, P.D.; Saroff, L. [Brookhaven National Laboratory, Upton, NY (United States)

    1995-12-01

    Title III of the 1990 Clean Air Act Amendments (CAAA) directed the US Environmental Protection Agency (EPA) to evaluate the rate and effect of mercury emissions in the atmosphere and technologies to control the emissions. The US DOE sponsored a risk assessment project at Brookhaven (BNL) to evaluate health risks of mercury emissions from coal combustion. Methylmercury (MeHg) is the compound predominantly responsible for human exposure to atmospheric mercury in the United States, through fish ingestion. In the BNL study, health risks to adults resulting from Hg emissions from a hypothetical coal-fired power plant were estimated using probabilistic risk assessment techniques. This study showed that the effects of emissions of a single large power plant may double the background exposures to MeHg resulting from consuming fish obtained from a localized are near the power plant. Even at these more elevated exposure levels, the attributable incidence in mild neurological symptoms (paresthesia) was estimated to be quite small, especially when compared with the estimated background incidence in the population. 29 refs., 5 figs., 2 tabs.

  10. An assessment of mercury emissions and health risks from a coal-fired power plant

    International Nuclear Information System (INIS)

    Fthenakis, V.M.; Lipfert, F.W.; Moskowitz, P.D.; Saroff, L.

    1995-01-01

    Title III of the 1990 Clean Air Act Amendments (CAAA) directed the US Environmental Protection Agency (EPA) to evaluate the rate and effect of mercury emissions in the atmosphere and technologies to control the emissions. The US DOE sponsored a risk assessment project at Brookhaven (BNL) to evaluate health risks of mercury emissions from coal combustion. Methylmercury (MeHg) is the compound predominantly responsible for human exposure to atmospheric mercury in the United States, through fish ingestion. In the BNL study, health risks to adults resulting from Hg emissions from a hypothetical coal-fired power plant were estimated using probabilistic risk assessment techniques. This study showed that the effects of emissions of a single large power plant may double the background exposures to MeHg resulting from consuming fish obtained from a localized are near the power plant. Even at these more elevated exposure levels, the attributable incidence in mild neurological symptoms (paresthesia) was estimated to be quite small, especially when compared with the estimated background incidence in the population. 29 refs., 5 figs., 2 tabs

  11. Architecture and design of third Qinshan nuclear power plant risk monitor

    Energy Technology Data Exchange (ETDEWEB)

    Wang, F.; Li, Y.; Wang, J.; Wang, J.; Hu, L. [Inst. of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei, Anhui, 230031 (China); School of Nuclear Science and Technology, Univ. of Science and Technology of China, No.350 Shushanhu Road, Shushan District, Hefei, Anhui, 230031 (China)

    2012-07-01

    Risk monitor is a real-time analysis tool to determine the point-in-time risk based on actual plant configuration, which is an important application of PSA (Probabilistic Safety Assessment). In this study the status and development trend of risk monitor were investigated and a risk monitor named TQRM (Third Qinshan nuclear power plant Risk Monitor) was developed. The B/S architecture and the two key computing methods pre-solved and resolving PSA model method adopted in TQRM were introduced. The functions and technical features were also presented. Now TQRM has been on-line for more than one year and used in the operation and maintenance of TQNPP. The experience demonstrates that TQRM's results are accurate and real-time, the architecture is stable, and it could be extended and maintained conveniently for any other Risk-Informed Application. (authors)

  12. Reactor safety study. An assessment of accident risks in U.S. commercial nuclear power plants. Executive summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1975-10-01

    The Reactor Safety Study was sponsored by the U. S. Atomic Energy Commission to estimate the public risks that could be involved in potential accidents in commercial nuclear power plants of the type now in use. It was performed under the independent direction of Professor Norman C. Rasmussen of the Massachusetts Institute of Technology. The risks had to be estimated, rather than measured, because although there are about 50 such plants now operating, there have been no nuclear accidents to date resulting in significant releases of radioactivity in U.S. commercial nuclear power plants. The objective of the study was to make a realistic estimate of these risks and, to provide perspective, to compare them with non-nuclear risks to which our society and its individuals are already exposed. This information may be of help in determining the future reliance by society on nuclear power as a source of electricity. The results from this study suggest that the risks to the public from potential accidents in nuclear power plants are comparatively small.

  13. Reactor safety study. An assessment of accident risks in U.S. commercial nuclear power plants. Executive summary

    International Nuclear Information System (INIS)

    1975-10-01

    The Reactor Safety Study was sponsored by the U. S. Atomic Energy Commission to estimate the public risks that could be involved in potential accidents in commercial nuclear power plants of the type now in use. It was performed under the independent direction of Professor Norman C. Rasmussen of the Massachusetts Institute of Technology. The risks had to be estimated, rather than measured, because although there are about 50 such plants now operating, there have been no nuclear accidents to date resulting in significant releases of radioactivity in U.S. commercial nuclear power plants. The objective of the study was to make a realistic estimate of these risks and, to provide perspective, to compare them with non-nuclear risks to which our society and its individuals are already exposed. This information may be of help in determining the future reliance by society on nuclear power as a source of electricity. The results from this study suggest that the risks to the public from potential accidents in nuclear power plants are comparatively small

  14. Risk-informed technology developments for nuclear power plants within the ASME in 2000-2001

    International Nuclear Information System (INIS)

    Wesley Rowley, C.; Balkey, K.R.

    2001-01-01

    The purpose of this paper is to provide information on developments within the ASME to support risk-informing NRC regulations for nuclear power plants. This paper builds on a publication at ICONE-8 that discussed ASME risk-informed nuclear power plant initiatives, both in Research and in Codes and Standards, particularly those related to risk-informing Part 50 of the 10 CFR (Code of federal regulations). During the past year, the ASME BNCS formed a Task Force to focus the Society's efforts to support risk-informing 10 CFR Part 50. Key efforts underway that are guided by the task force include finalizing the ASME PRA (probability risk assessment) Standard, developing a Code Case to risk-inform the repair, replacement, and modification activities for ASME components, and developing a Code Case to risk-inform the safety classification of pressure boundary components. Several other initiatives are also under investigation such as introducing risk insights into other ASME nuclear codes and standards supported by appropriate research and technical basis information. Supplementary information will also be provided to update an initial high level plan of ASME risk-informed initiatives for nuclear power plants that was presented at ICONE-8, including plans to communicate these risk-informed technology developments to the public. The authors included and acknowledged contributions from several other cognizant members of the ASME BNCS (board on nuclear codes standards) Task Group on RIP50 in the paper. (authors)

  15. Risk averse optimal operation of a virtual power plant using two stage stochastic programming

    International Nuclear Information System (INIS)

    Tajeddini, Mohammad Amin; Rahimi-Kian, Ashkan; Soroudi, Alireza

    2014-01-01

    VPP (Virtual Power Plant) is defined as a cluster of energy conversion/storage units which are centrally operated in order to improve the technical and economic performance. This paper addresses the optimal operation of a VPP considering the risk factors affecting its daily operation profits. The optimal operation is modelled in both day ahead and balancing markets as a two-stage stochastic mixed integer linear programming in order to maximize a GenCo (generation companies) expected profit. Furthermore, the CVaR (Conditional Value at Risk) is used as a risk measure technique in order to control the risk of low profit scenarios. The uncertain parameters, including the PV power output, wind power output and day-ahead market prices are modelled through scenarios. The proposed model is successfully applied to a real case study to show its applicability and the results are presented and thoroughly discussed. - Highlights: • Virtual power plant modelling considering a set of energy generating and conversion units. • Uncertainty modelling using two stage stochastic programming technique. • Risk modelling using conditional value at risk. • Flexible operation of renewable energy resources. • Electricity price uncertainty in day ahead energy markets

  16. A societal risk analysis model for nuclear power plants

    International Nuclear Information System (INIS)

    Klopp, George T.

    2004-01-01

    A review of the last decade and a half reveals that the nuclear power industry, world wide, has devoted increased attention to the concepts of reactor risk, probabilistic risk assessment (PRA), and cost benefit analyses. Millions of dollars have been spent by the industry and by regulatory agencies on studies of specific plants, research into severe accident behavior, and the development of national risk goals. In the United States, there is a major effort underway to evaluate each operating nuclear plant using PRA and the latest information on severe accident behavior. This effort constitutes a search for 'outliers' or vulnerabilities which may be profitably addressed by changes to plant design or operation. The question, then, immediately arises: How much is it reasonable to spend on this particular 'outlier?' The answer to this question, in each case, calls for some systematic vehicle for evaluating the worth of risk reduction. In turn, this calls for some means to look at all aspects of risk using a common yardstick or unit of measure. A review of past practices in such evaluations leads one directly to the classical cost benefit analyses which rarely use any guideline more comprehensive than the old $1000 per person-rem. The real costs of the TMI accident point to a need for a more realistic treatment. The BoPhal accident, the Chernobyl accident, and the Exxon Valdez accident highlight risk aspects previously not explored in detail and further support the postulate that a better method is mandated by history

  17. A risk-informed perspective on deterministic safety analysis of nuclear power plants

    International Nuclear Information System (INIS)

    Wan, P.T.

    2009-01-01

    In this work, the deterministic safety analysis (DSA) approach to nuclear safety is examined from a risk-informed perspective. One objective of safety analysis of a nuclear power plant is to demonstrate via analysis that the risks to the public from events or accidents that are within the design basis of the power plant are within acceptable levels with a high degree of assurance. This nuclear safety analysis objective can be translated into two requirements on the risk estimates of design basis events or accidents: the nominal risk estimate to the public must be shown to be within acceptable levels, and the uncertainty in the risk estimates must be shown to be small on an absolute or relative basis. The DSA approach combined with the defense-in-depth (DID) principle is a simplified safety analysis approach that attempts to achieve the above safety analysis objective in the face of potentially large uncertainties in the risk estimates of a nuclear power plant by treating the various uncertainty contributors using a stylized conservative binary (yes-no) approach, and applying multiple overlapping physical barriers and defense levels to protect against the release of radioactivity from the reactor. It is shown that by focusing on the consequence aspect of risk, the previous two nuclear safety analysis requirements on risk can be satisfied with the DSA-DID approach to nuclear safety. It is also shown the use of multiple overlapping physical barriers and defense levels in the traditional DSA-DID approach to nuclear safety is risk-informed in the sense that it provides a consistently high level of confidence in the validity of the safety analysis results for various design basis events or accidents with a wide range of frequency of occurrence. It is hoped that by providing a linkage between the consequence analysis approach in DSA with a risk-informed perspective, greater understanding of the limitation and capability of the DSA approach is obtained. (author)

  18. US power plant sites at risk of future sea-level rise

    International Nuclear Information System (INIS)

    Bierkandt, R; Levermann, A; Auffhammer, M

    2015-01-01

    Unmitigated greenhouse gas emissions may increase global mean sea-level by about 1 meter during this century. Such elevation of the mean sea-level enhances the risk of flooding of coastal areas. We compute the power capacity that is currently out-of-reach of a 100-year coastal flooding but will be exposed to such a flood by the end of the century for different US states, if no adaptation measures are taken. The additional exposed capacity varies strongly among states. For Delaware it is 80% of the mean generated power load. For New York this number is 63% and for Florida 43%. The capacity that needs additional protection compared to today increases by more than 250% for Texas, 90% for Florida and 70% for New York. Current development in power plant building points towards a reduced future exposure to sea-level rise: proposed and planned power plants are less exposed than those which are currently operating. However, power plants that have been retired or canceled were less exposed than those operating at present. If sea-level rise is properly accounted for in future planning, an adaptation to sea-level rise may be costly but possible. (letter)

  19. On nuclear power plant uprating

    International Nuclear Information System (INIS)

    Ho, S. Allen; Bailey, James V.; Maginnis, Stephen T.

    2004-01-01

    Power uprating for commercial nuclear power plants has become increasingly attractive because of pragmatic reasons. It provides quick return on investment and competitive financial benefits, while involving low risks regarding plant safety and public objection. This paper briefly discussed nuclear plant uprating guidelines, scope for design basis analysis and engineering evaluation, and presented the Salem nuclear power plant uprating study for illustration purposes. A cost and benefit evaluation of the Salem power uprating was also included. (author)

  20. Integrated Level 3 risk assessment for the LaSalle Unit 2 nuclear power plant

    International Nuclear Information System (INIS)

    Payne, A.C. Jr.; Brown, T.D.; Miller, L.A.

    1991-01-01

    An integrated Level 3 probabilistic risk assessment (PRA) was performed on the LaSalle County Station nuclear power plant using state-of-the-art PRA analysis techniques. The objective of this study was to provide an estimate of the risk to the offsite population during full power operation of the plant and to include a characterization of the uncertainties in the calculated risk values. Uncertainties were included in the accident frequency analysis, accident progression analysis, and the source term analysis. Only weather uncertainties were included in the consequence analysis. In this paper selected results from the accident frequency, accident progression, source term, consequence, and integrated risk analyses are discussed and the methods used to perform a fully integrated Level 3 PRA are examined. LaSalle County Station is a two-unit nuclear power plant located 55 miles southwest of Chicago, Illinois. Each unit utilizes a Mark 2 containment to house a General Electric 3323 MWt BWR-5 reactor. This PRA, which was performed on Unit 2, included internal as well as external events. External events that were propagated through the risk analysis included earthquakes, fires, and floods. The internal event accident scenarios included transients, transient-induced LOCAs (inadvertently stuck open relief valves), anticipated transients without scram, and loss of coolant accidents

  1. Nuclear power plant of Fessenheim: evaluation of the seismic risk; Centrale Nucleaire de Fessenheim: appreciation du risque sismique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    The seismic risk taken into account during the sizing of the nuclear power plant of Fessenheim seems to have been under evaluated at this time. The revaluation of the seismic risk, as proposed, until this day by EDF in order to the third ten-year visit of the power plant, planned for 2009, leads to a significant under evaluation of the risk and then is not acceptable. The present expertise details point by point the weaknesses of these revaluation. The power plant has been sized in an elastic manner that is generally strongly for the safety side. It is imperative to proceed the most quickly as possible to a deep control of the seismic resistance of the power plant of Fessenheim and then after having proceeded to a revision of the seismic risk in taking into account the actual knowledge in this field. (N.C.)

  2. Probabilistic inhalation risk assessment due to radioactivity released from coal fired thermal power plants

    International Nuclear Information System (INIS)

    Tiwari, M.; Ajmal, P.Y.; Bhangare, R.C.; Sahu, S.K.; Pandit, G.G.

    2014-01-01

    This paper deals with assessment of radiological risk to the general public around in the neighborhood of a 1000 MWe coal-based thermal power plant. We have used Monte Carlo simulation for characterization of uncertainty in inhalation risk due to radionuclide escaping from the stack of thermal power plant. Monte Carlo simulation treats parameters as random variables bound to a given probabilistic distribution to evaluate the distribution of the resulting output. Risk assessment is the process that estimates the likelihood of occurrence of adverse effects to humans and ecological receptors as a result of exposure to hazardous chemical, radiation, and/or biological agents. Quantitative risk characterization involves evaluating exposure estimates against a benchmark of toxicity, such as a cancer slope factor. Risk is calculated by multiplying the carcinogenic slope factor (SF) of the radionuclide by the dose an individual receives. The collective effective doses to the population living in the neighborhood of coal-based thermal power plant were calculated using Gaussian plume dispersion model. Monte Carlo Analysis is the most widely used probabilistic method in risk assessment. The MCA technique treats any uncertain parameter as random variable that obeys a given probabilistic distribution. This technique is widely used for analyzing probabilistic uncertainty. In MCA computer simulation are used to combine multiple probability distributions associated with the dose and SF depicted in risk equation. Thus we get a probabilistic distribution for the risk

  3. Environmental impact due to nuclear power plants

    International Nuclear Information System (INIS)

    Kellermann, O.; Balfanz, H.P.

    1975-01-01

    The environmental impact due to nuclear power plants is smaller than that due to fossil-fired power plants. The risks of the nuclear power plant operation are determined by the quantity and the probability of the release of radioactive materials. According to the value, the risks of normal operation can be compared to the accident risks. An attempt should be made to effectively reduce the remaining risk at unfavourable sites with the emphasis on accidents with larger effects than design basis accidents. (orig./LH) [de

  4. Risk analysis of warehouse operation in a power plant through a Modified FMEA

    Directory of Open Access Journals (Sweden)

    Indrawati Sri

    2018-01-01

    Full Text Available Currently, electricity becomes basic needs for human’s life sustainability. Most of activities require electricity. Some power plant are demanded to be able to fulfil above necessity by distributing electricity as it required within time. Therefore, to accommodate good performance, it needs assessment on risk analysis, specifically at the warehousing division. A risk analysis is needed for assuring a good performance warehouse. A Modified FMEA method is used to analyse the risk. This method id done by identifying sources and root causes of a problem based on the value of risk priority number (RPN. The research is conducted in an Indonesian power plant, located in West Java. There are 10 types of failure modes. The result shows that the failure mode priority is inventory discrepancies. There are no difference ranking on the most impacted failure to be prioritized using FMEA and modified FMEA method.

  5. Study on communicating risk information obtained from PSA within nuclear power plants

    International Nuclear Information System (INIS)

    Nunogane, Nobuaki; Onoue, Akira; Kojima, Shigeo

    2000-01-01

    In this study, the communication of PSA information in nuclear power plants (NPPs), namely, how the risk information obtained from the probabilistic safety assessment (PSA) should be presented and communicated to plant personnel, was examined assuming that the safety management system based on the risk information was introduced to NPPs. This is called PSA communication. First, when risk-informed safety management is to be introduced into NPPs, plant personnel should have sufficient related knowledge. In order to provide such knowledge to the personnel through training, risk information is classified into three types: basic information, detailed information and task information. A hierarchical risk information summary for reporting, coordinating and communicating tasks is proposed. In this summary, the concerns of those who have received the information are placed at the top and the related risk information positioned below. At the same time, and by way of a trial, the risk information relating to on-line maintenance (OLM) is prepared. In order to enhance the safety-consciousness and the safety of the entire plant, specific plans such as 'risk tags' which indicate the safety significance of equipment is proposed. Finally, a guideline providing examination procedures for developing detailed PSA communication plans is introduced. (author)

  6. VGB congress 'power plants 2003'. Generation gap - risk and challenge for the electricity market

    International Nuclear Information System (INIS)

    Anon.

    2003-01-01

    The VGB Congress 'Power Plants 2003' took place in Copenhagen from 15th to 17th September 2003. The motto of this year's Congress was 'Generation Gap - Risk and Challenge for the Electricity Market'. More than 800 participants took the opportunity for discussion and information in the plenary and technical lectures 'Market and Competition' and 'Technology, Operation and Environment'. Apart from the special features of the Scandinavian and Baltic electricity market, the main focus was on papers reflecting the situation of nuclear power (Finland), operating experience with new power plants, new materials for power plant construction, application of renewables and issues of climate protection. The Congress was again rounded off by technical visits and a side programme. (orig.) [de

  7. Risk factors during construction of power plants using renewable energy sources

    Directory of Open Access Journals (Sweden)

    Nefedova Lyudmila Veniaminovna

    2016-12-01

    Full Text Available The authors consider main characteristics of modern development of renewable energy sources (RES. It is dedicated that there are some technical and economic barriers to the widespread use of renewable energy. For example, RES are inconstancy in time and space and have low density of energy flow. High capital intensity and cost price, long-term construction, a considerable degree of different kinds of risk, lack of competitiveness with hydrocarbon species generation in the existing regulatory environment are also inherent to RES. The role of the regulatory framework is shown according to perspective plans of construction of power plants using renewable energy sources. The main requirements which are applied to measures of state support of construction industry of renewable energy development are formulated. Current condition of construction industry of RES in Russia is assessed. The problems of risks which arise during construction of renewable energy facilities according to results of practical use of RES are discussed. And it is rather important to use stage assessment for the construction phase of the project during risk analysis of construction of alternative energy sources. The main groups of RES risks are described. The importance of regulatory and resource risks for effective development of renewable energy in Russia according to the method of strategic planning with the identification of the adverse effects of gradation factors are determined. The analysis of financial risks types and methods of its management during construction power generation projects based on different types of renewable energy resources are made. In the end of the article the authors make a conclusion, that the development of projects for the construction of power plants with the use of innovative technical solutions to ensure minimal risks to the environment and safe operation in various climatic conditions is a priority.

  8. The safety of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    Do nuclear power plants present an unjustifiable risk Can there be confidence in their safety The Uranium Institute invited a group of senior safety experts from eight different Western countries operating different types of reactors to provide an authoritative explanation for non-specialists of the basic principles of reactor safety, their application and their implications. The report presents the group's opinion on the level of safety achieved in the Western nuclear power plants with which the authors are directly familiar. Although many of the points made may well also be true for non-Western reactors, the report does not cover them except where specifically stated. It does describe and discuss the causes of the Chernobyl disaster. It does not compare nuclear power with other fuels, nor does it deal with its benefits, since however great the benefits from the peaceful use of nuclear power, and its own advantages over other fuels, they could not compensate for lack of safety. The conclusion reached is that the risk associated with electricity production at nuclear power plants can be kept very low. Proper use of the extensive knowledge available today can guarantee operation of nuclear power plants at very high safety levels, carrying very low risks, both to health and of contamination of the environment: risks that are continually lowered by upgrading existing plants and their operation, and by the design of future power plants. (author).

  9. Multi-Level Risk Assessment of a Power Plant Gas Turbine Applying ...

    African Journals Online (AJOL)

    Multi-Level Risk Assessment of a Power Plant Gas Turbine Applying the Criticality Index Model. ... Journal of the Nigerian Association of Mathematical Physics ... This study has carefully shown and expressed a step by step computation of the severity level of the Turbine component parts, using the Criticality Index model.

  10. Methods for estimating risks to nuclear power plants from shipping

    International Nuclear Information System (INIS)

    Walker, D.H.; Hartman, M.G.; Robbins, T.R.

    1975-01-01

    Nuclear power plants sited on land near shipping lanes or offshore can be exposed to potential risks if there is nearby ship or barge traffic which involves the transport of hazardous cargo. Methods that have been developed for estimating the degree of risk are summarized. Of concern are any accidents which could lead to a release or spill of the hazardous cargo, or to an explosion. A probability of occurrence of the order of 10 -7 per year is a general guideline which has been used to judge whether or not the risk from hazards created by accidents is acceptable. This guideline has been followed in the risk assessment discussed in this paper. 19 references

  11. ESP and NOAH: computer programs for flood-risk analysis of nuclear power plants

    International Nuclear Information System (INIS)

    Wagner, D.P.; Montague, D.F.; Rooney, J.J.; Fussell, J.B.; Baker, L.S.

    1982-06-01

    This report describes a computer program package that aids in assessing the impact of floods on risk from nuclear power plants. The package consists of two distinct computer programs: ESP and NOAH. The ESP program improves the efficiency of a flood analysis by screening accident sequences and identifying accident sequences that are potentially significant contributors to risk in the event of a flood. Input to ESP includes accident sequences from an existing risk assessment and flood screening criteria. The NOAH program provides detailed qualitative analysis of the plant systems identified by ESP. NOAH performs a qualitative flood simulation of the fault tree

  12. The application of CFD to hydrogen risk analysis in nuclear power plants

    International Nuclear Information System (INIS)

    Wang Hui; Han Xu; Chang Meng; Wang Xiaofeng; Wang Shuguo; Lu Xinhua; Wu Lin

    2013-01-01

    Status of the hydrogen risk analysis method is systemically summarized in this paper and the advantages and limits of CFD (Computational Fluid Dynamic) in hydrogen risk analysis is discussed. The international experimental programs on the CFD hydrogen risk analysis are introduced in this paper. The application of CFD to nuclear power plant (NPP) hydrogen risk analysis is introduced in detail by taking EPR and Ling'ao NPP for example. In these bases, the CFD development prospect of hydrogen risk analysis is also summarized in this paper. (authors)

  13. The risk of storing radioactive wastes from nuclear power plants

    International Nuclear Information System (INIS)

    Gruemm, H.

    1976-09-01

    Serious bottle-necks exist in the nuclear fuel cycle and will continue for the next decade. A total of 800 nuclear reactors are now in operation. 153 nuclear power plants represent an installed capacity of 70 GVe. Until 1985 five hundred nuclear power plants will be in operation from which up to this date 53.000 t uranium will have been discharged. Part of this will have to be reprocessed. Associated with the above mentioned amount are 500 t plutonium and 1.500 t highly radioactive wastes. Two risks for the population have to be considered: firstly, the effect of small amounts of radioactive substances released during normal operation of nuclear power plants (the annual dose is about 1 mrem per person). Secondly, the possibility of the release of great amounts of radioactivity during heavy accidents (the probability for which is extremely small). A series of feasible possibilities for conditioning are shown. Firstly, the wastes are packed in substances which are insoluble in water. Secondly, for low and medium wastes these can be mixed with concrete or bitumen and filled into stable containers. Thirdly, the wastes could also be solidified. Fourthly, the wastes could be enclosed in small glass spheres which are embedded in a metal matrix. (H.G.)

  14. Risk-informed assessment of regulatory and design requirements for future nuclear power plants. Annual report

    International Nuclear Information System (INIS)

    2000-01-01

    OAK B188 Risk-informed assessment of regulatory and design requirements for future nuclear power plants. Annual report. The overall goal of this research project is to support innovation in new nuclear power plant designs. This project is examining the implications, for future reactors and future safety regulation, of utilizing a new risk-informed regulatory system as a replacement for the current system. This innovation will be made possible through development of a scientific, highly risk-formed approach for the design and regulation of nuclear power plants. This approach will include the development and/or confirmation of corresponding regulatory requirements and industry standards. The major impediment to long term competitiveness of new nuclear plants in the U.S. is the capital cost component--which may need to be reduced on the order of 35% to 40% for Advanced Light Water Reactors (ALWRS) such as System 80+ and Advanced Boiling Water Reactor (ABWR). The required cost reduction for an ALWR such as AP600 or AP1000 would be expected to be less. Such reductions in capital cost will require a fundamental reevaluation of the industry standards and regulatory bases under which nuclear plants are designed and licensed. Fortunately, there is now an increasing awareness that many of the existing regulatory requirements and industry standards are not significantly contributing to safety and reliability and, therefore, are unnecessarily adding to nuclear plant costs. Not only does this degrade the economic competitiveness of nuclear energy, it results in unnecessary costs to the American electricity consumer. While addressing these concerns, this research project will be coordinated with current efforts of industry and NRC to develop risk-informed, performance-based regulations that affect the operation of the existing nuclear plants; however, this project will go further by focusing on the design of new plants

  15. Risk-informed assessment of regulatory and design requirements for future nuclear power plants. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-08-01

    OAK B188 Risk-informed assessment of regulatory and design requirements for future nuclear power plants. Annual report. The overall goal of this research project is to support innovation in new nuclear power plant designs. This project is examining the implications, for future reactors and future safety regulation, of utilizing a new risk-informed regulatory system as a replacement for the current system. This innovation will be made possible through development of a scientific, highly risk-formed approach for the design and regulation of nuclear power plants. This approach will include the development and/or confirmation of corresponding regulatory requirements and industry standards. The major impediment to long term competitiveness of new nuclear plants in the U.S. is the capital cost component--which may need to be reduced on the order of 35% to 40% for Advanced Light Water Reactors (ALWRS) such as System 80+ and Advanced Boiling Water Reactor (ABWR). The required cost reduction for an ALWR such as AP600 or AP1000 would be expected to be less. Such reductions in capital cost will require a fundamental reevaluation of the industry standards and regulatory bases under which nuclear plants are designed and licensed. Fortunately, there is now an increasing awareness that many of the existing regulatory requirements and industry standards are not significantly contributing to safety and reliability and, therefore, are unnecessarily adding to nuclear plant costs. Not only does this degrade the economic competitiveness of nuclear energy, it results in unnecessary costs to the American electricity consumer. While addressing these concerns, this research project will be coordinated with current efforts of industry and NRC to develop risk-informed, performance-based regulations that affect the operation of the existing nuclear plants; however, this project will go further by focusing on the design of new plants.

  16. Thermal power plants and environment

    International Nuclear Information System (INIS)

    1997-01-01

    Recent versions of the air quality models which are reviewed and approved from the Environmental Protection Agency (EPA) are analysed in favour of their application in simple and complex terrain, different meteorological conditions and modifications in the sources of pollutant emissions. Improvement of the standard methods for analysis of the risks affecting the environment from different energy sources has been carried out. The application of the newly introduced model enabled (lead to performing) risk analysis of the coal power plants compared to other types of energy sources. Detailed investigation of the risk assessment and perception from coal power plants, has been performed and applied to the Macedonian coal power plants. Introducing the concept of 'psychological pollution', a modification of the standard models and programs for risk assessment from various energy sources has been suggested (proposed). The model has been applied to REK Bitola, where statistically relevant differences in relation to the control groups have been obtained. (Original)

  17. Severe accident risks: An assessment for five US nuclear power plants

    International Nuclear Information System (INIS)

    1991-01-01

    This report summarizes an assessment of the risks from severe accidents in five commercial nuclear power plants in the United State. These risks are measured in a number of ways, including: the estimated frequencies of core damage accidents from internally initiated accidents and externally initiated accidents for two of the plants; the performance of containment structures under severe accident loadings; the potential magnitude of radionuclide releases and offsite consequences of such accidents; and the overall risk (the product of accident frequencies and consequences). Supporting this summary report are a large number of reports written under contract to NRC that provide the detailed discussion of the methods used and results obtained in these risk studies. This report, Volume 3, contains two appendices. Appendix D summarizes comments received, and staff responses, on the first (February 1987) draft of NUREG-1150. Appendix E provides a similar summary of comments and responses, but for the second (June 1989) version of the report

  18. Wind power plant system services

    DEFF Research Database (Denmark)

    Basit, Abdul; Altin, Müfit

    Traditionally, conventional power plants have the task to support the power system, by supplying power balancing services. These services are required by the power system operators in order to secure a safe and reliable operation of the power system. However, as in the future the wind power...... is going more and more to replace conventional power plants, the sources of conventional reserve available to the system will be reduced and fewer conventional plants will be available on-line to share the regulation burden. The reliable operation of highly wind power integrated power system might...... then beat risk unless the wind power plants (WPPs) are able to support and participate in power balancing services. The objective of this PhD project is to develop and analyse control strategies which can increase the WPPs capability to provide system services, such as active power balancing control...

  19. Methodology for flood risk analysis for nuclear power plants

    International Nuclear Information System (INIS)

    Wagner, D.P.; Casada, M.L.; Fussell, J.B.

    1984-01-01

    The methodology for flood risk analysis described here addresses the effects of a flood on nuclear power plant safety systems. Combining the results of this method with the probability of a flood allows the effects of flooding to be included in a probabilistic risk assessment. The five-step methodology includes accident sequence screening to focus the detailed analysis efforts on the accident sequences that are significantly affected by a flood event. The quantitative results include the flood's contribution to system failure probability, accident sequence occurrence frequency and consequence category occurrence frequency. The analysis can be added to existing risk assessments without a significant loss in efficiency. The results of two example applications show the usefulness of the methodology. Both examples rely on the Reactor Safety Study for the required risk assessment inputs and present changes in the Reactor Safety Study results as a function of flood probability

  20. Risk analysis of geothermal power plants using Failure Modes and Effects Analysis (FMEA) technique

    International Nuclear Information System (INIS)

    Feili, Hamid Reza; Akar, Navid; Lotfizadeh, Hossein; Bairampour, Mohammad; Nasiri, Sina

    2013-01-01

    Highlights: • Using Failure Modes and Effects Analysis (FMEA) to find potential failures in geothermal power plants. • We considered 5 major parts of geothermal power plants for risk analysis. • Risk Priority Number (RPN) is calculated for all failure modes. • Corrective actions are recommended to eliminate or decrease the risk of failure modes. - Abstract: Renewable energy plays a key role in the transition toward a low carbon economy and the provision of a secure supply of energy. Geothermal energy is a versatile source as a form of renewable energy that meets popular demand. Since some Geothermal Power Plants (GPPs) face various failures, the requirement of a technique for team engineering to eliminate or decrease potential failures is considerable. Because no specific published record of considering an FMEA applied to GPPs with common failure modes have been found already, in this paper, the utilization of Failure Modes and Effects Analysis (FMEA) as a convenient technique for determining, classifying and analyzing common failures in typical GPPs is considered. As a result, an appropriate risk scoring of occurrence, detection and severity of failure modes and computing the Risk Priority Number (RPN) for detecting high potential failures is achieved. In order to expedite accuracy and ability to analyze the process, XFMEA software is utilized. Moreover, 5 major parts of a GPP is studied to propose a suitable approach for developing GPPs and increasing reliability by recommending corrective actions for each failure mode

  1. External hazards in reliability and risk assessment of nuclear power plants

    International Nuclear Information System (INIS)

    Stevenson, J.D.

    1977-01-01

    It is current practice in the design of nuclear power generating stations to protect against the effects of significant natural and man-made external hazards which can occur at the plant site in excess of those hazards normally considered for conventional facilities. This paper is meant to identify those postulated external hazards typically considered in nuclear facility design. The paper also attempts to fulfill the following four objectives: (1) Define the current state of the art in applying reliability and risk analysis to determine external hazard design requirements. (2) Provide a ready source of literature references applicable to probabilistic design for extreme loads. (3) Provide some quantitative probability assessment estimates of external hazards. (4) Develop exclusion criteria by which postulated external hazards can be eliminated as a design basis. Rigorous evaluation of the design requirements for nuclear power plant facilities based on principles of probability and risk analysis is just beginning. It is hoped these techniques will be used more extensively in the future to provide a more rational basis for developing design requirements. (orig.) [de

  2. Lifetime extension of ageing nuclear power plants. Entering a new era of risk. Report comissionned by Greenpeace

    International Nuclear Information System (INIS)

    2014-03-01

    The abbreviated version of the Greenpeace report on the lifetime extension of aging nuclear power plants - entering a new era of risk - covers the following topics: age of the nuclear power plants in Europe, covered amounts of insurance in Europe in case of a nuclear accident, progress of the ageing of nuclear power plants, and the power up-rating of nuclear reactors. The economy of aged reactors is discussed in connection with the lifetime extension and the liabilities for the aging reactors.

  3. Current perspectives on nuclear power plant risks and the use of risk-based information in regulation

    Energy Technology Data Exchange (ETDEWEB)

    Ross, D F; Ernst, M L; Murphy, J

    1987-08-01

    For the first five years, the U.S. Nuclear Regulatory Commission has supported extensive studies of severe accidents. One outcome of this work is a set of advanced method for analyzing the probabilities, source terms, consequences, and risks of such accidents. These methods are being applied to a set of six U.S. commercial nuclear power plants, covering a wide spread of nuclear steam supply systems and containment designs. This work is to be documented in the Reactor Risk Reference Document, NUREG-1150, and supporting contractors reports. The methods being used for NUREG-1150, and some initial plant results, are briefly described in this paper.

  4. RIMAP demonstration project. Pat. 1: Risk based life management of piping system in power plant Heilbronn

    International Nuclear Information System (INIS)

    Bareiss, J.; Puck, P.; Matschecko, B.; Jovanovic, A.; Balos, D.; Perunicic

    2003-01-01

    In the framework of EU project RIMAP [1] a new European Guideline for optimized risk based maintenance and inspection planning of industrial plants (RBLM - Risk Based Life Management) is being developed. The RIMAP project consists of the three clustered projects: development (RTD), demonstration (DEMO) and thematic network (TN). Current work and future, planned work in RIMAP demonstration project on applications of the RIMAP methodology in power plants are presented briefly in the first part of the paper. Also presented in the paper are the results of a preliminary analysis of piping system in power plant Heilbronn using the concept of risk-based monitoring as part of overall concept of risk-based life management. Shortly the following issues are discussed in the paper: identification of critical components, application of a multilevel risk analysis (..from ''screening'' to ''detailed analysis''), determination of PoF - Probability of Failure, determination of COF - Consequence of Failure and optimation of inspection and maintenance plan. (orig.)

  5. Nuclear power plants in populated areas

    International Nuclear Information System (INIS)

    Wachsmann, F.

    1973-01-01

    The article first deals with the permanently increasing demand for electical power. Considering the ever growing energy demand which can no longer be covered by conventional power plants, it has become necessary to set up nuclear power plants of larger range. The author presents in a survey the basic function of nuclear power plants as well as the resulting risks and safety measures. The author concludes that according to present knowledge there is no more need to erect nuclear power plants outside densely populated urban areas but there is now the possibility of erecting nuclear power plants in densely populated areas. (orig./LH) [de

  6. Review of problems and methods for radiation risk assessment in the environment of a nuclear power plant

    International Nuclear Information System (INIS)

    Grgic, M.

    1966-01-01

    Radiation impact on the nuclear power plant environment is a very important problem which has to be solved during design and construction. Damage that could be caused by release of radioactive material into the environment should be estimated and the magnitude of nuclear and radiation risk of the power plant should be evaluated. In general the accuracy of estimation is rather poor due to statistical fluctuations of the conditions which influence radioactivity expansion in the environment, especially in the air. Different uncertainties and unresolved problems influence the inaccuracy. Since any real risk should be extremely small compared to potential risk i.e. risk induced by nuclear power plant without any safety measures, even inaccurate estimations are very useful. Method for environmental radiation risk assessment is based on relatively simple models of radiation expansion in the environment and in the air. These models are theoretically solved but they are based on relatively limited number of experimental data. Assessment of the radiation effects on the population health and mortality is an important problem [sl

  7. Risk-averse formulations and methods for a virtual power plant

    KAUST Repository

    Lima, Ricardo M.; Conejo, Antonio J.; Langodan, Sabique; Hoteit, Ibrahim; Knio, Omar M.

    2017-01-01

    In this paper we address the optimal operation of a virtual power plant using stochastic programming. We consider one risk-neutral and two risk-averse formulations that rely on the conditional value at risk. To handle large-scale problems, we implement two decomposition methods with variants using single- and multiple-cuts. We propose the utilization of wind ensembles obtained from the European Centre for Medium Range Weather Forecasts (ECMWF) to quantify the uncertainty of the wind forecast. We present detailed results relative to the computational performance of the risk-averse formulations, the decomposition methods, and risk management and sensitivities analysis as a function of the number of scenarios and risk parameters. The implementation of the two decomposition methods relies on the parallel solution of subproblems, which turns out to be paramount for computational efficiency. The results show that one of the two decomposition methods is the most efficient.

  8. Risk-averse formulations and methods for a virtual power plant

    KAUST Repository

    Lima, Ricardo M.

    2017-12-15

    In this paper we address the optimal operation of a virtual power plant using stochastic programming. We consider one risk-neutral and two risk-averse formulations that rely on the conditional value at risk. To handle large-scale problems, we implement two decomposition methods with variants using single- and multiple-cuts. We propose the utilization of wind ensembles obtained from the European Centre for Medium Range Weather Forecasts (ECMWF) to quantify the uncertainty of the wind forecast. We present detailed results relative to the computational performance of the risk-averse formulations, the decomposition methods, and risk management and sensitivities analysis as a function of the number of scenarios and risk parameters. The implementation of the two decomposition methods relies on the parallel solution of subproblems, which turns out to be paramount for computational efficiency. The results show that one of the two decomposition methods is the most efficient.

  9. Nuclear power plant insurance - experience and loss statistics

    International Nuclear Information System (INIS)

    Feldmann, J.; Dangelmaier, P.

    1982-01-01

    Nuclear power plants are treated separately when concluding insurance contracts. National insurance pools have been established in industrial countries, co-operating on an international basis, for insuring a nuclear power plant. In combined property insurance, the nuclear risk is combined with the fire risk. In addition, there are the engineering insurances. Of these, the one of significance for nuclear power plants is the machinery insurance, which can be covered on the free insurance market. Nuclear power plants have had fewer instances of damage than other, conventional installations. (orig.) [de

  10. The role of insurance and risk management in new power plant projects

    International Nuclear Information System (INIS)

    Ryan, R.

    1988-01-01

    Insurance, and other risk management techniques, can be used to facilitate the financing and construction of power plant projects. This paper describes certain techniques, then it concentrates on insurance based solutions. The objective of this paper is to point out how the insurance industry can help small power producers. First, the standard insurance coverages will be reviewed. Then coverages that have been specifically designed for the alternative energy, cogeneration and small power producing industries will be explained. Some real life examples will be discussed to show how the coverages really work

  11. An application of risk-informed evaluation on MOVs and AOVs for Taiwan BWR-type nuclear power plants

    International Nuclear Information System (INIS)

    Ting, K.; Chen, K.T.; Li, Y.C.; Hwang, S.H.; Chien, F.T.; Kang, J.C.

    2008-01-01

    Implementing a risk-informed inservice testing (RI-IST) program provides a good aspect to the nuclear power plant licensee as an alternating program in the current ASME Section XI and 10 CFR 50.55a relevant testing programs. RI-IST concentrates testing resources on highly significant components, reduces excess testing burden, increases plant's availability, decreases dose rate on the plant's staff and also reduces cost on plant's operation and maintenance under nuclear safety expectations. Furthermore, RI-IST also gives a feature on prospective licensing change basis to a nuclear power plant's licensee. This study will focus on safety-related and PRA-molded motor-operated valves (MOVs) and air-operated valves (AOVs) under the inservice testing program in boiling water reactor (BWR)-type nuclear power plant. As MOVs and AOVs have crucial safety functions throughout the nuclear power plant's safety systems, the steady operation and performance of MOVs and AOVs will definitely ensure that the nuclear power plant operates under safety expectations; therefore, this is the key reason to implement risk-informed evaluation for MOVs and AOVs in this study and being able to provide the safety significance classification for MOVs and AOVs under the current IST program to the plant's management. As a pilot study of RI-IST, the methodology of qualitative assessment will incorporate with probabilistic risk assessment (PRA) analyzing MOVs' and AOVs' safety significance within the current PRA model. The evaluating result will then classify its safety significance into a high-safety significant component (HSSC) and a low-safety significant component (LSSC) for MOVs and AOVs based on relevant regulatory criteria. With this initiating achievement, it can provide a cornerstone for further studies on the other types of valves and pumps in RI-IST program and also provide a valuable reference as proposing license change to the licensee

  12. Assessing Risk-Based Performance Indicators in Safety-Critical Systems for Nuclear Power Plants

    OpenAIRE

    TONT Gabriela

    2011-01-01

    The paper proposes framework for a multidisciplinary nuclear risk and safety assessment by modeling uncertainty and combining diverse evidence provided in such a way that it could be used to represent an entire argument about a system's dependability. The identified safety issues are being treated by means of probabilistic safety assessment (PSA). The behavior simulation of power plant in thepresence of risk factors is analyzed from the vulnerability, risk and functional safety viewpoints, hi...

  13. Health Risk Assessment of Nitrogen Dioxide and Sulfur Dioxide Exposure from a New Developing Coal Power Plant in Thailand

    Directory of Open Access Journals (Sweden)

    Tin Thongthammachart

    2017-07-01

    Full Text Available Krabi coal-fired power plant is the new power plant development project of the Electricity Generating Authority of Thailand (EGAT. This 800 megawatts power plant is in developing process. The pollutants from coal-fired burning emissions were estimated and included in an environmental impact assessment report. This study aims to apply air quality modeling to predict nitrogen dioxide (NO2 and sulfur dioxide (SO2 concentration which could have health impact to local people. The health risk assessment was studied following U.S. EPA regulatory method. The hazard maps were created by ArcGIS program. The results indicated the influence of the northeast and southwest monsoons and season variation to the pollutants dispersion. The daily average and annual average concentrations of NO2 and SO2 were lower than the NAAQS standard. The hazard quotient (HQ of SO2 and NO2 both short-term and long-term exposure were less than 1. However, there were some possibly potential risk areas indicating in GIS based map. The distribution of pollutions and high HI values were near this power plant site. Although the power plant does not construct yet but the environment health risk assessment was evaluated to compare with future fully developed coal fire plant.

  14. Benchmarking Nuclear Power Plants

    International Nuclear Information System (INIS)

    Jakic, I.

    2016-01-01

    One of the main tasks an owner have is to keep its business competitive on the market while delivering its product. Being owner of nuclear power plant bear the same (or even more complex and stern) responsibility due to safety risks and costs. In the past, nuclear power plant managements could (partly) ignore profit or it was simply expected and to some degree assured through the various regulatory processes governing electricity rate design. It is obvious now that, with the deregulation, utility privatization and competitive electricity market, key measure of success used at nuclear power plants must include traditional metrics of successful business (return on investment, earnings and revenue generation) as well as those of plant performance, safety and reliability. In order to analyze business performance of (specific) nuclear power plant, benchmarking, as one of the well-established concept and usual method was used. Domain was conservatively designed, with well-adjusted framework, but results have still limited application due to many differences, gaps and uncertainties. (author).

  15. Effect of the Fukushima nuclear accident on the risk perception of residents near a nuclear power plant in China.

    Science.gov (United States)

    Huang, Lei; Zhou, Ying; Han, Yuting; Hammitt, James K; Bi, Jun; Liu, Yang

    2013-12-03

    We assessed the influence of the Fukushima nuclear accident (FNA) on the Chinese public's attitude and acceptance of nuclear power plants in China. Two surveys (before and after the FNA) were administered to separate subsamples of residents near the Tianwan nuclear power plant in Lianyungang, China. A structural equation model was constructed to describe the public acceptance of nuclear power and four risk perception factors: knowledge, perceived risk, benefit, and trust. Regression analysis was conducted to estimate the relationship between acceptance of nuclear power and the risk perception factors while controlling for demographic variables. Meanwhile, we assessed the median public acceptable frequencies for three levels of nuclear events. The FNA had a significant impact on risk perception of the Chinese public, especially on the factor of perceived risk, which increased from limited risk to great risk. Public acceptance of nuclear power decreased significantly after the FNA. The most sensitive groups include females, those not in public service, those with lower income, and those living close to the Tianwan nuclear power plant. Fifty percent of the survey respondents considered it acceptable to have a nuclear anomaly no more than once in 50 y. For nuclear incidents and serious incidents, the frequencies are once in 100 y and 150 y, respectively. The change in risk perception and acceptance may be attributed to the FNA. Decreased acceptance of nuclear power after the FNA among the Chinese public creates additional obstacles to further development of nuclear power in China and require effective communication strategies.

  16. Cooperation of nuclear, thermal and hydroelectric power plants in the power system

    International Nuclear Information System (INIS)

    1984-01-01

    The conference heard 36 papers of which 23 were incorporated in INIS. The subjects discussed were: the development of power industry in Czechoslovakia, methods of statistical analysis of data regarding nuclear power plant operation, the incorporation of WWER nuclear power plants in the power supply system, the standardization of nuclear power plants, the service life of components, use of nuclear energy sources, performance of the reactor accident protection system, the use of nuclear power and heating plants in Hungary, risk analysis, optimization of nuclear power plants, accidents caused by leakage of the primary and secondary circuit. (J.P.)

  17. Survey on the use of configuration risk and safety management tools at nuclear power plants. Final report

    International Nuclear Information System (INIS)

    Fleming, K.N.; Read, J.W.; Dagan, W.J.; Bidwell, D.A.

    1998-09-01

    In order to provide input to Electricite de France's (EDF) evaluation of the use of configuration safety and risk management tools in the French plants and to collect information to guide the EPRI efforts to provide useful tools for the EPRI member utilities and international partners, a joint effort to survey US and selected non-US nuclear power stations was conducted. This survey examined the use of various approaches, techniques, and software tools that are being used to evaluate the safety and risk aspects of plant configuration changes and configuration changes during plant outages as well as during power operation. The use of these tools has increased in recent years as a result of efforts to optimize plant maintenance programs, improve plant safety, and increase plant reliability and availability. This report provides the results of the survey of 37 organizations covering 54 nuclear plant sites and 97 reactor units

  18. Alternative off-site power supply improves nuclear power plant safety

    International Nuclear Information System (INIS)

    Gjorgiev, Blaže; Volkanovski, Andrija; Kančev, Duško; Čepin, Marko

    2014-01-01

    Highlights: • Additional power supply for mitigation of the station blackout event in NPP is used. • A hydro power plant is considered as an off-site alternative power supply. • An upgrade of the probabilistic safety assessment from its traditional use is made. • The obtained results show improvement of nuclear power plant safety. - Abstract: A reliable power system is important for safe operation of the nuclear power plants. The station blackout event is of great importance for nuclear power plant safety. This event is caused by the loss of all alternating current power supply to the safety and non-safety buses of the nuclear power plant. In this study an independent electrical connection between a pumped-storage hydro power plant and a nuclear power plant is assumed as a standpoint for safety and reliability analysis. The pumped-storage hydro power plant is considered as an alternative power supply. The connection with conventional accumulation type of hydro power plant is analysed in addition. The objective of this paper is to investigate the improvement of nuclear power plant safety resulting from the consideration of the alternative power supplies. The safety of the nuclear power plant is analysed through the core damage frequency, a risk measure assess by the probabilistic safety assessment. The presented method upgrades the probabilistic safety assessment from its common traditional use in sense that it considers non-plant sited systems. The obtained results show significant decrease of the core damage frequency, indicating improvement of nuclear safety if hydro power plant is introduced as an alternative off-site power source

  19. Identification of seismically risk-sensitive systems and components in nuclear power plants: feasibility study

    International Nuclear Information System (INIS)

    Azarm, M.; Boccio, J.; Farahzad, P.

    1983-06-01

    An approach for the identification of risk-sensitive components in a nuclear power plant during and after a seismic event is described. Application of the methodology to two hypothetical power plants - a Boiling Water Reactor and a Pressurized Water Reactor - are presented and the results are given in tabular and graphical form. Conclusions drawn and lessons learned through the course of this study, based on the relative importance of various accident scenarios and sensitivity analyses, are discussed. In addition, the areas that may need further investigation are identified

  20. Risks of potential accidents of nuclear power plants in Europe

    NARCIS (Netherlands)

    Slaper H; Eggink GJ; Blaauboer RO

    1993-01-01

    Over 200 nuclear power plants for commercial electricity production are presently operational in Europe. The 1986 accident with the nuclear power plant in Chernobyl has shown that severe accidents with a nuclear power plant can lead to a large scale contamination of Europe. This report is focussed

  1. Possibilities of Utilization the Risk – Based Techniques in the Field of Offshore Wind Power Plants

    Directory of Open Access Journals (Sweden)

    Przemysław Kacprzak

    2014-09-01

    Full Text Available In the article the risk-based concept that may be applicable to offshore wind power plants has been presented. The aim of the concept is to aid designers in the early design and retrofit phases of the project in case of lack or insufficient information in relevant international standards. Moreover the initial classification of components within main system parts of offshore wind power plant has been performed. Such classification is essential in order to apply risk-based concept. However further scientific researches need to be performed in that field to develop detailed concept useful for future practical applications.

  2. Perceived nuclear risk, organizational commitment, and appraisals of management: A study of nuclear power plant personnel

    International Nuclear Information System (INIS)

    Kivimaeki, M.; Kalimo, R.; Salminen, S.

    1995-01-01

    This study examined to what extent nuclear risk perceptions, organizational commitment (OC), and appraisals of management are associated with each other among nuclear power plant personnel. The sample consisted of 428 nuclear power plant workers who completed a questionnaire at their workplace. Perceived nuclear risk and OC were most closely related to the appraisals of the top management of the organization. As the trust in and satisfaction with the top management increased, perceived nuclear safety and acceptance of the organizational goals and values heightened. This result is discussed in the context of industrial safety management. 29 refs., 2 tabs

  3. Circumstances in a nuclear power plant. Organization of risk and institutionalization of safety

    International Nuclear Information System (INIS)

    Wessblad, H.

    1999-01-01

    Risk societies are made of risk organisations. This dissertation is an ethnographic study of a risk organisation, of a nuclear power plant. Risk organizations have larger demands on their organization than traditional companies have. Risk societies, to come or already present, have new political agendas. Within a risk society the major task is to reduce and distribute the negative side effects of industrial production, not to increase and distribute well-fare in society, as it has been in an industrial society. This is a study of a risk organisation claimed to produce these negative side effects. The title of this thesis relates to specific occasions in the organisation. The branch concept, circumstances, defines 'situations beyond normal performance', which are to be reported to the nuclear authorities. These circumstances are rarely endangering man or material, but given the nature of nuclear power production, they have a potential to escalate to something larger. This dissertation focuses on how the organisation deals with these issues and reproduces safety as something taken-for-granted. The material is gathered using participant observation of different functions in the plant. The work is based on narration of situations, meetings, interviews, and small talk etc, in every-day-interaction. The dissertation describes how business-as-usual produce safety. It is a description of how values, norms, attitudes, ideas, knowledge are produced and reproduced. These issues are discussed mainly in an institutional theory perspective. What has become apparent is that functions governed by routines and instructions tend to be more flexible and reflecting than those dealing with new tasks, such as problem solving projects. Thus, these new projects tend to reproduce earlier established procedures. Through the narration of the various functions of the plant joined with theoretical discussions, different themes have been found describing how the organisation deals with

  4. Environmental risk assessment of airborne emission from chinese coal-fired power plants with public health detriment criteria

    International Nuclear Information System (INIS)

    He Huimin; Pan Ziqiang; Zhang Yongxing; Xia Yihua

    1997-01-01

    On the basis of investigation of types of dust removers and their efficiency in Chinese coal-fired power plants, human health detriment of airborne non-radioactive and radioactive emissions from the power plants is assessed with public health detriment assessment method. The results show that the risk is primarily from airborne non-radioactive emission

  5. Risk-based analysis methods applied to nuclear power plant technical specifications

    International Nuclear Information System (INIS)

    Wagner, D.P.; Minton, L.A.; Gaertner, J.P.

    1989-01-01

    A computer-aided methodology and practical applications of risk-based evaluation of technical specifications are described. The methodology, developed for use by the utility industry, is a part of the overall process of improving nuclear power plant technical specifications. The SOCRATES computer program uses the results of a probabilistic risk assessment or a system-level risk analysis to calculate changes in risk due to changes in the surveillance test interval and/or the allowed outage time stated in the technical specification. The computer program can accommodate various testing strategies (such as staggered or simultaneous testing) to allow modeling of component testing as it is carried out at the plant. The methods and computer program are an integral part of a larger decision process aimed at determining benefits from technical specification changes. These benefits can include cost savings to the utilities by reducing forced shutdowns and decreasing labor requirements for test and maintenance activities, with no adverse impacts on risk. The methodology and the SOCRATES computer program have been used extensively toe valuate several actual technical specifications in case studies demonstrating the methods. Summaries of these applications demonstrate the types of results achieved and the usefulness of the risk-based evaluation in improving the technical specifications

  6. PCB transformer fires: the risk in nuclear power plants

    International Nuclear Information System (INIS)

    Blackmon, K.

    1988-01-01

    It is estimated that 1/2 of the present nuclear power plants operate with PCB-filled transformer equipment. In an attempt to obtain better estimates of clean-up costs in a nuclear power plant under reasonable-loss scenarios, a study was commissioned. This study was a joint venture between Blackmon-Mooring Steamatic Technologies, Inc., (BMS-TECH) and M and M Protection Consultants. This joint study was conducted at a typical pressurized-water reactor plant consisting of two 1000-MW units. Three specific scenarios were selected and analyzed for this typical power plant. These scenarios were: (1) an electrical failure of a transformer in an isolated switch gear room; (2) a transformer exposed to a 55-gallon transient combustion oil fire in the auxiliary building; and (3) a PCB transformer involved in a major turbine lube fire in the turbine building. Based on results of this study, the insurance carriers for this industry implemented an adjustment in their rate structures for nuclear power plants that have PCB equipment

  7. The control of operational risk in nuclear power plant operations - Some cross-cultural perspectives

    International Nuclear Information System (INIS)

    Suchard, A.; Rochlin, G.

    1992-01-01

    The operation of nuclear power plants requires the management of a complex technology under exacting performance and safety criteria. Organizations operating nuclear power plants are faced with the challenge of simultaneously meeting technical, organizational, and social demands, striving toward perfection in a situation where learning by trial and error can be too costly. In this process, they interact with regulatory bodies who seek to help minimize operational risk by imposing and upholding safety standards. The character of this interaction differs in various countries, as does the larger cultural setting. The study generally pursued the question of how organizations operating complex and demanding technologies adapt to such requirements and circumstances, and how they can succeed in delivering nearly error-free performance. One aspect of this study includes the comparison of organizational and cultural environments for nuclear power plant operations in the US, France, Germany, Sweden, and Switzerland. The research involved in-depth, continuous observations on location and interviews with plant personnel, especially control operators, at one plant in each country

  8. A cyber security risk assessment for the design of I and C system in nuclear power plants

    International Nuclear Information System (INIS)

    Song, Jae Gu; Lee, Jung Woon; Lee, Cheal Kwon; Kwon, Kee Choon; Lee, Dong Young

    2012-01-01

    The applications of computers and communication system and network technologies in nuclear power plants have expanded recently. This application of digital technologies to the instrumentation and control systems of nuclear power plants brings with it the cyber security concerns similar to other critical infrastructures. Cyber security risk assessments for digital instrumentation and control systems have become more crucial in the development of new systems and in the operation of existing systems. Although the instrumentation and control systems of nuclear power plants are similar to industrial control systems, the former have specifications that differ from the latter in terms of architecture and function, in order to satisfy nuclear safety requirements, which need different methods for the application of cyber security risk assessment. In this paper, the characteristics of nuclear power plant instrumentation and control systems are described, and the considerations needed when conducting cyber security risk assessments in accordance with the life cycle process of instrumentation and control systems are discussed. For cyber security risk assessments of instrumentation and control systems, the activities and considerations necessary for assessments during the system design phase or component design and equipment supply phase are presented in the following 6 steps: 1) System Identification and Cyber Security Modeling, 2) Asset and Impact Analysis, 3) Threat Analysis, 4) Vulnerability Analysis, 5) Security Control Design, and 6) Penetration test. The results from an application of the method to a digital reactor protection system are described.

  9. A cyber security risk assessment for the design of I and C system in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Song, Jae Gu; Lee, Jung Woon; Lee, Cheal Kwon; Kwon, Kee Choon; Lee, Dong Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-12-15

    The applications of computers and communication system and network technologies in nuclear power plants have expanded recently. This application of digital technologies to the instrumentation and control systems of nuclear power plants brings with it the cyber security concerns similar to other critical infrastructures. Cyber security risk assessments for digital instrumentation and control systems have become more crucial in the development of new systems and in the operation of existing systems. Although the instrumentation and control systems of nuclear power plants are similar to industrial control systems, the former have specifications that differ from the latter in terms of architecture and function, in order to satisfy nuclear safety requirements, which need different methods for the application of cyber security risk assessment. In this paper, the characteristics of nuclear power plant instrumentation and control systems are described, and the considerations needed when conducting cyber security risk assessments in accordance with the life cycle process of instrumentation and control systems are discussed. For cyber security risk assessments of instrumentation and control systems, the activities and considerations necessary for assessments during the system design phase or component design and equipment supply phase are presented in the following 6 steps: 1) System Identification and Cyber Security Modeling, 2) Asset and Impact Analysis, 3) Threat Analysis, 4) Vulnerability Analysis, 5) Security Control Design, and 6) Penetration test. The results from an application of the method to a digital reactor protection system are described.

  10. Impact of structural aging on seismic risk assessment of reinforced concrete structures in nuclear power plants

    International Nuclear Information System (INIS)

    Ellingwood, B.; Song, J.

    1996-03-01

    The Structural Aging Program is addressing the potential for degradation of concrete structural components and systems in nuclear power plants over time due to aging and aggressive environmental stressors. Structures are passive under normal operating conditions but play a key role in mitigating design-basis events, particularly those arising from external challenges such as earthquakes, extreme winds, fires and floods. Structures are plant-specific and unique, often are difficult to inspect, and are virtually impossible to replace. The importance of structural failures in accident mitigation is amplified because such failures may lead to common-cause failures of other components. Structural condition assessment and service life prediction must focus on a few critical components and systems within the plant. Components and systems that are dominant contributors to risk and that require particular attention can be identified through the mathematical formalism of a probabilistic risk assessment, or PRA. To illustrate, the role of structural degradation due to aging on plant risk is examined through the framework of a Level 1 seismic PRA of a nuclear power plant. Plausible mechanisms of structural degradation are found to increase the core damage probability by approximately a factor of two

  11. Protection of French nuclear power plants against flooding risks - 15307

    International Nuclear Information System (INIS)

    Barbaud, J.

    2015-01-01

    In France, the flooding risk has been taken into account since the beginning of the nuclear program and has been reinforced following operating feedback from French and international power plants. The main events which led to reinforcement were the partial flooding in the Blayais NPP that occurred in 1999 and the Fukushima accident in 2011. The current French fleet is composed of 58 PWR reactors located on 19 sites: 4 sites are sea side, 1 side is located on an estuary and all other are located on river side. The lessons learned from the Blayais event are: -) an update of the hazard evaluation of the risks, -) a new assessment of the sufficiency of the protective measures, and -) the taking into account of aggravating risks associated to support functions such as site inaccessibility, loss of off-site power, etc. The lessons learned from the Fukushima accident have confirmed and enhanced lessons from the Blayais event. In addition the Fukushima accident has underlined the need to have sufficient margins beyond the design to avoid cliff edge effects. The improvements implemented on the Blayais and the Belleville sites are detailed

  12. Affective imagery and acceptance of replacing nuclear power plants.

    Science.gov (United States)

    Keller, Carmen; Visschers, Vivianne; Siegrist, Michael

    2012-03-01

    This study examined the relationship between the content of spontaneous associations with nuclear power plants and the acceptance of using new-generation nuclear power plants to replace old ones. The study also considered gender as a variable. A representative sample of the German- and French-speaking population of Switzerland (N= 1,221) was used. Log-linear models revealed significant two-way interactions between the association content and acceptance, association content and gender, and gender and acceptance. Correspondence analysis revealed that participants who were opposed to nuclear power plants mainly associated nuclear power plants with risk, negative feelings, accidents, radioactivity, waste disposal, military use, and negative consequences for health and environment; whereas participants favoring nuclear power plants mainly associated them with energy, appearance descriptions of nuclear power plants, and necessity. Thus, individuals opposing nuclear power plants had both more concrete and more diverse associations with them than people who were in favor of nuclear power plants. In addition, participants who were undecided often mentioned similar associations to those participants who were in favor. Males more often expressed associations with energy, waste disposal, and negative health effects. Females more often made associations with appearance descriptions, negative feelings, and negative environmental effects. The results further suggest that acceptance of replacing nuclear power plants was higher in the German-speaking part of the country, where all of the Swiss nuclear power plants are physically located. Practical implications for risk communication are discussed. © 2011 Society for Risk Analysis.

  13. Computer codes to assess risks from nuclear power plants with LWR's

    International Nuclear Information System (INIS)

    Alonso, A.; Blanco, J.; Francia, L.; Gallego, E.; Morales, L.; Ortega, P.; Torres, C.

    1986-01-01

    The codes used to quantify risks from nuclear power plants are described. For QRA level 1 (quantitative risk assessment) qualitative and quantitative codes are described. Codes to estimate uncertainties, importance and dependent failures are also included. For QRA-level 2, the most important codes dealing with thermohydraulics, molten core and aerosols behaviour are described. For QRA-level 3 the list includes integrated as well as separate models. Only light water reactors are considered. The presentation is general but the authors describe with more detail those codes they are more familiar with or the ones they have created through their research effort. (author)

  14. Destructiveness criteria for seismic risk evaluation of nuclear power plant

    International Nuclear Information System (INIS)

    Saragoni, G.R.

    1995-01-01

    Two criteria of destructiveness for seismic risk evaluation of nuclear power plant are presented. The first one is a simple linear criterion that allows to compute average response spectra in terms of earthquake accelerogram characteristics. The second defines the destructiveness potential factor P D which measures the capacity of earthquake to produce nonlinear damage. This second criterion that shows large differences of destructiveness capacity for earthquake accelerograms of different seismic environment, specially between subductive and transcursive, is strongly recommended. (author). 8 refs., 1 fig. 1 tab

  15. Thermal Power Plant Performance Analysis

    CERN Document Server

    2012-01-01

    The analysis of the reliability and availability of power plants is frequently based on simple indexes that do not take into account the criticality of some failures used for availability analysis. This criticality should be evaluated based on concepts of reliability which consider the effect of a component failure on the performance of the entire plant. System reliability analysis tools provide a root-cause analysis leading to the improvement of the plant maintenance plan.   Taking in view that the power plant performance can be evaluated not only based on  thermodynamic related indexes, such as heat-rate, Thermal Power Plant Performance Analysis focuses on the presentation of reliability-based tools used to define performance of complex systems and introduces the basic concepts of reliability, maintainability and risk analysis aiming at their application as tools for power plant performance improvement, including: ·         selection of critical equipment and components, ·         defini...

  16. Risk-based management of remaining life of power plant components

    International Nuclear Information System (INIS)

    Roos, E.; Jovanovic, A.S.; Maile, K.; Auerkari, P.

    1999-01-01

    The paper describes application of different modules of the MPA-System ALIAS in risk-based management of remaining life of power plant components. The system allows comprehensive coverage of all aspects of the remaining life management, including also the risk analysis and risk management. In addition, thanks to the modular character of the system it is also possible to implement new methods: In the case described here, a new (probabilistic) method for determination of the next inspection time for the components exposed to creep loading has been developed and implemented in the system. Practical application of the method has shown (a) that the mean values obtained by the method fall into the range of results obtained by other methods (based on expert knowledge), and (b) that it is possible to quantify the probability of aberration from the mean values. This in turn allows quantifying the additional risks linked to e.g. prolonging of inspection intervals. (orig.) [de

  17. Nuclear power plants in post-war thought

    International Nuclear Information System (INIS)

    Toya, Hiroshi

    2015-01-01

    This paper overviews how nuclear power plants have been talked about in the post-war thought. Science and technology sometimes significantly change the thinking way of humans, and nuclear power generation is an extreme technology. This paper overviews how nuclear power plants and humans are correlated. The following three points are discussed as the major issues of contemporary thought over nuclear power plants. First, on the danger of nuclear power plants, the risk of destructive power that nuclear energy has, and the danger of unreasoning development in science and technology civilization are discussed. Second, on the ethics issues surrounding nuclear power plants, the ethics that are based on unbalanced power relations, and democratic responsibility ethics based on discussion ethics are discussed. Third, on the issues of nuclear power plants and imagination, the limitations of democratic discussion surrounding nuclear power plants, the formation of imagination commensurate with the destructive power of nuclear power plants, and the formation of imagination that can represent the distant future are discussed. (A.O.)

  18. Cost-benefit and risk-benefit assessment for nuclear power plants

    International Nuclear Information System (INIS)

    Eichholz, G.G.

    1976-01-01

    A cost benefit assessment is an essential part of the Environmental Impact Statement submitted as part of the licensing considerations for a nuclear facility. Such an assessment forms part of the initial decision to build a nuclear facility, enters critically into the selection of a suitable site, and ultimately forms part of the design procedures to optimize engineering solutions to deal with waste-heat dissipation, treatment methods for radioactive effluent control, and land and site use. Whereas the initial decision usually can be made in purely economic terms, the latter stages involve environmental and social issues that are not readily quantified and involve a qualitative judgment of what constitutes the least, readily achievable impact. The radiological impact of the plant on the surrounding population from the release of low-level effluents can be quantified and treated as a financial ''cost.'' Alternatively it can be treated as a ''risk'' and related to other risks modern man is subjected to and can be used as a means to establish site boundaries. Both cost-benefit and risk-benefit analyses represent essentially optimization approaches to the problem of making nuclear power plants economically competitive, socially and politically acceptable, and as safe or innocuous as one can reasonably make them

  19. Calculation of risk-based detection limits for radionuclides in the liquid effluents from Korean nuclear power plants

    International Nuclear Information System (INIS)

    Cheong, Jae Hak

    2017-01-01

    In order to review if present detection limits of radionuclides in liquid effluent from nuclear power plants are effective enough to warrant compliance with regulatory discharge limits, a risk-based approach is developed to derive a new detection limit for each radionuclide based on radiological criteria. Equations and adjustment factors are also proposed to discriminate the validity of the detection limits for multiple radionuclides in the liquid effluent with or without consideration of the nuclide composition. From case studies to three nuclear power plants in Korea with actual operation data from 2006 to 2015, the present detection limits have turned out to be effective for Hanul Unit 1 but may not be sensitive enough for Kori Unit 1 (8 out of 14 radionuclides) and Wolsong Unit 1 (9 out of 42 radionuclides). However, it is shown that the present detection limits for the latter two nuclear power plants can be justified, if credit is given to the radionuclide composition. Otherwise, consideration should be given to adjustment of the present detection limits. The risk-based approach of this study can be used to determine the validity of established detection limits of a specific nuclear power plant. (author)

  20. Development of safety culture by improving risk communication in a nuclear power plant

    International Nuclear Information System (INIS)

    Sugiman, Toshio; Yoshikawa, Hidekazu

    2004-01-01

    Safety culture is conceptually examined from the viewpoint of activity theory proposed by Engestroem. The theory is instrumental in broadening our scope of views to the extent that a particular (group of person(s) and his/her (their) environment are regarded as a part of activity of a larger collectivity consisting of people and their physical and institutional environments. Overwhelming orientation toward an unmanned plant is reflected in object → outcome and mediating artifacts in the structure of activity in a nuclear power plant while it is contradicted with another orientation toward the improvement of employee's ability in community, rules, and division of labor. Three possible ways to transform a currently dominant activity into a new form were suggested depending on a preliminary study of our research project headed by the seconds author. First, community of a nuclear power plant may as well be expanded to the extent that nuclear experts outside the plant, especially those working for a plant/equipment manufacturing company, can share information with workers inside the plant through internet system that has been developed in our project. Second, community of workplace may as well be reexamined concerning division of labor between a supervisor and subordinates. Among all, leader behaviors of a supervisor that were effective to reduce psychological stress of subordinates, which, in turn, make positive contribution to safety culture, were identified by a questionnaire survey. Last, a minority of workers who tend to take risks for radiation exposure more seriously than the majority and share similar risk cognition with ordinary citizens may as well be utilized as linking pin that brings a warning signal from both a minority of nuclear experts outside the plant and ordinary citizens to the majority of workers in the plant who tend to be devoted to implementing everyday job. (author)

  1. Risks and challenges associated with the design and construction of a nuclear power plant

    International Nuclear Information System (INIS)

    Liebana Martinez, B.; Armas Garcia, A.; Martinez Gozalo, I.

    2011-01-01

    The construction of a nuclear power plant project, considering the period prior to the operation of the plant, requires a very strict risk control to ensure compliance with a series of challenges. The present paper identifying the most important challenges facing the construct ability and license requirements of the process, identifying the interfaces and proposing a methodology of construction to meet the challenge of a construction process in 5 years.

  2. Fire Risk Scoping Study: Investigation of nuclear power plant fire risk, including previously unaddressed issues

    International Nuclear Information System (INIS)

    Lambright, J.A.; Nowlen, S.P.; Nicolette, V.F.; Bohn, M.P.

    1989-01-01

    An investigation of nuclear power plant fire risk issues raised as a result of the USNRC sponsored Fire Protection Research Program at Sandia National Laboratories has been performed. The specific objectives of this study were (1) to review and requantify fire risk scenarios from four fire probabilistic risk assessments (PRAs) in light of updated data bases made available as a result of USNRC sponsored Fire Protection Research Program and updated computer fire modeling capabilities, (2) to identify potentially significant fire risk issues that have not been previously addressed in a fire risk context and to quantify the potential impact of those identified fire risk issues where possible, and (3) to review current fire regulations and plant implementation practices for relevance to the identified unaddressed fire risk issues. In performance of the fire risk scenario requantifications several important insights were gained. It was found that utilization of a more extensive operational experience base resulted in both fire occurrence frequencies and fire duration times (i.e., time required for fire suppression) increasing significantly over those assumed in the original works. Additionally, some thermal damage threshold limits assumed in the original works were identified as being nonconservative based on more recent experimental data. Finally, application of the COMPBRN III fire growth model resulted in calculation of considerably longer fire damage times than those calculated in the original works using COMPBRN I. 14 refs., 2 figs., 16 tabs

  3. The application of availability analysis to nuclear power plants

    International Nuclear Information System (INIS)

    Brooks, A.C.

    1984-01-01

    The use of probabilistic risk analysis (PRA) to assess the risks from nuclear power plants is now well established. Considerably less attention has been given so far to the use of availability analysis techniques. The economics of power generation are now such that with nuclear power currently supplying a substantial fraction of power in many countries, increasing attention is being paid to improving plant availability. This paper presents a technique for systematically identifying the areas in which measures to improve plant availability will be most effective. (author)

  4. Safety Assessment - Swedish Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Kjellstroem, B. [Luleaa Univ. of Technology (Sweden)

    1996-12-31

    After the reactor accident at Three Mile Island, the Swedish nuclear power plants were equipped with filtered venting of the containment. Several types of accidents can be identified where the filtered venting has no effect on the radioactive release. The probability for such accidents is hopefully very small. It is not possible however to estimate the probability accurately. Experiences gained in the last years, which have been documented in official reports from the Nuclear Power Inspectorate indicate that the probability for core melt accidents in Swedish reactors can be significantly larger than estimated earlier. A probability up to one in a thousand operating years can not be excluded. There are so far no indications that aging of the plants has contributed to an increased accident risk. Maintaining the safety level with aging nuclear power plants can however be expected to be increasingly difficult. It is concluded that the 12 Swedish plants remain a major threat for severe radioactive pollution of the Swedish environment despite measures taken since 1980 to improve their safety. Closing of the nuclear power plants is the only possibility to eliminate this threat. It is recommended that until this is done, quantitative safety goals, same for all Swedish plants, shall be defined and strictly enforced. It is also recommended that utilities distributing misleading information about nuclear power risks shall have their operating license withdrawn. 37 refs.

  5. Safety Assessment - Swedish Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kjellstroem, B.

    1996-01-01

    After the reactor accident at Three Mile Island, the Swedish nuclear power plants were equipped with filtered venting of the containment. Several types of accidents can be identified where the filtered venting has no effect on the radioactive release. The probability for such accidents is hopefully very small. It is not possible however to estimate the probability accurately. Experiences gained in the last years, which have been documented in official reports from the Nuclear Power Inspectorate indicate that the probability for core melt accidents in Swedish reactors can be significantly larger than estimated earlier. A probability up to one in a thousand operating years can not be excluded. There are so far no indications that aging of the plants has contributed to an increased accident risk. Maintaining the safety level with aging nuclear power plants can however be expected to be increasingly difficult. It is concluded that the 12 Swedish plants remain a major threat for severe radioactive pollution of the Swedish environment despite measures taken since 1980 to improve their safety. Closing of the nuclear power plants is the only possibility to eliminate this threat. It is recommended that until this is done, quantitative safety goals, same for all Swedish plants, shall be defined and strictly enforced. It is also recommended that utilities distributing misleading information about nuclear power risks shall have their operating license withdrawn. 37 refs

  6. Probabilistic safety assessment technology for commercial nuclear power plant security evaluation

    International Nuclear Information System (INIS)

    Liming, J.K.; Johnson, D.H.; Dykes, A.A.

    2004-01-01

    Commercial nuclear power plant physical security has received much more intensive treatment and regulatory attention since September 11, 2001. In light of advancements made by the nuclear power industry in the field of probabilistic safety assessment (PSA) for its power plants over that last 30 years, and given the many examples of successful applications of risk-informed regulation at U. S. nuclear power plants during recent years, it may well be advisable to apply a 'risk-informed' approach to security management at nuclear power plants from now into the future. In fact, plant PSAs developed in response to NRC Generic Letter 88-20 and related requirements are used to help define target sets of critical plant safety equipment in our current security exercises for the industry. With reasonable refinements, plant PSAs can be used to identify, analyze, and evaluate reasonable and prudent approaches to address security issues and associated defensive strategies at nuclear power plants. PSA is the ultimate scenario-based approach to risk assessment, and thus provides a most powerful tool in identifying and evaluating potential risk management decisions. This paper provides a summary of observations of factors that are influencing or could influence cost-effective or 'cost-reasonable' security management decision-making in the current political environment, and provides recommendations for the application of PSA tools and techniques to the nuclear power plant operational safety response exercise process. The paper presents a proposed framework for nuclear power plant probabilistic terrorist risk assessment that applies these tools and techniques. (authors)

  7. Hydrogen risk reduction in Nuclear power plant

    International Nuclear Information System (INIS)

    Movahed, M.A.; Travis, J.R.

    1999-01-01

    In case of a severe accident in a nuclear power plant with core melt and hydrogen production, the hydrogen risk is one of the main concerns. It may jeopardize the containment integrity due to violent deflagration that can lead to DDT (Deflagration Detonation Transient) or even detonation of proper hydrogen mitigation means are not available. The design of the EPR (European Pressurized water Reactor) Hydrogen mitigation and control system is based on the lumped parameter code WAVCO and the 3D code GASFLOW. The concept consists of recombiners and igniters to cope with all scenarios including those without steam. The system has been checked to avoid DDT by the 7λ criteria that's implemented in GASFLOW. Future analysis could deal with determining dynamic pressure loads, if appropriate, and some sensitivity studies to check the hydrogen control measures with respect to different source locations and mass flow rates. Also a conditional criterion for determining the likelihood of fast deflagration should be developed. (author)

  8. Safety goals for commercial nuclear power plants

    International Nuclear Information System (INIS)

    Roe, J.W.

    1988-01-01

    In its official policy statement on safety goals for the operation of nuclear power plants, the Nuclear Regulatory Commission (NRC) set two qualitative goals, supported by two quantitative objectives. These goals are that (1) individual members of the public should be provided a level of protection from the consequences of nuclear power plant operation such that individuals bear no significant additional risk to life and health; and (2) societal risks to life and health from nuclear power plant operation should be comparable to or less than the risks of generating electricity by viable competing technologies and should not be a significant addition to other societal risks. As an alternative, this study proposes four quantitative safety goals for nuclear power plants. It begins with an analysis of the NRC's safety-goal development process, a key portion of which was devoted to delineating criteria for evaluating goal-development methods. Based on this analysis, recommendations for revision of the NRC's basic benchmarks for goal development are proposed. Using the revised criteria, NRC safety goals are evaluated, and the alternative safety goals are proposed. To further support these recommendations, both the NRC's goals and the proposed goals are compared with the results of three major probabilistic risk assessment studies. Finally, the potential impact of these recommendations on nuclear safety is described

  9. Evaluation and communication of potential risk of radionuclide contamination of foods after Fukushima nuclear power plant accident

    International Nuclear Information System (INIS)

    Sekizawa, Jun; Nakamura, Yumiko

    2011-01-01

    A large scale nuclear power plant accident happened after the great earthquake with a huge tsunami in the Eastern part of Japan in March 2011. Potential risk from radionuclide contamination in foods after the nuclear power plant accident was estimated using data of radiological food contamination from the Ministry of Health, Labour and Welfare. Data analyzed by combining nuclide, food, level of radiation detection, period, age-classified population, were compared to provisional index levels of radionuclides, and existing contamination levels in food by natural radioactive potassium. Health risk was shown to be very low or negligible considering presence of background radiological exposure from foods and the environment. Appropriate explanation of risk to various stakeholders of the society is imperative and results of trials were reported. (author)

  10. An Overview of Risk Quantification Issues for Digitalized Nuclear Power Plants using a Static Fault Tree

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hyun Gook; Kim, Man Cheol; Lee, Seung Jun; Lee, Ho Jung; Eom, Heung Seop; Chol, Jong Gyun; Jang, Seung Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-08-15

    Risk caused by safety-critical instrumentation and control (I and C) systems considerably affects overall plant risk. As digitalization of safety-critical systems in nuclear power plants progresses, a risk model of a digitalized safety system is required and must be included in a plant safety model in order to assess this risk effect on the plant. Unique features of a digital system cause some challenges in risk modeling. This article aims at providing an overview of the issues related to the development of a static fault-tree-based risk model. We categorize the complicated issues of digital system probabilistic risk assessment (PRA) into four groups based on their characteristics: hardware module issues, software issues, system issues, and safety function issues. Quantification of the effect of these issues dominates the quality of a developed risk model. Recent research activities for addressing various issues, such as the modeling framework of a software-based system, the software failure probability and the fault coverage of a self monitoring mechanism, are discussed. Although these issues are interrelated and affect each other, the categorized and systematic approach suggested here will provide a proper insight for analyzing risk from a digital system

  11. Analysis of parameter uncertainties in the assessment of seismic risk for nuclear power plants

    International Nuclear Information System (INIS)

    Yucemen, S.M.

    1981-04-01

    Probabilistic and statistical methods are used to develop a procedure by which the seismic risk at a specific site can be systematically analyzed. The proposed probabilistic procedure provides a consisted method for the modelling, analysis and updating of uncertainties that are involved in the seismic risk analysis for nuclear power plants. Methods are proposed for including these uncertainties in the final value of calculated risks. Two specific case studies are presented in detail to illustrate the application of the probabilistic method of seismic risk evaluation and to investigate the sensitivity of results to different assumptions

  12. Probabilistic safety assessments of nuclear power plants for low power and shutdown modes

    International Nuclear Information System (INIS)

    2000-03-01

    Within the past several years the results of nuclear power plant operating experience and performance of probabilistic safety assessments (PSAs) for low power and shutdown operating modes have revealed that the risk from operating modes other than full power may contribute significantly to the overall risk from plant operations. These early results have led to an increased focus on safety during low power and shutdown operating modes and to an increased interest of many plant operators in performing shutdown and low power PSAs. This publication was developed to provide guidance and insights on the performance of PSA for shutdown and low power operating modes. The preparation of this publication was initiated in 1994. Two technical consultants meetings were conducted in 1994 and one in February 1999 in support of the development of this report

  13. Framework for ensuring appropriate maintenance of baseline PSA and risk monitor models in a nuclear power plant

    International Nuclear Information System (INIS)

    Vrbanic, I.; Sorman, J.

    2005-01-01

    The necessity of observing both long term and short term risk changes many times imposes the need for a nuclear power plant to have a baseline PSA model to produce an estimate of long term averaged risk and a risk monitor to produce a time-dependent risk curve and/or safety functions status at points in time or over a shorter time period of interest. By nature, a baseline PSA reflects plant systems and operation in terms of average conditions and provides time-invariant quantitative risk metrics. Risk monitor, on the other hand, requires condition-specific modeling to produce a quantitative and/or qualitative estimate of plant's condition-specific risk metrics. While risk monitor is used for computing condition-specific risk metrics over time, a baseline PSA model is needed for variety of other risk oriented applications, such as assessments of proposed design modifications or risk ranking of equipment. Having in mind their importance and roles, it is essential that both models, i.e. baseline PSA model and risk monitor are maintained in the way that they represent, as accurately as practically achievable, the actual plant status (e.g. systems' design and plant's procedures in effect) and its history (e.g. numbers of equipment failures and demands that influence relevant PSA parameters). Paper discusses the requirements for appropriate maintenance of plant's baseline PSA model and risk monitor model and presents the framework for plant's engineering and administrative procedures that would ensure they are met. (author)

  14. Comprehensive Health Risk Management after the Fukushima Nuclear Power Plant Accident.

    Science.gov (United States)

    Yamashita, S

    2016-04-01

    Five years have passed since the Great East Japan Earthquake and the subsequent Fukushima Daiichi Nuclear Power Plant accident on 11 March 2011. Countermeasures aimed at human protection during the emergency period, including evacuation, sheltering and control of the food chain were implemented in a timely manner by the Japanese Government. However, there is an apparent need for improvement, especially in the areas of nuclear safety and protection, and also in the management of radiation health risk during and even after the accident. Continuous monitoring and characterisation of the levels of radioactivity in the environment and foods in Fukushima are now essential for obtaining informed consent to the decisions on living in the radio-contaminated areas and also on returning back to the evacuated areas once re-entry is allowed; it is also important to carry out a realistic assessment of the radiation doses on the basis of measurements. Until now, various types of radiation health risk management projects and research have been implemented in Fukushima, among which the Fukushima Health Management Survey is the largest health monitoring project. It includes the Basic Survey for the estimation of external radiation doses received during the first 4 months after the accident and four detailed surveys: thyroid ultrasound examination, comprehensive health check-up, mental health and lifestyle survey, and survey on pregnant women and nursing mothers, with the aim to prospectively take care of the health of all the residents of Fukushima Prefecture for a long time. In particular, among evacuees of the Fukushima Nuclear Power Plant accident, concern about radiation risk is associated with psychological stresses. Here, ongoing health risk management will be reviewed, focusing on the difficult challenge of post-disaster recovery and resilience in Fukushima. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  15. Risk management and nuclear human resources management in construction nuclear power plants in the Gulf Countries

    International Nuclear Information System (INIS)

    Saeed Hakami; Salim Almarmary

    2009-01-01

    The countries of the Gulf region have the capacity to rapidly expand their economic growth and gross domestic product (GDP). Also, one may observe that their growth rate is very high. To match this, they need a mix of energy sources for this economic growth. Nuclear power plants can have a significant role as a source of energy in the Gulf countries. Although, some of the Gulf countries signed contracts to construct nuclear power plants, they still require high a level of education as well as sufficient and adequate human resources in order to solve complex issues which may happen at nuclear power plants. The objective of this paper is to identify the complex issues that may arise at a nuclear site. Then the paper goes on to discuss how to evaluate these issues. Finally, the paper studies how to manage and control such complex issues in the work place. The advantage of highly educated people as well as sufficient and adequate human resource can increasingly protect and save human health and the natural environment from issues relating to the use of nuclear energy. There are vast theories, strategies and tools that have discussed in regards to human resources management in the nuclear industries. However, this paper chiefly provides a new risk management methodology. This methodology helps to highlight the risk factors and their consequences at nuclear sites. This paper is intended to decrease risks; to protect human health in the work place at nuclear power plants and save the environment within and beyond national borders and for future generations. It aims to increase safety from the use of nuclear energy, particularly in the Gulf countries.(Author)

  16. Reactor safety study. An assessment of accident risks in U.S. commercial nuclear power plants. Executive summary: main report

    International Nuclear Information System (INIS)

    1975-10-01

    Information is presented concerning the objectives and organization of the reactor safety study; the basic concepts of risk; the nature of nuclear power plant accidents; risk assessment methodology; reactor accident risk; and comparison of nuclear risks to other societal risks

  17. Health risk in nuclear power plants

    International Nuclear Information System (INIS)

    Bliznakov, V.

    1997-01-01

    Worked out are the health risk indices for NPP personnel that could be used in normal operation and in case of accident. These indices concern temporary incapacity for work, invalidity, lethality, cancer, etc. Risk estimation is based on produced energy in NPP or on the collective dose of personnel exposure. Assessed are the specific risk values for NPP ''Kozloduy'', which show that the risk in normal operation is significantly low (of the order of 2.3 ./. 7.2 x 10 -4 for invalidity, lethality and cancer). Health risk indices can be used when comparing various alternative energy sources, as well as for determination of the power strategy of a country. (author)

  18. Assessment of ISLOCA risk: Methodology and application to a Babcock and Wilcox nuclear power plant

    International Nuclear Information System (INIS)

    Galyean, W.J.; Gertman, D.I.

    1992-04-01

    This report presents information essential to understanding the risk associated with inter-system loss-of-coolant accidents (ISLOCAs). The methodology developed and presented in the report provides a state-of-the-art method for identifying and evaluating plant-specific hardware design, human performance issues, and accident consequence factors to relevant to the prediction of the ISLOCA risk. This ISLOCA methodology was developed and then applied to a Babcock and Wilcox (B ampersand W) nuclear power plants. The results from this application are described in detail. For this particular B ampersand W reference plant, the assessment indicated that the probability of a severe ISLOCA is approximately 2.2E-06/reactor-year. This document Volume 3 provides appendices A--H of the report. Topics are: Historical experience related to ISLOCA events; component failure rates; reference B ampersand W plant system descriptions; reference B ampersand W plant ISLOCA event trees; Human reliability analysis for the B ampersand W ISLOCA probabilistic risk assessment; thermal hydraulic calculations; bounding core uncovery time calculations; and system rupture probability

  19. ASME development of risk-based inspection guidelines for nuclear power plants

    International Nuclear Information System (INIS)

    Gore, B.F.; Balkey, K.R.

    1992-08-01

    A methodology has been developed for use in preparing guidelines for the in-service inspection of nuclear power plant pressure boundary and structural components. This methodology is a further development of a general methodology previously published by the task force for application to any industry. It is unique in that it utilizes probabilistic risk assessment (PRA) information to improve the quantification of risks associated with component ruptures. A procedure has also been recommended for using the resulting quantified risk estimates to determine target component rupture probability values to be maintained by inspection activities. Characteristics which an inspection strategy must possess in order to maintain target rupture probabilities are being determined by structural risk and reliability analysis (SRRA) calculations. The major features of this methodology are described in this paper, and example applications are briefly discussed. Plans for additional work in developing and applying the methodology are described

  20. Analytic advanced development in the German Risk Study on Nuclear Power Plants

    International Nuclear Information System (INIS)

    1984-01-01

    The study carried out by the Ecological Institute (Oeko-Institut) deals with the difficulties encountered with the decision-making models and statistical models and methods of the German Risk Study on Nuclear Power Plants for the determination of care meltdown frequency and for the estimation of the behaviour of components in the event of a failure. Related deficiencies of the German Risk Study and the absence of completeness and lading representiveness of the course and causes of incidents considered are pointed out. The accident consequences model and the climatological-meteorological data base are considered non-representative. (RF) [de

  1. Safety goals for nuclear power plant operation

    International Nuclear Information System (INIS)

    1983-05-01

    This report presents and discusses the Nuclear Regulatory Commission's, Policy Statement on Safety Goals for the Operation of Nuclear Power Plants. The safety goals have been formulated in terms of qualitative goals and quantitative design objectives. The qualitative goals state that the risk to any individual member of the public from nuclear power plant operation should not be a significant contributor to that individual's risk of accidental death or injury and that the societal risks should be comparable to or less than those of viable competing technologies. The quantitative design objectives state that the average risks to individual and the societal risks of nuclear power plant operation should not exceed 0.1% of certain other risks to which members of the US population are exposed. A subsidiary quantitative design objective is established for the frequency of large-scale core melt. The significance of the goals and objectives, their bases and rationale, and the plan to evaluate the goals are provided. In addition, public comments on the 1982 proposed policy statement and responses to a series of questions that accompanied the 1982 statement are summarized

  2. Comparative Health Risk Assessment of CdTe Solar PV System and Nuclear Power Plant

    International Nuclear Information System (INIS)

    Lee, Sang Hun; Kang, Hyun Gook

    2014-01-01

    In terms of national energy policy decision-making process, several key factors, including low production cost, negligible risk or impact to environment and population around the facility, must be considered. The purpose of this paper is to assess the public health risk in case of postulated nuclear power plant and CdTe solar PV system accident and compare the estimated public health risk. Both systems release toxic materials to the environment which adversely affect nearby population by exposure from the inhalation and ingestion of the toxic material transported via air. By simulating the airborne transport of released toxic material using Gaussian plume model and modeling exposure pathways to nearby population, average individual health risk is assessed and public health risk per power capacity of each system is compared. The result shows that the average public health risk per power capacity of NPP is less than the case of solar PV system. This implies that NPP has lower risk in terms of public health risk in case of severe accident while it can be used as more reliable energy source than renewable energy source so that NPP would take priority over other renewable energy sources in terms of national energy policy

  3. Forum for fire protection and safety in power plants[Norway

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    The conference contains 16 presentations on topics in the fields of fire protection and safety in plants in Western Norway, reorganization and reconstruction of power systems and plants in Norway, various aspects of risk and vulnerability analysis, technological aspects of plant management and construction and problems and risks with particularly transformers. Some views on challenges of the fire departments and the new Norwegian regulations for electrical power supply systems are included. One presentation deals with challenges for Icelandic power production plants.

  4. Advanced digital I ampersand C systems in nuclear power plants: Risk- sensitivities to environmental stressors

    International Nuclear Information System (INIS)

    Hassan, M.; Vesely, W.E.

    1996-01-01

    Microprocessor-based advanced digital systems are being used for upgrading analog instrumentation and control (I ampersand C) systems in nuclear power plants (NPPs) in the United States. A concern with using such advanced systems for safety-related applications in NPPs is the limited experience with this equipment in these environments. In this study, we investigate the risk effects of environmental stressors by quantifying the plant's risk-sensitivities to them. The risk- sensitivities are changes in plant risk caused by the stressors, and are quantified by estimating their effects on I ampersand C failure occurrences and the consequent increase in risk in terms of core damage frequency (CDF). We used available data, including military and NPP operating experience, on the effects of environmental stressors on the reliability of digital I ampersand C equipment. The methods developed are applied to determine and compare risk-sensitivities to temperature, humidity, vibration, EMI (electromagnetic interference) from lightning and smoke as stressors in an example plant using a PRA (Probabilistic Risk Assessment). Uncertainties in the estimates of the stressor effects on the equipment's reliability are expressed in terms of ranges for risk-sensitivities. The results show that environmental stressors potentially can cause a significant increase in I ampersand C contributions to the CDF. Further, considerable variations can be expected in some stressor effects, depending on where the equipment is located

  5. The financing of nuclear power plants

    International Nuclear Information System (INIS)

    2009-01-01

    Many countries have recognised that greater use of nuclear power could play a valuable role in reducing carbon dioxide emissions. However, given the high capital cost and complexity of nuclear power plants, financing their construction often remains a challenge. This is especially true where such financing is left to the private sector in the context of competitive electricity markets. This study examines the financial risks involved in investing in a new nuclear power plant, how these can be mitigated, and how projects can be structured so that residual risks are taken by those best able to manage them. Given that expansion of nuclear power programmes will require strong and sustained government support, the study highlights the role of governments in facilitating and encouraging investment in new nuclear generating capacity

  6. A quantitative and comparative evaluation of the risks from nuclear power plants

    International Nuclear Information System (INIS)

    Vignes, S.; Bertin, M.; Nenot, J.C.

    1980-01-01

    All the significant data for the assessment of risks from the operation of nuclear power plants was collected and these risks were compared with all the risks of modern life. The scientific bases for the evaluation of individual risks and detriment were defined by UNSCEAR (1977) and by ICRP 26 (1978). In different industries, the risk of death from long term occupational illness is about 130 to 14,000 per million workers. For accidental deaths, the risk is estimated at about 16 to 1,600. The risk for the nuclear industry is lower than 100 per million workers. Comparisons are made with different causes of lethality: deaths from atmospheric pollution (sulfur compounds and dusts) related to fossile fuel combustion; iatrogenic accidents attributed to some drugs used in medicine or to other kind of treatment; calculated mortality for workers exposed to asestosis. The nuclear industr of the safest. The only risk to be considered is the major accident, the probability of which is very low. (H.K.)

  7. Risk informed life cycle plant design

    International Nuclear Information System (INIS)

    Hill, Ralph S. III; Nutt, Mark M.

    2003-01-01

    Many facility life cycle activities including design, construction, fabrication, inspection and maintenance are evolving from a deterministic to a risk-informed basis. The risk informed approach uses probabilistic methods to evaluate the contribution of individual system components to total system performance. Total system performance considers both safety and cost considerations including system failure, reliability, and availability. By necessity, a risk-informed approach considers both the component's life cycle and the life cycle of the system. In the nuclear industry, risk-informed approaches, namely probabilistic risk assessment (PRA) or probabilistic safety assessment (PSA), have become a standard tool used to evaluate the safety of nuclear power plants. Recent studies pertaining to advanced reactor development have indicated that these new power plants must provide enhanced safety over existing nuclear facilities and be cost-competitive with other energy sources. Risk-informed approaches, beyond traditional PRA, offer the opportunity to optimize design while considering the total life cycle of the plant in order to realize these goals. The use of risk-informed design approaches in the nuclear industry is only beginning, with recent promulgation of risk-informed regulations and proposals for risk-informed codes. This paper briefly summarizes the current state of affairs regarding the use of risk-informed approaches in design. Key points to fully realize the benefit of applying a risk-informed approach to nuclear power plant design are then presented. These points are equally applicable to non-nuclear facilities where optimization for cost competitiveness and/or safety is desired. (author)

  8. Next Generation Geothermal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Brugman, John; Hattar, Mai; Nichols, Kenneth; Esaki, Yuri

    1995-09-01

    A number of current and prospective power plant concepts were investigated to evaluate their potential to serve as the basis of the next generation geothermal power plant (NGGPP). The NGGPP has been envisaged as a power plant that would be more cost competitive (than current geothermal power plants) with fossil fuel power plants, would efficiently use resources and mitigate the risk of reservoir under-performance, and minimize or eliminate emission of pollutants and consumption of surface and ground water. Power plant concepts were analyzed using resource characteristics at ten different geothermal sites located in the western United States. Concepts were developed into viable power plant processes, capital costs were estimated and levelized busbar costs determined. Thus, the study results should be considered as useful indicators of the commercial viability of the various power plants concepts that were investigated. Broadly, the different power plant concepts that were analyzed in this study fall into the following categories: commercial binary and flash plants, advanced binary plants, advanced flash plants, flash/binary hybrid plants, and fossil/geothed hybrid plants. Commercial binary plants were evaluated using commercial isobutane as a working fluid; both air-cooling and water-cooling were considered. Advanced binary concepts included cycles using synchronous turbine-generators, cycles with metastable expansion, and cycles utilizing mixtures as working fluids. Dual flash steam plants were used as the model for the commercial flash cycle. The following advanced flash concepts were examined: dual flash with rotary separator turbine, dual flash with steam reheater, dual flash with hot water turbine, and subatmospheric flash. Both dual flash and binary cycles were combined with other cycles to develop a number of hybrid cycles: dual flash binary bottoming cycle, dual flash backpressure turbine binary cycle, dual flash gas turbine cycle, and binary gas turbine

  9. Layout of nuclear power plants against external hazards

    International Nuclear Information System (INIS)

    Suetterlin, L.

    1975-03-01

    The present paper has the purpose to show the risk of operating a nuclear power plant that is not protected against an airplane crash. At first, considerations of probabilities are made and numerical data for various categories of air traffic are given. A general consideration of the possible extent of damage after an airplane impact upon an unprotected nuclear power plant is followed by a discussion of the risk philosophy which is based upon the Farmer-diagrams. Furthermore the facts are specified which led to the decision that nuclear power plants in the Federal Republic of Germany must be protected against an airplane crash. (orig.) [de

  10. Measuring risk in a Philippine power plant: the Philippine experience in transfer of technology

    International Nuclear Information System (INIS)

    Savellano, R.A.; Leon, G.C. de; Azanon, E.M.

    1989-01-01

    The Philippine experience in risk assessment and management is more pronounced in the field of energy systems. This particular study focuses on the evaluation and management of pollutant emission from a geothermal power plant. It embraces two main methodologies 1) the systematic calculation of the risks impacts of the energy systems to human health and to the environment, and 2) the evaluation of cost-effectiveness of risk reduction schemes. Presented in detail is how the researchers resolve the problems and the approach perceived as necessary for an effective risk management. (ELC). 12 refs.; 5 tabs.; 3 figs

  11. POTENTIAL HEALTH RISK REDUCTION ARISING FROM REDUCED MERCURY EMISSIONS FROM COAL FIRED POWER PLANTS.

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, T. M.; Lipfert, F. W.; Morris, S. C.; Moskowitz, P. D.

    2001-09-01

    The U.S. Environmental Protection Agency (EPA) has announced plans to regulate mercury (Hg) emissions from coal-fired power plants. EPA has not prepared a quantitative assessment of the reduction in risk that could be achieved through reduction in coal plant emissions of Hg. To address this issue, Brookhaven National Laboratory (BNL) with support from the U.S. Department of Energy Office of Fossil Energy (DOE FE) prepared a quantitative assessment of the reduction in human health risk that could be achieved through reduction in coal plant emissions of Hg. The primary pathway for Hg exposure is through consumption of fish. The most susceptible population to Hg exposure is the fetus. Therefore the risk assessment focused on consumption of fish by women of child-bearing age. Dose response factors were generated from studies on loss of cognitive abilities (language skills, motor skills, etc.) by young children whose mothers consumed large amounts of fish with high Hg levels. Population risks were estimated for the general population in three regions of the country, (the Midwest, Northeast, and Southeast) that were identified by EPA as being heavily impacted by coal emissions. Three scenarios for reducing Hg emissions from coal plants were considered: (1) A base case using current conditions; (2) A 50% reduction; and, (3) A 90% reduction. These reductions in emissions were assumed to translate linearly into a reduction in fish Hg levels of 8.6% and 15.5%, respectively. Population risk estimates were also calculated for two subsistence fisher populations. These groups of people consume substantially more fish than the general public and, depending on location, the fish may contain higher Hg levels than average. Risk estimates for these groups were calculated for the three Hg levels used for the general population analyses. Analysis shows that the general population risks for exposure of the fetus to Hg are small. Estimated risks under current conditions (i.e., no

  12. Application of fire models for risk analysis in french nuclear power plants

    International Nuclear Information System (INIS)

    Brauns, P.

    1989-04-01

    Numerical simulations of compartment fires have been carried out in the French 900 MW and 1 300 MW nuclear power plants, to obtain quantitative data about this particular kind of risk: characteristic spreading times from one redundant electrical train to the other one, behaviour of important electrical components... The main stages of both studies were the following: selection of rooms, the location or function of which are essential for the plant safety in case of fire, on-site inspections to collect information about these rooms (amount of fuel, openings...), definition of fire scenarios, improvement of the fire model VESTA-PLUS, and, finally calculations using this computer code. The simulations have shown two major trends: i) the spreading times, without taking into account any external intervention, are always greater than half an hour, and ii) the specific design of the 1 300 MW power plants generally prevents one of the redundant train from being damaged due to a fire occurring in a room containing the other one. Examples of typical results obtained are given, showing the capability of application of the improved fire model to complex problems

  13. Status of ASME risk-based inspection guidelines development for nuclear power plants

    International Nuclear Information System (INIS)

    Gore, B.F.; Vo, T.V.; Balkey, K.R.

    1991-01-01

    The general methodology published by the task force is being applied to develop guidelines for the inspection of nuclear power plant components. The methodology has been expanded to include the use of information from probabilistic risk assessments to improve the quantification of risks associated with component ruptures. In addition, a procedure has been recommended for using these quantified risk estimates to determine target component rupture probability values to be maintained by inspection activities. Finally, the method for determining the characteristics which an inspection strategy must possess in order to maintain these target rupture probabilities has been described. This paper presents the major features of this methodology, along with a discussion of the status of efforts to develop and to apply it further

  14. Seismic reevaluation of existing nuclear power plants

    International Nuclear Information System (INIS)

    Hennart, J.C.

    1978-01-01

    The codes and regulations governing Nuclear Power Plant seismic analysis are continuously becoming more stringent. In addition, design ground accelerations of existing plants must sometimes be increased as a result of discovery of faulting zones or recording of recent earthquakes near the plant location after plant design. These new factors can result in augmented seismic design criteria. Seismic reanalysius of the existing Nuclear Power Plant structures and equipments is necessary to prevent the consequences of newly postulated accidents that could cause undue risk to the health or safety of the public. This paper reviews the developments of seismic analysis as applied to Nuclear Power Plants and the methods used by Westinghouse to requalify existing plants to the most recent safety requirements. (author)

  15. Critique of the RASMUSSEN report (WASH-1400) on accident risks in U.S. commercial nuclear power plants

    International Nuclear Information System (INIS)

    Krueger, F.W.

    1976-06-01

    The RASMUSSEN study represents an excellent survey of the current possibilities to assess quantitatively the operational risk of nuclear power plants. To close the big gaps which turned out to be still existent in calculating the possible accidents sequences and their consequences but also in the statistical materials, only rough models could be used because of the limited capability of theoretical analyses to replace lacking experience. Contrary to previous studies the risk estimates have not deliberately been maximized, apart from the fact that in many cases no 'safe' side does a priori exist. Rather, the RASMUSSEN study tried to make 'reasonable realistic' assumptions concerning accident sequences and activity release consequences, but it is difficult to refute that the results will tend to underestimate systematically the accident consequences. Besides, in every case the range of uncertainty will very likely be greater than stated in the study, not least also because the results are substantially influenced by technical features of the nuclear power plants under discussion. This should be given attention in discussions using the quantitative results of the study as well as the fact that planning, construction and operation of nuclear power plants must be done with utmost accuracy to achieve the specified low orders of risk. (author)

  16. RIBA Project - Risk-Informed approach for In-Service Inspection of Nuclear Power Plant Components. Project summary

    International Nuclear Information System (INIS)

    Lidbury, D.; Smith, G.

    2001-12-01

    The need for a European review of a Risk-Informed Approach for In-Service Inspection of Nuclear Power Plant Components (RIBA) was identified in 1998. This was as a priority item in the programme of activities conducted in the framework of the Council Resolutions of 22 July 1975 and of 18 June 1992 on the Technological Problems of Nuclear Safety. The RIBA Project was established in November 1999 as a 24-month Study Contract funded by the European Commission within the frame of the former DG XI WGCS (Working Group on Codes and Standards). The Study Contract was subsequently managed for the EC by DG TREN. The participants in RIBA were Serco Assurance (project coordinator), Ringhals AB, EDF, Tecnatom SA and Westinghouse Electric Europe. The work is presented in a summary report with the detailed results contained in three companion reports as follows: main conclusions and recommendations, Review of Existing Risk-Informed Methodologies, A Comparative Study of Risk-Informed In-Service Inspection Applications, Conclusions and Recommendations for Risk-Informed in-service inspection methodology applied to Nuclear Power Plants in Europe. (author)

  17. A framework of risk-informed seismic safety evaluation of nuclear power plants in Japan

    International Nuclear Information System (INIS)

    Kondo, S.; Sakagami, M.; Hirano, M.; Shiba, M.

    2001-01-01

    A framework of risk-informed seismic design and safety evaluation of nuclear power plants is under consideration in Japan so as to utilize the progress in the seismic probabilistic safety assessment methodology. Issues resolved to introduce this framework are discussed after the concept, evaluation process and characteristics of the framework are described. (author)

  18. A risk-based review of Instrument Air systems at nuclear power plants

    International Nuclear Information System (INIS)

    DeMoss, G.; Lofgren, E.; Rothleder, B.; Villeran, M.; Ruger, C.

    1990-01-01

    The broad objective of this analysis was to provide risk-based information to help focus regulatory actions related to Instrument Air (IA) systems at operating nuclear power plants. We first created an extensive data base of summarized and characterized IA-related events that gave a qualitative indication of the nature and severity of these events. Additionally, this data base was used to calculate the frequencies of certain events, which were used in the risk analysis. The risk analysis consisted of reviewing published PRAs and NRC Accident Sequence Precursor reports for IA-initiated accident sequences, IA interactions with frontline systems, and IA-related risk significant events. Sensitivity calculations were performed when possible. Generically, IA was found to contribute less to total risk than many safety systems; however, specific design weaknesses in safety systems, non-safety systems, and the IA system were found to be significant in risk. 22 refs., 13 figs., 24 tabs

  19. Plant risk status information management system

    International Nuclear Information System (INIS)

    Campbell, D.J.; Ellison, B.C.; Glynn, J.C.; Flanagan, G.F.

    1985-01-01

    The Plant Risk Status Information Management System (PRISIMS) is a PC program that presents information about a nuclear power plant's design, its operation, its technical specifications, and the results of the plant's probabilistic risk assessment (PRA) in a logically and easily accessible format. PRISIMS provides its user with unique information for integrating safety concerns into day-to-day operational decisions and/or long-range management planning

  20. Nuclear power plants and prevention of sanitary risks

    International Nuclear Information System (INIS)

    Delpla, M.

    1977-01-01

    The radioprotection specialists know that people irradiation can cause fearful diseases even to their descendance. So they wanted to predict the upper limit of the damage that could be caused by irradiations at the limits of radioprotection doses of IRCP standards recommended for the whole population. For their previsional calculations, they admitted the proportionality between the most fearful risks and the accumulated individual dose, whatever the time is. According to such an hypothesis, the previsional damage would be proportional to the population dose. Observed damages on accidentally or experimentally irradiated population will be compared to the previsional damage, calculated from the values generally admitted for the risks. The author will consider the risks which are usually taken in account in the protection of people against the hazard of nuclear power plants such as: leukemia, thyroid cancer. Such comparisons will allow to propose, in the field of radioprotection: to abandon the hypothesis of proportionality between the risk and the dose; to admit a practical threshold dose for each of the most fearful effects; to admit the same radiation protection standards for eveyone; to try to interpret facts until then unnoticed, or when they have been seen, called 'paradoxical'; these facts may be due to the stimulating effect of a suitable dose of ionizing radiation. Such a stimulating effect is well known by the radiologists, but some of the latter are afraid of secondary delate effects. This new field of research may be as useful to radiotherapy as to radioprotection [fr

  1. A probabilistic seismic risk assessment procedure for nuclear power plants: (II) Application

    Science.gov (United States)

    Huang, Y.-N.; Whittaker, A.S.; Luco, N.

    2011-01-01

    This paper presents the procedures and results of intensity- and time-based seismic risk assessments of a sample nuclear power plant (NPP) to demonstrate the risk-assessment methodology proposed in its companion paper. The intensity-based assessments include three sets of sensitivity studies to identify the impact of the following factors on the seismic vulnerability of the sample NPP, namely: (1) the description of fragility curves for primary and secondary components of NPPs, (2) the number of simulations of NPP response required for risk assessment, and (3) the correlation in responses between NPP components. The time-based assessment is performed as a series of intensity-based assessments. The studies illustrate the utility of the response-based fragility curves and the inclusion of the correlation in the responses of NPP components directly in the risk computation. ?? 2011 Published by Elsevier B.V.

  2. Assessment of risks of accidents and normal operation at nuclear power plants

    International Nuclear Information System (INIS)

    Savolainen, Ilkka; Vuori, Seppo.

    1977-01-01

    A probabilistic assessment model for the analysis of risks involved in the operation of nuclear power plants is described. With the computer code ARANO it is possible to estimate the health and economic consequences of reactor accidents both in probabilistic and deterministic sense. In addition the code is applicable to the calculation of individual and collective doses caused by the releases during normal operation. The estimation of release probabilities and magnitudes is not included in the model. (author)

  3. Update on the EPRI power generation risk-based inservice inspection pilot plant studies

    International Nuclear Information System (INIS)

    Gosselin, S.R.

    1997-01-01

    The scope for ASME Section XI ISI programs is largely based on deterministic results contained in design stress reports. These reports are normally very conservative and may not be an accurate representation of failure potential. Service experience has shown that failures are due to either corrosion or fatigue and typically occur in areas not included in the plant's ISI program. Consequently, nuclear plants are devoting significant resources to inspection programs that provide minimum benefit. As an alternative, significant industry attention has been devoted to the application of risked-based selection criteria in order to determine the scope of inservice inspection (ISI) programs at nuclear power plants. Preliminary EPRI studies indicate that the application of these techniques will allow operating nuclear plants to reduce the examination scope of current ISI programs by as much as 60 to 80%, significantly reduce costs, and continue to maintain high nuclear plant safety standards

  4. A completely new design and regulatory process - A risk-based approach for new nuclear power plants. Annex 17

    International Nuclear Information System (INIS)

    Ritterbusch, S.E.

    2002-01-01

    In the de-regulated electric power market place that is developing in the USA, competition from alternative electric power sources has provided significant downward pressure on the costs of new construction projects. Studies by the Electric Power Research Institute have shown that, in the USA, the capital cost of new nuclear plants must be decreased by at least 35% to 40% relative to the cost of Advanced Light Water Reactors designed in the early 1990s in order to be competitive with capital costs of gas-fired electric power plants. The underlying reasons for the high capital costs estimated for some nuclear plants are (1) long construction times, (2) the high level of 'defense-in-depth' or safety margin, included throughout the design and licensing process, and (3) the use of out-dated design methods and information. Probabilistic Safety Assessments are being used to develop a more accurate assessment of real plant risk and to provide relief if it can be demonstrated that plant equipment is not providing a significant contribution to plant safety. Westinghouse addressed some of these cost drivers in the development of the AP-600 passive plant design. However, because of relatively inexpensive natural gas plant alternative, we need to reduce the costs even further. Therefore, the AP-600 design is now being up-rated to a 1000 MWe design, AP-1000. The development of AP1000 is described in another paper being presented at this meeting. Westinghouse is also managing a project, sponsored by the US Department of Energy, which is aimed at developing an all-new 'risk-based' approach to design and regulation. Methodologies being developed use risk-based information to the extent practical and 'defense-in-depth' only when necessary to address uncertainties in models and equipment performance. Early results, summarized in this paper, include (1) the initial framework for a new design and regulatory process and (2) a sample design analysis which shows that the Emergency Core

  5. Indoor Soiling Method and Outdoor Statistical Risk Analysis of Photovoltaic Power Plants

    Science.gov (United States)

    Rajasekar, Vidyashree

    This is a two-part thesis. Part 1 presents an approach for working towards the development of a standardized artificial soiling method for laminated photovoltaic (PV) cells or mini-modules. Construction of an artificial chamber to maintain controlled environmental conditions and components/chemicals used in artificial soil formulation is briefly explained. Both poly-Si mini-modules and a single cell mono-Si coupons were soiled and characterization tests such as I-V, reflectance and quantum efficiency (QE) were carried out on both soiled, and cleaned coupons. From the results obtained, poly-Si mini-modules proved to be a good measure of soil uniformity, as any non-uniformity present would not result in a smooth curve during I-V measurements. The challenges faced while executing reflectance and QE characterization tests on poly-Si due to smaller size cells was eliminated on the mono-Si coupons with large cells to obtain highly repeatable measurements. This study indicates that the reflectance measurements between 600-700 nm wavelengths can be used as a direct measure of soil density on the modules. Part 2 determines the most dominant failure modes of field aged PV modules using experimental data obtained in the field and statistical analysis, FMECA (Failure Mode, Effect, and Criticality Analysis). The failure and degradation modes of about 744 poly-Si glass/polymer frameless modules fielded for 18 years under the cold-dry climate of New York was evaluated. Defect chart, degradation rates (both string and module levels) and safety map were generated using the field measured data. A statistical reliability tool, FMECA that uses Risk Priority Number (RPN) is used to determine the dominant failure or degradation modes in the strings and modules by means of ranking and prioritizing the modes. This study on PV power plants considers all the failure and degradation modes from both safety and performance perspectives. The indoor and outdoor soiling studies were jointly

  6. Toxic releases from power plants

    International Nuclear Information System (INIS)

    Rubin, E.S.

    1999-01-01

    Beginning in 1998, electric power plants burning coal or oil must estimate and report their annual releases of toxic chemicals listed in the Toxics Release Inventory (TRI) published by the US Environmental Protection Agency (EPA). This paper identifies the toxic chemicals of greatest significance for the electric utility sector and develops quantitative estimates of the toxic releases reportable to the TRI for a representative coal-fired power plant. Key factors affecting the magnitude and types of toxic releases for individual power plants also are discussed. A national projection suggests that the magnitude of electric utility industry releases will surpass those of the manufacturing industries which current report to the TRI. Risk communication activities at the community level will be essential to interpret and provide context for the new TRI results

  7. Risk perception of workers at nuclear power plants from Angra dos Reis, Rio de Janeiro State: preliminary study of a reality on health

    International Nuclear Information System (INIS)

    Scliar, Claudio; Vasconcelos, Ana S.F.; Rodrigues, Anacely S.; Santos, Gloria R.R.; Albuquerque, Patricia O.; Carvalho, Sirlene L.A.; Oliveira, Simone

    1999-01-01

    The present paper analyses some social and occupational parameters that may have an influence on the risk perception levels of the workers in Brazilian Nuclear Power pLants, emphasizing possible relationship between the specificity of job tasks/literacy and risk perception. This study was based on two findings from the scientific literature: risk perception increases proportionally with literacy; risk perception decreases proportionally with the specificity of job tasks. The results of this pilot study indicates that risk perception levels of the workers in Brazilian Nuclear Power Plants increases proportionally with the literacy and specificity of their job tasks, contrasting with the american and european profiles. These results appears as a singular reality of those workers and the possibility of a new regard over the management and decision making process in the Brazilian Nuclear Power Plants. (author)

  8. Contribution to evaluating nuclear power plant accidents

    International Nuclear Information System (INIS)

    Razga, J.; Horacek, P.

    1990-01-01

    Large-scale accidents pose the highest risk in the use of nuclear power. They are the major factor that has to be taken into account when assessing the effect of nuclear power plants on human health and on the environment. In Czechoslovak conditions, the effectiveness of provisions made to reduce the hazard of large-scale nuclear power plant accidents must be considered from the following aspects: effect on human health, consequences of long-term disabling of the infrastructure, potential of human and material reserves in coping with the accident, consequences of power failure for the electricity system, effect on agricultural production and catering, risk of ground and surface water contamination in the Labe or Danube river basin, and international political aspects. (Z.M.). 3 tabs., 18 refs

  9. Nuclear power plants

    International Nuclear Information System (INIS)

    1985-01-01

    Data concerning the existing nuclear power plants in the world are presented. The data was retrieved from the SIEN (Nuclear and Energetic Information System) data bank. The information are organized in table forms as follows: nuclear plants, its status and type; installed nuclear power plants by country; nuclear power plants under construction by country; planned nuclear power plants by country; cancelled nuclear power plants by country; shut-down nuclear power plants by country. (E.G.) [pt

  10. Safety provision for nuclear power plants during remaining running time

    International Nuclear Information System (INIS)

    Rossnagel, Alexander; Hentschel, Anja

    2012-01-01

    With the phasing-out of the industrial use of nuclear energy for the power generation, the risk of the nuclear power plants has not been eliminated in principle, but only for a limited period of time. Therefore, the remaining nine nuclear power plants must also be used for the remaining ten years according to the state of science and technology. Regulatory authorities must substantiate the safety requirements for each nuclear power plant and enforce these requirements by means of various regulatory measures. The consequences of Fukushima must be included in the assessment of the safety level of nuclear power plants in Germany. In this respect, the regulatory authorities have the important tasks to investigate and assess the security risks as well as to develop instructions and orders.

  11. Source modelling in seismic risk analysis for nuclear power plants

    International Nuclear Information System (INIS)

    Yucemen, M.S.

    1978-12-01

    The proposed probabilistic procedure provides a consistent method for the modelling, analysis and updating of uncertainties that are involved in the seismic risk analysis for nuclear power plants. The potential earthquake activity zones are idealized as point, line or area sources. For these seismic source types, expressions to evaluate their contribution to seismic risk are derived, considering all the possible site-source configurations. The seismic risk at a site is found to depend not only on the inherent randomness of the earthquake occurrences with respect to magnitude, time and space, but also on the uncertainties associated with the predicted values of the seismic and geometric parameters, as well as the uncertainty in the attenuation model. The uncertainty due to the attenuation equation is incorporated into the analysis through the use of random correction factors. The influence of the uncertainty resulting from the insufficient information on the seismic parameters and source geometry is introduced into the analysis by computing a mean risk curve averaged over the various alternative assumptions on the parameters and source geometry. Seismic risk analysis is carried for the city of Denizli, which is located in the seismically most active zone of Turkey. The second analysis is for Akkuyu

  12. Probability analysis of nuclear power plant hazards

    International Nuclear Information System (INIS)

    Kovacs, Z.

    1985-01-01

    The probability analysis of risk is described used for quantifying the risk of complex technological systems, especially of nuclear power plants. Risk is defined as the product of the probability of the occurrence of a dangerous event and the significance of its consequences. The process of the analysis may be divided into the stage of power plant analysis to the point of release of harmful material into the environment (reliability analysis) and the stage of the analysis of the consequences of this release and the assessment of the risk. The sequence of operations is characterized in the individual stages. The tasks are listed which Czechoslovakia faces in the development of the probability analysis of risk, and the composition is recommended of the work team for coping with the task. (J.C.)

  13. Public perception on the benefits and risks of nuclear power plants. A simplified study

    International Nuclear Information System (INIS)

    Ribeiro Junior, Joaquim Apparecido

    2007-01-01

    Public acceptance of the nuclear based electricity generation depends on many variables that can be affected by circumstances and interests, which although seemingly not close to the issue, can strongly influence the final outcome. Explicit or consented positions assumed by opinion makers and some segments of society are subject to episodic waves of interaction through the media and they permeate to the public in a process that is very complex to be fully understood. The modeling of such process is a very complicated undertaking, and gives no assurance of practical results concerning to what, how and who, should be given prominence in the interactions with the media and the general public. In this context, the risk communication has assumed a leading role and, as a consequence, most of the interaction with the public has been done with both defensive language and content. This study has tried a simple and practical approach to the problem, in such a way as to gather some interesting subsidies to treat this issue in a different way. The basic assumption is that in a similar way as individuals base their decision to acquire a new good or service on a 'intuitive' cost-benefit judgment, society (as a collection of individuals) also manifest their acceptance (or not) with respect to industrial installations and undertakings by comparing risks and benefits according to their perception. An exploratory survey was carried out in a few high schools, colleges and MBA courses in the state of Sao Paulo, Brazil. A first part was aimed to catch and understand the public perception of: the intrinsic value of the electric energy, the need to universalize the access to electricity, nuclear plants, the acceptance deficit of nuclear power as compared to other sources of energy, the benefits a nuclear plant can bring and who does and who does not deserves credibility to speak about nuclear plants. The second part was addressed to grasp a picture of more relevant distortions concerned

  14. LNG plant combined with power plant

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, I; Kikkawa, Y [Chiyoda Chemical Engineering and Construction Co. Ltd., Tokyo (Japan)

    1997-06-01

    The LNG plant consumers a lot of power of natural gas cooling and liquefaction. In some LNG plant location, a rapid growth of electric power demand is expected due to the modernization of area and/or the country. The electric power demand will have a peak in day time and low consumption in night time, while the power demand of the LNG plant is almost constant due to its nature. Combining the LNG plant with power plant will contribute an improvement the thermal efficiency of the power plant by keeping higher average load of the power plant, which will lead to a reduction of electrical power generation cost. The sweet fuel gas to the power plant can be extracted from the LNG plant, which will be favorable from view point of clean air of the area. (Author). 5 figs.

  15. LNG plant combined with power plant

    International Nuclear Information System (INIS)

    Aoki, I.; Kikkawa, Y.

    1997-01-01

    The LNG plant consumers a lot of power of natural gas cooling and liquefaction. In some LNG plant location, a rapid growth of electric power demand is expected due to the modernization of area and/or the country. The electric power demand will have a peak in day time and low consumption in night time, while the power demand of the LNG plant is almost constant due to its nature. Combining the LNG plant with power plant will contribute an improvement the thermal efficiency of the power plant by keeping higher average load of the power plant, which will lead to a reduction of electrical power generation cost. The sweet fuel gas to the power plant can be extracted from the LNG plant, which will be favorable from view point of clean air of the area. (Author). 5 figs

  16. German study on the risks of nuclear power plants

    International Nuclear Information System (INIS)

    Wollny, V.

    1987-01-01

    The 'Deutsche Risikostudie Kernkraftwerke', DRS, (German study on the risks of nuclear plants) calculates a frequency of 1/10000 years (i.e. once in 10000 years of reactor operation) for the event of insufficient cooling of the reactor core occurring. The resulting collective risk is put at approximately 10 deaths per year for 25 plants. As the explanations show, the error margin of such a risk statement is enormous. Moreover, much seems to indicate that the risk was underrated. Apart from this, risk analyses are of doubtful value in the decision process for or against the introduction of large-scale technologies. They cannot replace the individual decision of all concerned. (orig./HSCH) [de

  17. Quantitative evaluation of the impact of human reliability in risk assessment for nuclear power plants

    International Nuclear Information System (INIS)

    Samanta, P.K.

    1981-01-01

    The role of human beings in the safe operation of a nuclear power plant has been a matter of concern. This study describes methods for the quantitative description of that role and its impact on the risk from nuclear power plants. The impact of human errors was calculated by observing the changes in risk parameters, such as core melt probability, release category probabilities, accident sequence probabilities and system unavailabilities due to changes in the contribution to unavailablity of human errors, within the framework of risk assessment methodology. It was found that for operational pressurized water reactors the opportunity for reduction in core melt probability by reducing the human error rates without simultaneous reduction of hardware failures is limited, but that core melt probability would significantly increase as human error rates increased. More importantly, most of the dominant accident sequences showed a significant increase in their probabilities with an increase in human error rates. Release categories resulting in high consequences showed a much larger sensitivity to human errors than categories resulting in low consequences. A combination of structural importance and reliability importance measure was used to describe the importance of individual errors

  18. Information needs in nuclear power plants during low power operation modes

    Energy Technology Data Exchange (ETDEWEB)

    Tommila, Teemu; Fantoni, Paolo F.; Zander, Ralf M.

    1998-02-01

    During the past few years an increasing attention has been paid to the safety of shutdown and refuelling operations. It has turned out that the risks during shutdown may be comparable to the risks of power operation. The goal of this report is to identify information requirements related to low power operating modes of nuclear power plants. These include, for example, warm and cold shutdowns, refuelling and maintenance, as well as related state transitions such as start-up and shut-down. The focus of the report is on planned refuelling outages and the role of the control room in managing the outage activities. As a starting point, the basic terminology and characteristics of low power operation are discussed. The current situation at nuclear power plants and some recent developments in information technology are reviewed. End-users' requirements and enabling technologies are combined in order to identify the opportunities for new information technology tools in low power operation. The required features of process control systems and maintenance information systems are described. Common plant modelling techniques, open software architectures and functional structuring of the process control system are suggested to be the key issues in the long-term development of operator support systems. On a shorter time scale, new tools solving limited practical problems should be developed and evaluated. This would provide a basis for the features needed for low power operation, including for example, outage planning, on-line risk monitoring, management of outage tasks, adaptive alarm handling, computerised procedures and task-oriented human interfaces. (author)

  19. Development of fragility descriptions of equipment for seismic risk assessment of nuclear power plants

    International Nuclear Information System (INIS)

    Hardy, G.S.; Campbell, R.D.

    1983-01-01

    Probabilistic risk assessment (PRA) of a nuclear power plant for postulated hazard requires the development of fragility relationships for the plants' safety related equipment. The objective of this paper is to present some general results and conclusions concerning the development of these seismic fragility levels. Participation in fragility-related research and experience gained from the completion of several PRA studies of a variety of nuclear power plants have provided much insight as to the most vulnerable equipment and the most efficient use of resources for development of fragilities. Plants studied had seismic design bases ranging from very simple equivalent static analysis for some of the earlier plants to state-of-the-art complex multimode dyanamic analyses for plants currently under construction. Increased sophistication and rigor in seismic qualification of equipment has resulted for the most part in increased seismic resistance. The majority of equipment has been found, however, to possess more than adequate resistance to seismic loading regardless of the degree of sophistication utilized in design as long as seismic loading was included in the design process. This paper presents conclusions of the authors as to which items of equipment typically require an individual ''plant-specific'' fragility analysis and which can be treated in a generic fashion. In addition, general conclusions on the relative seismic capacity levels and most frequent failure modes are summarized for generic equipment groups

  20. Severe accident risks: An assessment for five US nuclear power plants: Appendices A, B, and C

    International Nuclear Information System (INIS)

    1990-12-01

    This report summarizes an assessment of the risks from severe accidents in five commercial nuclear power plants in the United States. These risks are measured in a number of ways, including: the estimated frequencies of core damage accidents from internally initiated accidents and externally initiated accidents for two or the plants; the performance of containment structures under severe accident loadings; the potential magnitude of radionuclide release and offsite consequences of such accidents; and the overall risk (the product of accident frequencies and consequences). Supporting this summary report are a large number of reports written under contract to NRC that provide the detailed discussion of the methods used and results obtained in these risk studies. Volume 2 of this report contains three appendices, providing greater detail on the methods used, an example risk calculation, and more detailed discussion of particular technical issues found important in the risk studies

  1. The risk of nuclear power plants for man. O risco das usinas nucleares para o homem

    Energy Technology Data Exchange (ETDEWEB)

    Freire-Maia, A [UNESP, Botucatu, SP (Brazil)

    1981-01-01

    The author analyzes the risk of nuclear power plants for man with respect to biological radiation effects, sources, level and radiation effects in man. He uses the three Mile Island accident as lesson in order to illustrate a situation potentially dangerous. (C.M.).

  2. Cancer rate in children in the vicinity of nuclear power plants

    International Nuclear Information System (INIS)

    Grosche, B.; Jung, T.; Weiss, W.

    2008-01-01

    The recent epidemiological study on childhood cancer in the vicinity of nuclear power plants (KiKK) shows that the cancer risk, especially the leukaemia risk, for children below the age of five in Germany increases with increasing proximity to the site of a nuclear power plant. Earlier ecological studies had found an increased leukaemia risk in children under five within a five-kilometre radius. However, the KiKK study used a case-control design and thus the results are more reliable. A clear trend could be ascertained indicating that the risk increases with increasing proximity of the place of residence to the site of a nuclear power plant. Further, the elevated risk was observed in the entire region under study, i.e. also outside the 5-km radius. As it was not possible to determine individual radiation exposures of the more than 6,000 children included in the study, the distance between the nearest site of a nuclear power plant and the place of residence was used as a substitute both for cases and for controls. The study also took into account other risk factors with known or assumed carcinogenic effect. However, no indication was found that the result could be explained by other risk factors than by vicinity of a nuclear power plant. This clear dependence of risk on the distance from the sites is indicative for a potential causal relationship, but it is no proof. (orig.)

  3. Proceeding of 35th domestic symposium on applications of structural reliability and risk assessment methods to nuclear power plants

    International Nuclear Information System (INIS)

    2005-06-01

    As the 35th domestic symposium of Atomic Energy Research Committee, the Japan Welding Engineering Society, the symposium was held titled as Applications of structural reliability/risk assessment methods to nuclear energy'. Six speakers gave lectures titled as 'Structural reliability and risk assessment methods', 'Risk-informed regulation of US nuclear energy and role of probabilistic risk assessment', 'Reliability and risk assessment methods in chemical plants', 'Practical structural design methods based on reliability in architectural and civil areas', 'Maintenance activities based on reliability in thermal power plants' and 'LWR maintenance strategies based on Probabilistic Fracture Mechanics'. (T. Tanaka)

  4. Collision risk in white-tailed eagles. Modelling kernel-based collision risk using satellite telemetry data in Smoela wind-power plant

    Energy Technology Data Exchange (ETDEWEB)

    May, Roel; Nygaard, Torgeir; Dahl, Espen Lie; Reitan, Ole; Bevanger, Kjetil

    2011-05-15

    Large soaring birds of prey, such as the white-tailed eagle, are recognized to be perhaps the most vulnerable bird group regarding risk of collisions with turbines in wind-power plants. Their mortalities have called for methods capable of modelling collision risks in connection with the planning of new wind-power developments. The so-called 'Band model' estimates collision risk based on the number of birds flying through the rotor swept zone and the probability of being hit by the passing rotor blades. In the calculations for the expected collision mortality a correction factor for avoidance behaviour is included. The overarching objective of this study was to use satellite telemetry data and recorded mortality to back-calculate the correction factor for white-tailed eagles. The Smoela wind-power plant consists of 68 turbines, over an area of approximately 18 km2. Since autumn 2006 the number of collisions has been recorded on a weekly basis. The analyses were based on satellite telemetry data from 28 white-tailed eagles equipped with backpack transmitters since 2005. The correction factor (i.e. 'avoidance rate') including uncertainty levels used within the Band collision risk model for white-tailed eagles was 99% (94-100%) for spring and 100% for the other seasons. The year-round estimate, irrespective of season, was 98% (95-99%). Although the year-round estimate was similar, the correction factor for spring was higher than the correction factor of 95% derived earlier from vantage point data. The satellite telemetry data may provide an alternative way to provide insight into relative risk among seasons, and help identify periods or areas with increased risk either in a pre- or post construction situation. (Author)

  5. Safety improvements made at the Loviisa nuclear power plant to reduce fire risks originating from the turbine generators

    International Nuclear Information System (INIS)

    Virolainen, T.; Marttila, J.; Aulamo, H.

    1998-01-01

    Comprehensive upgrading measures have been completed for the Loviisa Nuclear Power Plant (modified VVER440/V213). These were carried out from the start of the design phase and during operation to ensure safe plant shutdown in the event of a large turbine generator oil fire. These modifications were made mainly on a deterministic basis according to specific risk studies and fire analyses. As part of the probabilistic safety assessment, a fire risk analysis was made that confirmed the importance of these upgrading measures. In fact, they should be considered as design basis modifications for all VVER440 plants. (author)

  6. Sabotage at Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Purvis, James W.

    1999-07-21

    Recently there has been a noted worldwide increase in violent actions including attempted sabotage at nuclear power plants. Several organizations, such as the International Atomic Energy Agency and the US Nuclear Regulatory Commission, have guidelines, recommendations, and formal threat- and risk-assessment processes for the protection of nuclear assets. Other examples are the former Defense Special Weapons Agency, which used a risk-assessment model to evaluate force-protection security requirements for terrorist incidents at DOD military bases. The US DOE uses a graded approach to protect its assets based on risk and vulnerability assessments. The Federal Aviation Administration and Federal Bureau of Investigation conduct joint threat and vulnerability assessments on high-risk US airports. Several private companies under contract to government agencies use formal risk-assessment models and methods to identify security requirements. The purpose of this paper is to survey these methods and present an overview of all potential types of sabotage at nuclear power plants. The paper discusses emerging threats and current methods of choice for sabotage--especially vehicle bombs and chemical attacks. Potential consequences of sabotage acts, including economic and political; not just those that may result in unacceptable radiological exposure to the public, are also discussed. Applicability of risk-assessment methods and mitigation techniques are also presented.

  7. Sabotage at Nuclear Power Plants

    International Nuclear Information System (INIS)

    Purvis, James W.

    1999-01-01

    Recently there has been a noted worldwide increase in violent actions including attempted sabotage at nuclear power plants. Several organizations, such as the International Atomic Energy Agency and the US Nuclear Regulatory Commission, have guidelines, recommendations, and formal threat- and risk-assessment processes for the protection of nuclear assets. Other examples are the former Defense Special Weapons Agency, which used a risk-assessment model to evaluate force-protection security requirements for terrorist incidents at DOD military bases. The US DOE uses a graded approach to protect its assets based on risk and vulnerability assessments. The Federal Aviation Administration and Federal Bureau of Investigation conduct joint threat and vulnerability assessments on high-risk US airports. Several private companies under contract to government agencies use formal risk-assessment models and methods to identify security requirements. The purpose of this paper is to survey these methods and present an overview of all potential types of sabotage at nuclear power plants. The paper discusses emerging threats and current methods of choice for sabotage--especially vehicle bombs and chemical attacks. Potential consequences of sabotage acts, including economic and political; not just those that may result in unacceptable radiological exposure to the public, are also discussed. Applicability of risk-assessment methods and mitigation techniques are also presented

  8. Water regime of steam power plants

    International Nuclear Information System (INIS)

    Oesz, Janos

    2011-01-01

    The water regime of water-steam thermal power plants (secondary side of pressurized water reactors (PWR); fossil-fired thermal power plants - referred to as steam power plants) has changed in the past 30 years, due to a shift from water chemistry to water regime approach. The article summarizes measures (that have been realised by chemists of NPP Paks) on which the secondary side of NPP Paks has become a high purity water-steam power plant and by which the water chemistry stress corrosion risk of heat transfer tubes in the VVER-440 steam generators was minimized. The measures can also be applied to the water regime of fossil-fired thermal power plants with super- and subcritical steam pressure. Based on the reliability analogue of PWR steam generators, water regime can be defined as the harmony of construction, material(s) and water chemistry, which needs to be provided in not only the steam generators (boiler) but in each heat exchanger of steam power plant: - Construction determines the processes of flow, heat and mass transfer and their local inequalities; - Material(s) determines the minimal rate of general corrosion and the sensitivity for local corrosion damage; - Water chemistry influences the general corrosion of material(s) and the corrosion products transport, as well as the formation of local corrosion environment. (orig.)

  9. Are atomic power plants saver than nuclear power plants

    International Nuclear Information System (INIS)

    Roeglin, H.C.

    1977-01-01

    It is rather impossible to establish nuclear power plants against the resistance of the population. To prevail over this resistance, a clarification of the citizens-initiatives motives which led to it will be necessary. This is to say: It is quite impossible for our population to understand what really heappens in nuclear power plants. They cannot identify themselves with nuclear power plants and thus feel very uncomfortable. As the total population feels the same way it is prepared for solidarity with the citizens-initiatives even if they believe in the necessity of nuclear power plants. Only an information-policy making transparent the social-psychological reasons of the population for being against nuclear power plants could be able to prevail over the resistance. More information about the technical procedures is not sufficient at all. (orig.) [de

  10. Issues related to structural aging in probabilistic risk assessment of nuclear power plants

    International Nuclear Information System (INIS)

    Ellingwood, Bruce R.

    1998-01-01

    Structural components and systems have an important safety function in nuclear power plants. Although they are essentially passive under normal operating conditions, they play a key role in mitigating the impact of extreme environmental events such as earthquakes, winds, fire and floods on plant safety. Moreover, the importance of structural components and systems in accident mitigation is amplified by common-cause effects. Reinforced concrete structural components and systems in NPPs are subject to a phenomenon known as aging, leading to time-dependent changes in strength and stiffness that may impact their ability to withstand various challenges during their service lives from operation, the environment and accidents. Time-dependent changes in structural properties as well as challenges to the system are random in nature. Accordingly, condition assessment of existing structures should be performed within a probabilistic framework. The mathematical formalism of a probabilistic risk assessment (PRA) provides a means for identifying aging structural components that may play a significant role in mitigating plant risk. Structural condition assessments supporting a decision regarding continued service can be rendered more efficient if guided by the logic of a PRA

  11. Benefits and risks of nuclear power

    International Nuclear Information System (INIS)

    Barnert, H.; Borsch, P.; Feldmann, A.; Merz, E.; Muench, E.; Oesterwind, D.; Voss, A.

    1977-03-01

    Discussion, in a popular form, of issues of interest for an unemotional information of the public on problems of nuclear power: 1) Energy consumption, its assumed growth, and possible ways of supply; 2) the physical fundamental and technical realisation of power generation by nuclear fission; 3) problems of the fuel cycle and possible solutions; 4) the effects of radioactive radiation; 5) the safety of nuclear power plants and the risks of nuclear power as compared to other technical and natural risks. (orig./HP) [de

  12. In-plant reliability data base for nuclear power plant components: data collection and methodology report

    International Nuclear Information System (INIS)

    Drago, J.P.; Borkowski, R.J.; Pike, D.H.; Goldberg, F.F.

    1982-07-01

    The development of a component reliability data for use in nuclear power plant probabilistic risk assessments and reliabiilty studies is presented in this report. The sources of the data are the in-plant maintenance work request records from a sample of nuclear power plants. This data base is called the In-Plant Reliability Data (IPRD) system. Features of the IPRD system are compared with other data sources such as the Licensee Event Report system, the Nuclear Plant Reliability Data system, and IEEE Standard 500. Generic descriptions of nuclear power plant systems formulated for IPRD are given

  13. Application of risk-informed methods to in-service piping inspection in Framatome type nuclear power plants

    International Nuclear Information System (INIS)

    Kim, Jin Hoi; Lee, Jeong Seok; Yun, Eun Sub

    2014-01-01

    The Pressurized water reactor owners group (PWROG) developed and applied a risk-informed in-service inspection (RI-ISI) program, as an alternative to the existing ASME Section XI sampling inspection method. The RI-ISI programs enhance overall safety by focusing inspections of piping at high safety significance (HSS) locations where failure mechanisms are likely to be present. Additionally, the RI-ISI program can reduce nondestructive evaluation (NDE) exams, man-rem exposure for inspectors, and inspection time, among other benefits. The RI-ISI method of in-service piping inspection was applied to 3 units (KSNPs: Korea standard nuclear power plants) and is being deployed to the other units. In this paper, the results of RI-ISI for a Framatome type (France CPI) nuclear power plant are presented. It was concluded that application of RI-ISI to the plant could enhance and maintain plant safety, as well as provide the benefits of greater reliability.

  14. Employing modern power plant simulators in nuclear power plants

    International Nuclear Information System (INIS)

    Niedorf, V.; Storm, J.

    2005-01-01

    At the present state of the art, modern power plant simulators are characterized by new qualitative features, thus enabling operators to use them far beyond the traditional field of training. In its first part, this contribution presents an overview of the requirements to be met by simulators for multivalent uses. In part two, a survey of the uses and perspectives of simulation technology in power plants is presented on the basis of experience accumulated by Rheinmetall Defence Electronics (RDE).Modern simulators are shown to have applications by far exceeding traditional training areas. Modular client - sever systems on standard computers allow inexpensive uses to be designed at several levels, thus minimizing maintenance cost. Complex development and running time environments, like the SEMS developed by RDE, have made power plant simulators the workhorses of power plant engineers in all power plant areas. (orig.)

  15. Deterministic and probabilistic approach to determine seismic risk of nuclear power plants; a practical example

    International Nuclear Information System (INIS)

    Soriano Pena, A.; Lopez Arroyo, A.; Roesset, J.M.

    1976-01-01

    The probabilistic and deterministic approaches for calculating the seismic risk of nuclear power plants are both applied to a particular case in Southern Spain. The results obtained by both methods, when varying the input data, are presented and some conclusions drawn in relation to the applicability of the methods, their reliability and their sensitivity to change

  16. Reactor safety study. An assessment of accident risks in U. S. commercial nuclear power plants. Executive summary: main report. [PWR and BWR

    Energy Technology Data Exchange (ETDEWEB)

    1975-10-01

    Information is presented concerning the objectives and organization of the reactor safety study; the basic concepts of risk; the nature of nuclear power plant accidents; risk assessment methodology; reactor accident risk; and comparison of nuclear risks to other societal risks.

  17. Analysis of risk-dominant sequences by MAAP3.0 for Kuosheng Nuclear Power Plant

    International Nuclear Information System (INIS)

    Lin, J.D.; Chieng, C.C.; Wang, T.K.; Hsiue, R.K.

    1987-01-01

    Kuosheng Nuclear Power Plant is the first operating model-6/Mark III boiling water reactor (BWR6/Mark III) in the world, and a probabilistic risk assessment (PRA) has been performed to determine the likely frequencies of core melt accidents and the magnitude, composition, and fraction of fission products released in these accidents. The final report of this PRA indicates that categories 8 and 15 are ranked No. 1 by risk index (the product of release frequency and release fraction) and release frequency, respectively. The dominant contributors of these two categories are frequent earthquakes and typhoons

  18. Seismic PSA method for multiple nuclear power plants in a site

    Energy Technology Data Exchange (ETDEWEB)

    Hakata, Tadakuni [Nuclear Safety Commission, Tokyo (Japan)

    2007-07-15

    The maximum number of nuclear power plants in a site is eight and about 50% of power plants are built in sites with three or more plants in the world. Such nuclear sites have potential risks of simultaneous multiple plant damages especially at external events. Seismic probabilistic safety assessment method (Level-1 PSA) for multi-unit sites with up to 9 units has been developed. The models include Fault-tree linked Monte Carlo computation, taking into consideration multivariate correlations of components and systems from partial to complete, inside and across units. The models were programmed as a computer program CORAL reef. Sample analysis and sensitivity studies were performed to verify the models and algorithms and to understand some of risk insights and risk metrics, such as site core damage frequency (CDF per site-year) for multiple reactor plants. This study will contribute to realistic state of art seismic PSA, taking consideration of multiple reactor power plants, and to enhancement of seismic safety. (author)

  19. Kansas Power Plants

    Data.gov (United States)

    Kansas Data Access and Support Center — The Kansas Power Plants database depicts, as point features, the locations of the various types of power plant locations in Kansas. The locations of the power plants...

  20. Global risk from the atmospheric dispersion of radionuclides by nuclear power plant accidents in the coming decades

    Energy Technology Data Exchange (ETDEWEB)

    Christoudias, T.; Proestos, Y. [The Cyprus Institute, Nicosia (Cyprus); Lelieveld, J. [The Cyprus Institute, Nicosia (Cyprus); Max Planck Institute for Chemistry, Mainz (Germany)

    2014-07-01

    We estimate the global risk from the release and atmospheric dispersion of radionuclides from nuclear power plant accidents using the EMAC atmospheric chemistry-general circulation model. We included all nuclear reactors that are currently operational, under construction and planned or proposed. We implemented constant continuous emissions from each location in the model and simulated atmospheric transport and removal via dry and wet deposition processes over 20 years (2010-2030), driven by boundary conditions based on the IPCC A2 future emissions scenario. We present global overall and seasonal risk maps for potential surface layer concentrations and ground deposition of radionuclides, and estimate potential doses to humans from inhalation and ground-deposition exposures to radionuclides. We find that the risk of harmful doses due to inhalation is typically highest in the Northern Hemisphere during boreal winter, due to relatively shallow boundary layer development and limited mixing. Based on the continued operation of the current nuclear power plants, we calculate that the risk of radioactive contamination to the citizens of the USA will remain to be highest worldwide, followed by India and France. By including stations under construction and those that are planned and proposed, our results suggest that the risk will become highest in China, followed by India and the USA.

  1. Environmental impact assessment of coal power plants in operation

    OpenAIRE

    Bartan Ayfer; Kucukali Serhat; Ar Irfan

    2017-01-01

    Coal power plants constitute an important component of the energy mix in many countries. However, coal power plants can cause several environmental risks such as: climate change and biodiversity loss. In this study, a tool has been proposed to calculate the environmental impact of a coal-fired thermal power plant in operation by using multi-criteria scoring and fuzzy logic method. We take into account the following environmental parameters in our tool: CO, SO2, NOx, particulate matter, fly as...

  2. Assessment of environmental impacts of nuclear power plants

    International Nuclear Information System (INIS)

    Horacek, P.

    1990-01-01

    The effects of normal operation and of accidents are analyzed. It is pointed out that the public is insufficiently informed, which bears anxiety and prejudice. The effective dose equivalents for the population and for the individual, measured during operation of the Bohunice nuclear power plants are listed and compared with those from natural background and from medical applications. The possible radioactive contamination of a large area of agricultural soil is the highest specific risk of nuclear power plant operation. Problems are growing related to spent fuel disposal and eventually to the decommissioning of the power plant itself. (M.D.). 1 tab., 8 refs

  3. Risk management for independent power projects

    International Nuclear Information System (INIS)

    Owen, J.L.

    1993-01-01

    Independent Power, where electric utilities or other bulk electric power users contract with individual electric power generation facilities to meet their projected long term power needs, has grown dramatically over the past ten years or more. This concept, to contract with Independent Power Producers (IPP), is not a new concept and in fact goes back to the early formation of the electric power industry in this country and worldwide. Successful Risk Management is the foundation for ultimate project completion and operation in fulfilling the expectations of all parties. The primary risks associated with the development of Independent Power projects include: predicting long term fuel availability and cost; predicting long term price for the deliverable of electricity; site selection, site characteristics and permitting; innovative or evolving technology; project execution (design and construction), and; lifetime O ampersand M costs and plant reliability. This paper focuses on the risks inherent in the development of IPPs and addresses the management of these risks

  4. Risk assessment and nuclear power

    International Nuclear Information System (INIS)

    Bodansky, D.

    1982-01-01

    The range of risk perceptions involving nuclear power is so great that there is little hope of bridging extreme positions, but a consensus based upon reasoned discussion among uncommitted people could determine a sensible path. Our concerns over the uncertainties of risk assessment have made it increasingly difficult to make responsible decisions fast enough to deal with modern needs. The result is an immobility in energy matters that can point to a 2% reduction in oil use as its only triumph. The risk of nuclear war as a result of military action over energy issues suggests to some that the solution is to abolish nuclear power (however impractical) and to others that a rapid spread of nuclear power will eliminate energy as an incentive for war. If nuclear war is the major risk to consider, risk assessments need to include the risks of war, as well as those of carbon dioxide buildup and socio-economic disruptions, all of which loom larger than the risks of nuclear-plant accidents. Energy choices should be aimed at diminishing these major risks, even if they include the use of nuclear power. 26 references

  5. Predicting the environmental risks of radioactive discharges from Belgian nuclear power plants.

    Science.gov (United States)

    Vandenhove, H; Sweeck, L; Vives I Batlle, J; Wannijn, J; Van Hees, M; Camps, J; Olyslaegers, G; Miliche, C; Lance, B

    2013-12-01

    An environmental risk assessment (ERA) was performed to evaluate the impact on non-human biota from liquid and atmospheric radioactive discharges by the Belgian Nuclear Power Plants (NPP) of Doel and Tihange. For both sites, characterisation of the source term and wildlife population around the NPPs was provided, whereupon the selection of reference organisms and the general approach taken for the environmental risk assessment was established. A deterministic risk assessment for aquatic and terrestrial ecosystems was performed using the ERICA assessment tool and applying the ERICA screening value of 10 μGy h(-1). The study was performed for the radioactive discharge limits and for the actual releases (maxima and averages over the period 1999-2008 or 2000-2009). It is concluded that the current discharge limits for the Belgian NPPs considered do not result in significant risks to the aquatic and terrestrial environment and that the actual discharges, which are a fraction of the release limits, are unlikely to harm the environment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Cooling water in the study of nuclear power plants sites

    International Nuclear Information System (INIS)

    Martinez, J.J.C.

    1990-01-01

    The location of an electric power plant has its limitations as regards the availability of apt sites. The radiosanitary risk, seismic risk and the overload capacity of the ground can be generically enumerated, being the cooling water availability for an electric power plant a basic requirement. Diverse cooling systems may be employed but the aim must always be that thermal contamination in the immediate environment be the least possible. (Author) [es

  7. Hydroelectric Power Plants Dobsina

    International Nuclear Information System (INIS)

    Majercak, V.; Srenkelova, Z.; Kristak, J.G.

    1997-01-01

    In this brochure the Hydroelectric Power Plants Dobsina, (VED), subsidiary of the utility Slovenske Elektrarne, a.s. (Slovak Electric, plc. Bratislava) are presented. VED is mainly aimed at generating peak-load electrical energy and maintenance of operational equipment. Reaching its goals, company is first of all focused on reliability of production, economy and effectiveness, keeping principles of work safety and industry safety standards and also ecology. VED operates eight hydroelectric power plants, from which PVE Ruzin I and PVE Dobsina I are pump storage ones and they are controlled directly by the Slovak Energy Dispatch Centre located in Zilina thought the system LS 3200. Those power plants participate in secondary regulation of electrical network of Slovakia. They are used to compensate balance in reference to foreign electrical networks and they are put into operation independently from VED. Activity of the branch is focused mainly on support of fulfilment of such an important aim as electric network regulation. Beginnings of the subsidiary Hydroelectric Power Plants Dobsina are related to the year of 1948. After commissioning of the pump storage Hydroelectric Power Plants Dobsina in 1953, the plant started to carry out its mission. Since that time the subsidiary has been enlarged by other seven power plants, through which it is fulfilling its missions nowadays. The characteristics of these hydroelectric power plants (The pump-storage power plant Dobsina, Small hydroelectric power plant Dobsina II, Small hydroelectric power plant Rakovec, Small hydroelectric power plant Svedlar, Hydroelectric power plant Domasa, The pump-storage power plant Ruzin, and Small hydroelectric power plant Krompachy) are described in detail. Employees welfare and public relations are presented

  8. Radiological protection and nuclear power plants

    International Nuclear Information System (INIS)

    Delpla, M.

    Dosimetric results obtained inside and outside nuclear power plants are examined with a review to proposing revision of the radiological protection standards. Dose limits are considered with regard to leukemia and genetic effects. Other topics discussed are: observed collective damage and mean risk; lethal exposure; healing and sign change of additional risk; and genetic effects of radiation on mice

  9. Comparative studies between nuclear power plants and hydroelectric power plants

    International Nuclear Information System (INIS)

    Menegassi, J.

    1984-01-01

    This paper shows the quantitative evolution of the power plants in the main countries of the world. The Brazilian situation is analysed, with emphasys in the technical and economical aspects related to power production by hidroelectric or nuclear power plants. The conclusion is that the electricity produced by hidro power plants becomes not economics when is intended to be produced at large distances from the demand centers. (Author) [pt

  10. Validation of seismic probabilistic risk assessments of nuclear power plants

    International Nuclear Information System (INIS)

    Ellingwood, B.

    1994-01-01

    A seismic probabilistic risk assessment (PRA) of a nuclear plant requires identification and information regarding the seismic hazard at the plant site, dominant accident sequences leading to core damage, and structure and equipment fragilities. Uncertainties are associated with each of these ingredients of a PRA. Sources of uncertainty due to seismic hazard and assumptions underlying the component fragility modeling may be significant contributors to uncertainty in estimates of core damage probability. Design and construction errors also may be important in some instances. When these uncertainties are propagated through the PRA, the frequency distribution of core damage probability may span three orders of magnitude or more. This large variability brings into question the credibility of PRA methods and the usefulness of insights to be gained from a PRA. The sensitivity of accident sequence probabilities and high-confidence, low probability of failure (HCLPF) plant fragilities to seismic hazard and fragility modeling assumptions was examined for three nuclear power plants. Mean accident sequence probabilities were found to be relatively insensitive (by a factor of two or less) to: uncertainty in the coefficient of variation (logarithmic standard deviation) describing inherent randomness in component fragility; truncation of lower tail of fragility; uncertainty in random (non-seismic) equipment failures (e.g., diesel generators); correlation between component capacities; and functional form of fragility family. On the other hand, the accident sequence probabilities, expressed in the form of a frequency distribution, are affected significantly by the seismic hazard modeling, including slopes of seismic hazard curves and likelihoods assigned to those curves

  11. Circumstances in a nuclear power plant. Organization of risk and institutionalization of safety; Omstaendigheter paa ett kaernkraftverk. Organisering av risk och institutionalisering av saekerhet

    Energy Technology Data Exchange (ETDEWEB)

    Wessblad, H

    1999-01-01

    Risk societies are made of risk organisations. This dissertation is an ethnographic study of a risk organisation, of a nuclear power plant. Risk organizations have larger demands on their organization than traditional companies have. Risk societies, to come or already present, have new political agendas. Within a risk society the major task is to reduce and distribute the negative side effects of industrial production, not to increase and distribute well-fare in society, as it has been in an industrial society. This is a study of a risk organisation claimed to produce these negative side effects. The title of this thesis relates to specific occasions in the organisation. The branch concept, circumstances, defines `situations beyond normal performance`, which are to be reported to the nuclear authorities. These circumstances are rarely endangering man or material, but given the nature of nuclear power production, they have a potential to escalate to something larger. This dissertation focuses on how the organisation deals with these issues and reproduces safety as something taken-for-granted. The material is gathered using participant observation of different functions in the plant. The work is based on narration of situations, meetings, interviews, and small talk etc, in every-day-interaction. The dissertation describes how business-as-usual produce safety. It is a description of how values, norms, attitudes, ideas, knowledge are produced and reproduced. These issues are discussed mainly in an institutional theory perspective. What has become apparent is that functions governed by routines and instructions tend to be more flexible and reflecting than those dealing with new tasks, such as problem solving projects. Thus, these new projects tend to reproduce earlier established procedures. Through the narration of the various functions of the plant joined with theoretical discussions, different themes have been found describing how the organisation deals with

  12. FIRE SAFETY IN NUCLEAR POWER PLANTS: A RISK-INFORMED AND PERFORMANCE-BASED APPROACH

    International Nuclear Information System (INIS)

    AZARM, M.A.; TRAVIS, R.J.

    1999-01-01

    The consideration of risk in regulatory decision-making has long been a part of NRC's policy and practice. Initially, these considerations were qualitative and were based on risk insights. The early regulations relied on good practices, past insights, and accepted standards. As a result, most NRC regulations were prescriptive and were applied uniformly to all areas within the regulatory scope. Risk technology is changing regulations by prioritizing the areas within regulatory scope based on risk, thereby focusing on the risk-important areas. Performance technology, on the other hand, is changing the regulations by allowing requirements to be adjusted based on the specific performance expected and manifested, rather than a prior prescriptive requirement. Consistent with the objectives of risk-informed and performance-based regulatory requirements, BNL evaluated the feasibility of applying risk- and performance-technologies to modifying NRC's current regulations on fire protection for nuclear power plants. This feasibility study entailed several case studies (trial applications). This paper describes the results of two of them. Besides the case studies, the paper discusses an overall evaluation of methodologies for fire-risk analysis to support the risk-informed regulation. It identifies some current shortcomings and proposes some near-term solutions

  13. Reanalysis of Epidemiological Investigation of Cancer Risk among People Residing near Nuclear Power Plants in South Korea.

    Science.gov (United States)

    Kim, Jeong-Min; Kim, Myoung-Hee; Ju, Young-Su; Hwang, Seung-Sik; Ha, Mina; Kim, Bong-Kyu; Zoh, Kyung Ehi; Paek, Domyung

    2018-03-09

    Background : A 20-year follow-up study on cancer incidence among people living near nuclear power plants in South Korea ended in 2011 with a finding of significantly, but inconsistently, elevated thyroid cancer risk for females. Reanalysis of the original study was carried out to examine the dose-response relationship further, and to investigate any evidence of detection bias. Methods : In addition to replicating the original Cox proportional hazards models, nested case-control analysis was carried out for all subjects and for four different birth cohorts to examine the effects of excluding participants with pre-existing cancer history at enrollment. The potential for detection bias was investigated using the records of medical utilization and voluntary health checks of comparison groups. Results : The overall risk profile of the total sample was similar to that of the original study. However, in the stratified analysis of four birth cohorts, the cancer risk among people living near nuclear power plants became higher in younger birth cohorts. This was especially true for thyroid cancers of females (hazard ratio (HR) 3.38) and males (HR 1.74), female breast cancers (HR 2.24), and radiation-related cancers (HR 1.59 for males, HR 1.77 for females), but not for radiation-insensitive cancers (HR 0.59 for males, HR 0.98 for females). Based on medical records and health check reports, we found no differences between comparison groups that could have led to detection bias. Conclusions : The overall results suggest elevated risk of radiation-related cancers among residents living near nuclear power plants, controlling for the selective survival effect. This is further supported by the lack of evidence of detection bias and by records of environmental exposure from radiation waste discharge.

  14. Reanalysis of Epidemiological Investigation of Cancer Risk among People Residing near Nuclear Power Plants in South Korea

    Directory of Open Access Journals (Sweden)

    Jeong-Min Kim

    2018-03-01

    Full Text Available Background: A 20-year follow-up study on cancer incidence among people living near nuclear power plants in South Korea ended in 2011 with a finding of significantly, but inconsistently, elevated thyroid cancer risk for females. Reanalysis of the original study was carried out to examine the dose–response relationship further, and to investigate any evidence of detection bias. Methods: In addition to replicating the original Cox proportional hazards models, nested case-control analysis was carried out for all subjects and for four different birth cohorts to examine the effects of excluding participants with pre-existing cancer history at enrollment. The potential for detection bias was investigated using the records of medical utilization and voluntary health checks of comparison groups. Results: The overall risk profile of the total sample was similar to that of the original study. However, in the stratified analysis of four birth cohorts, the cancer risk among people living near nuclear power plants became higher in younger birth cohorts. This was especially true for thyroid cancers of females (hazard ratio (HR 3.38 and males (HR 1.74, female breast cancers (HR 2.24, and radiation-related cancers (HR 1.59 for males, HR 1.77 for females, but not for radiation-insensitive cancers (HR 0.59 for males, HR 0.98 for females. Based on medical records and health check reports, we found no differences between comparison groups that could have led to detection bias. Conclusions: The overall results suggest elevated risk of radiation-related cancers among residents living near nuclear power plants, controlling for the selective survival effect. This is further supported by the lack of evidence of detection bias and by records of environmental exposure from radiation waste discharge.

  15. Sea water pumping-up power plant system combined with nuclear power plant

    International Nuclear Information System (INIS)

    Ichiki, Tadaharu; Tanaka, Masayuki.

    1991-01-01

    It is difficult to find a site suitable to construction for a sea water pumping-up power plant at a place relatively near the electric power consumption area. Then, a nuclear power plant is set at the sea bottom or the land portion of a sea shore near the power consumption area. A cavity is excavated underground or at the bottom of the sea in the vicinity of the power plant to form a lower pond, and the bottom of the sea, as an upper pond and the lower pond are connected by a water pressure pipe and a water discharge pipe. A pump water turbine is disposed therebetween, to which electric power generator is connected. In addition, an ordinary or emergency cooling facility in the nuclear power plant is constituted such that sea water in the cavity is supplied by a sea water pump. Accordingly, the sea water pumping-up plant system in combination with the nuclear power plant is constituted with no injuring from salts to animals and plants on land in the suburbs of a large city. The cost for facilities for supplying power from a remote power plant to large city areas and power loss are decreased and stable electric power can be supplied. (N.H.)

  16. Risk zoning around nuclear power plants in comparison to other major hazardous industrial installations

    International Nuclear Information System (INIS)

    Kirchsteiger, Christian

    2006-01-01

    The background and current status of the information basis leading to the definition of risk and emergency zones around Nuclear Power Plants (NPPs) in different countries in Europe and beyond are analysed. Although dependable plant-specific Probabilistic Safety Assessment (PSA) of Level 2 and/or Level 3 could in principle provide sufficiently detailed input to define the geographical dimension of a NPP's risk and emergency zones, the analysis of the status in some European and other countries shows that other, 'deterministic' approaches using a Reference Accident are actually used in practice. Regarding use of Level 2 PSA for emergency planning, the approach so far has been to use the Level 2 PSA information retrospectively to provide the justification for the choice of Reference Accident(s) used to define the emergency plans and Emergency Planning Zones (EPZs). There are significant differences in the EPZs that are defined in different countries, ranging from about 1 km to 30 km. Further, there is a striking contrast in the extent of using probabilistic information to define emergency zones between the nuclear and other high risk industry sectors, such as the chemical process industry, and the reasons for these differences are not entirely clear, but seem to be more related to risk perception than actual risk potential. Finally, based on consensus discussions at a recent JRC/OECD International Seminar on Risk and Emergency Zoning around NPPs, recommendations are given in the areas of more comprehensive use of available risk information for risk zoning purposes, risk communication and comparative risk assessment. (author)

  17. Evaluation of piping reliability and failure data for use in risk-based inspections of nuclear power plants

    International Nuclear Information System (INIS)

    Vasconcelos, V. de; Soares, W.A.; Costa, A.C.L. da; Rabello, E.G.; Marques, R.O.

    2016-01-01

    During operation of industrial facilities, components and systems can deteriorate over time, thus increasing the possibility of accidents. Risk-Based Inspection (RBI) involves inspection planning based on information about risks, through assessing of probability and consequence of failures. In-service inspections are used in nuclear power plants, in order to ensure reliable and safe operation. Traditional deterministic inspection approaches investigate generic degradation mechanisms on all systems. However, operating experience indicates that degradation occurs where there are favorable conditions for developing a specific mechanism. Inspections should be prioritized at these places. Risk-Informed In-service Inspections (RI-ISI) are types of RBI that use Probabilistic Safety Assessment results, increasing reliability and plant safety, and reducing radiation exposure. These assessments use both available generic reliability and failure data, as well as plant specific information. This paper proposes a method for evaluating piping reliability and failure data important for RI-ISI programs, as well as the techniques involved. (author)

  18. Evaluation of piping reliability and failure data for use in risk-based inspections of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Vasconcelos, V. de; Soares, W.A.; Costa, A.C.L. da; Rabello, E.G.; Marques, R.O., E-mail: vasconv@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2016-07-01

    During operation of industrial facilities, components and systems can deteriorate over time, thus increasing the possibility of accidents. Risk-Based Inspection (RBI) involves inspection planning based on information about risks, through assessing of probability and consequence of failures. In-service inspections are used in nuclear power plants, in order to ensure reliable and safe operation. Traditional deterministic inspection approaches investigate generic degradation mechanisms on all systems. However, operating experience indicates that degradation occurs where there are favorable conditions for developing a specific mechanism. Inspections should be prioritized at these places. Risk-Informed In-service Inspections (RI-ISI) are types of RBI that use Probabilistic Safety Assessment results, increasing reliability and plant safety, and reducing radiation exposure. These assessments use both available generic reliability and failure data, as well as plant specific information. This paper proposes a method for evaluating piping reliability and failure data important for RI-ISI programs, as well as the techniques involved. (author)

  19. Guidance for emergency planning in nuclear power plants

    International Nuclear Information System (INIS)

    Magnusson, Tommy; Ekdahl, Maria

    2008-06-01

    Ringhals has been a model for this study, but the purpose has been to make the report applicable at all nuclear power plants in Sweden. The work has been done in close co-operation with the Swedish nuclear power plants and Rescue Services in the nuclear power municipalities Oesthammar, Oskarshamn, and Varberg. The internal fire brigade at the nuclear power plants has also been involved. A document will also be published as a further guidance at efforts of the type fires, which are mentioned in the enclosed document. After a fire in a switchgear room in 2005 the need of making the existing effort planning more effective at nuclear power plants was observed. The idea with the planning is to plan the effort in order to give the operational and emergency staff a good and actual support to come to a decision and to start the mission without delay. The risk information is showed by planning layouts, symbols and drawings as basis, give risk information and effort information. The effort information shows outer arrangements, manual action points, fire installations, passive fire safety etc. The risk information is shown by risk symbols. Their purpose is to give a fast overview of the existing risks. Reactor safety effects is the ruling influence if an effort has to be done in order to secure safety for a third person. In order to make an effort in an area personal risks for rescue staff, such as electricity risks, radiological risks, chemicals and gas bottles with compressed gases, has to be eliminated. For complicated missions detailed instructions are needed in order to handle specific risks. In a group discussion different people with pertinent knowledge has to value which problematic efforts need detailed instruction. Missions that have to be analyzed in a work group as above are: fire may affect the reactor safety, fire that may threaten the structural integrity, chemical discharge with big consequence on environment/third person and handling of gas system (compressed

  20. Common Risk Target for severe accidents of nuclear power plants based on IAEA INES scale

    International Nuclear Information System (INIS)

    Vitázková, Jiřina; Cazzoli, Errico

    2013-01-01

    The IAEA has repeatedly recommended that the nuclear community should arrive at a common understanding and definition of safety goals for severe accidents in nuclear power plants. The recommendation has only found partial answers, despite the numerous working groups and forums devoted to this effort. The most widely accepted definition of goals is based on the concept of Large (Early) Release Frequencies (L(E)RF) and its derivatives, a surrogate concept derived from results of Probabilistic Safety Assessments (PSAs) which was first introduced in the USA almost twenty years ago and much later accepted by the USNRC for risk informed decision making, but not for safety demonstrations. Other types of Safety Goals have been adopted by some nuclear authorities, but the main drawback of all current definitions is that they may apply only to LWRs. The lack of unifying safety/risk parameter throughout of PSAs worldwide is the basis of the present work, and an attempt is made to arrive at the definition of a Risk Target for severe accidents in NPPs, consistent with the IAEA definitions having a technical basis, which can be adopted without modifications for Generation IV power plants. The proposal of Common Risk Target in this work represents an attempt to define a Common Risk Target based on technical reasoning, reflecting IAEA definitions as well as harmonization requirements raised by the whole European Community in various OECD, ASAMPSA2 and SARNET (Guentay et al., 2006) conclusions and Council Directive of The European Union (Community Framework, 2009) as well as lastly performed stress tests of nuclear power plants throughout the Europe (Peer Review Report, 2012). The basic concept of CRT was first introduced and developed within the European project ASAMPSA2 by the authors of this article and was accepted by majority of world PSA experts participating in final evaluation and survey of the project (Guentay, 2011). In the proposed Risk Target concept an innovative

  1. Common Risk Target for severe accidents of nuclear power plants based on IAEA INES scale

    Energy Technology Data Exchange (ETDEWEB)

    Vitázková, Jiřina, E-mail: jirina@snus.sk [Vitázková-Vitty, Sládkovičova 24, 900 28 Ivanka pri Dunaji (Slovakia); Cazzoli, Errico, E-mail: erik.cazzoli@gmx.net [Cazzoli Consulting, Wiesenweg 14, CH-5415 Nussbaumen (Switzerland)

    2013-09-15

    The IAEA has repeatedly recommended that the nuclear community should arrive at a common understanding and definition of safety goals for severe accidents in nuclear power plants. The recommendation has only found partial answers, despite the numerous working groups and forums devoted to this effort. The most widely accepted definition of goals is based on the concept of Large (Early) Release Frequencies (L(E)RF) and its derivatives, a surrogate concept derived from results of Probabilistic Safety Assessments (PSAs) which was first introduced in the USA almost twenty years ago and much later accepted by the USNRC for risk informed decision making, but not for safety demonstrations. Other types of Safety Goals have been adopted by some nuclear authorities, but the main drawback of all current definitions is that they may apply only to LWRs. The lack of unifying safety/risk parameter throughout of PSAs worldwide is the basis of the present work, and an attempt is made to arrive at the definition of a Risk Target for severe accidents in NPPs, consistent with the IAEA definitions having a technical basis, which can be adopted without modifications for Generation IV power plants. The proposal of Common Risk Target in this work represents an attempt to define a Common Risk Target based on technical reasoning, reflecting IAEA definitions as well as harmonization requirements raised by the whole European Community in various OECD, ASAMPSA2 and SARNET (Guentay et al., 2006) conclusions and Council Directive of The European Union (Community Framework, 2009) as well as lastly performed stress tests of nuclear power plants throughout the Europe (Peer Review Report, 2012). The basic concept of CRT was first introduced and developed within the European project ASAMPSA2 by the authors of this article and was accepted by majority of world PSA experts participating in final evaluation and survey of the project (Guentay, 2011). In the proposed Risk Target concept an innovative

  2. Licensing issues in the context of terrorist attacks on nuclear power plants

    International Nuclear Information System (INIS)

    Danwitz, T. von

    2002-01-01

    The terrorist attack on the World Trade Center in September 2001 has prompted enhanced nuclear risk awareness among the German population. But in the current public debate about the safety of nuclear power plants in Germany in times of new dimensions of danger, aspects such as the role of the constitutional law, the German Atomic Energy Act, and the regulatory system governing nuclear power plant licensing in the context of protection and safety have not been addressed. The author therefore discusses the German nuclear power plant licensing law and administrative regime, elaborating on the significance attributed in those bodies of law to risks like terrorist attacks on nuclear power plants. (orig./CB) [de

  3. Nuclear power investment risk economic model

    International Nuclear Information System (INIS)

    Houghton, W.J.; Postula, F.D.

    1985-12-01

    This paper describes an economic model which was developed to evaluate the net costs incurred by a utility due to an accident induced outage at a nuclear power plant. During such an outage the portion of the plant operating costs associated with power production are saved; however, the owning utility faces a sizable expense as fossil fuels are burned as a substitute for the incapacitated nuclear power. Additional expenses are incurred by the utility for plant repair and if necessary, decontamination costs. The model makes provision for mitigating these costs by sales of power, property damage insurance payments, tax write-offs and increased rates. Over 60 economic variables contribute to the net cost uncertainty. The values of these variables are treated as uncertainty distributions and are used in a Monte carlo computer program to evaluate the cost uncertainty (investment risk) associated with damage which could occur from various categories of initiating accidents. As an example, results of computations for various levels of damage associated with a loss of coolant accident are shown as a range of consequential plant downtime and unrecovered cost. A typical investment risk profile is shown for these types of accidents. Cost/revenue values for each economic factor are presented for a Three Mile Island - II type accident, e.g., uncontrolled core heatup. 4 refs., 6 figs., 3 tabs

  4. Coping with nuclear power risks: the electric utility incentives

    International Nuclear Information System (INIS)

    Starr, C.; Whipple, C.

    1982-01-01

    The financial risks associated with nuclear power accidents are estimated by interpolating between frequency-vs.-severity data from routine outages and the frequency-vs.-severity estimates from the Nuclear Regulatory Commission's (NRC's) Reactor Safety Study (WASH-1400). This analysis indicates that the expected costs of plant damage and lost power production are large compared to the public risks estimated in WASH-1400, using values from An Approach to Quantitative Safety Goals for Nuclear Power Plants (NUREG-0739), prepared by the NRC Advisory Committee on Reactor Safeguards. Analyses of the cost-effectiveness of accident-prevention investments that include only anticipated public safety benefits will underestimate the value of such investments if reductions in power plant damage risk are not included. The analysis also suggests that utility self-interest and the public interest in safety are generally coincident. It is argued that greater use could be made of this self-interest in regulation if the relationship between the NRC and the industry were more cooperative, less adversary in nature

  5. Risk monitors - The State of the Art in their Development and Use at Nuclear Power Plants - Produced on behalf of IAEA and OECD/NEA WGRisk

    International Nuclear Information System (INIS)

    Shepherd, C.H.; Yllera, F.J.; Kaufer, B.; Henneke, D.W.; Gaynor, D.; Sedlak, J.; Evans, M.G.K.; Boneham, P.; Horne, B.; Guymer, P.; Hatfield, M.; Hewitt, J.; Shanley, L.; Sorman, J.; Chao, C.C.; Pullen, R.; Reinhart, F.M.; Lantaron, A.; Huerta, A.; Vojnovic, D.; Hollo, E.; Fukuda, M.; De Gelder, P.; Schulz, R.; Lanore, J.M.

    2004-01-01

    This report provides a description of the state-of-the-art in the development and use of Risk Monitors at nuclear power plants in the Member States. The work has been carried out jointly by IAEA and OECD WGRisk. The information presented in this report has been obtained from three questionnaires on the development and use of Risk Monitors, software and Regulatory perspectives; from OECD and IAEA Workshops on Risk Monitors; and from IAEA consultants meetings and WGRisk Task Group meetings. Some of the work carried out to produce the report has been funded by the United Kingdom Nuclear Installations Inspectorate. The aim is to produce a report that describes the state of the art in the development of Risk Monitors and their use at nuclear power plants. This will: - define the terminology that relates to Risk Monitors as used in this report, - describe the state of the art in the development and use of Risk Monitors at nuclear power plants, and indicate future developments, - provide information on the software packages available for Risk Monitors, - identify the issues that need to be addressed in the development of a Living PSA for use in a Risk Monitor application and give guidance on how these issues can be resolved, - give information on the issues relating to the design of the Risk Monitor operator interface so that it gives a tool that can be used by all station staff, - discuss the issues that relate to the qualitative and quantitative risk measures addressed by Risk Monitors such as the definition of the Operational Safety Criteria which define the risk levels, the calculation of the Allowed Configuration Time and the definition of the qualitative risk levels that relate to the availability of safety systems, - give insights into the costs involved, the benefits that can be obtained from Risk Monitors and their limitations, and - discuss the regulatory perspective on the use of Risk Monitors to provide risk information that can be used during nuclear power

  6. Thermonuclear power plants and the environment

    International Nuclear Information System (INIS)

    Becka, J.

    1978-01-01

    Environmental safety and protection from the effects of the thermonuclear power plants are discussed. Factors are assessed which should be considered in the choice of fuel and breeding material of a thermonuclear reactor, the problems of structural material activation and the overall reactor concepts. Main specifications are given of the US thermonuclear power plant projects with D-T reaction based reactors. The overall amounts of tritium in the reactor cycles are shown. The potential biological risk is evaluated for the different materials considered for the UWMAK-1 project. Discussed are possible pathways of activity release in normal plant operation, non-radioactive aspects, such as waste heat, the magnetic field effect on personnel and population, etc., as well as possible environmental impacts in case of accidents. (B.S.)

  7. Evaluation of Foreign Investment in Power Plants using Real Options

    Science.gov (United States)

    Kato, Moritoshi; Zhou, Yicheng

    This paper proposes new methods for evaluating foreign investment in power plants under market uncertainty using a real options approach. We suppose a thermal power plant project in a deregulated electricity market. One of our proposed methods is that we calculate the cash flow generated by the project in a reference year using actual market data to incorporate periodic characteristics of energy prices into a yearly cash flow model. We make the stochastic yearly cash flow model with the initial value which is the cash flow in the reference year, and certain trend and volatility. Then we calculate the real options value (ROV) of the project which has abandonment options using the yearly cash flow model. Another our proposed method is that we evaluate foreign currency/domestic currency exchange rate risk by representing ROV in foreign currency as yearly pay off and exchanging it to ROV in domestic currency using a stochastic exchange rate model. We analyze the effect of the heat rate and operation and maintenance costs of the power plant on ROV, and evaluate exchange rate risk through numerical examples. Our proposed method will be useful for the risk management of foreign investment in power plants.

  8. Significance of earthquake risk in nuclear power plant probabilistic risk assessments

    International Nuclear Information System (INIS)

    Sues, R.H.; Amico, P.J.; Campbell, R.D.

    1990-01-01

    During the last eight years, approximately 25 utility-sponsored probabilistic risk assessments (PRAs) have been conducted for US nuclear reactors. Of these, ten have been published, seven of which have included complete seismic risk assessment. The results of the seven published PRAs are reviewed here in order to ascertain the significance of the risk due to earthquake initiating events. While PRA methodology has been in a state of development over the past seven years, and the results are subject to interpretation (as discussed in the paper), from the review conducted it is clear that earthquake-induced initiating events are important risk contributors. It is concluded that earthquake initiating events should not be dismissed, a priori, in any nuclear plant risk assessment. (orig.)

  9. Low Power Shutdown PSA for CANDU Type Plants

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Yeon Kyoung; Kim, Myung Su [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    KHNP also have concentrated on full power PSA. Some recently constructed OPR1000 type plants and APR1400 type plants have performed the low power and shutdown (LPSD) PSA. The purpose of LPSD PSA is to identify the main contributors on the accident sequences of core damage and to find the measure of safety improvement. After the Fukushima accident, Korean regulatory agency required the shutdown severe accident management guidelines (SSAMG) development for safety enhancement. For the reliability of SSAMG, KHNP should develop the LPSD PSA. Especially, the LPSD PSA for CANDU type plant had developed for the first time in Korea. This paper illustrates how the LPSD PSA for CANDU type developed and the core damage frequency (CDF) is different with that of full power PSA. KHNP performed LPSD PSA to develop the SSAMG after the Fukushima accidents. The results show that risk at the specific operation mode during outage is higher than that of full power operation. Also, the results indicated that recovery failure of class 4 power at the POS 5A, 5B contribute dominantly to the total CDF from importances analysis. LPSD PSA results such as CDF with initiating events and POSs, risk results with plant damage state, and containment failure probability and frequency with POSs can be used by inputs for developing the SSAMG.

  10. Voltage Feedback based Harmonic Compensation for an Offshore Wind Power Plant

    DEFF Research Database (Denmark)

    Chaudhary, Sanjay K.; Lascu, Cristian; Teodorescu, Remus

    2016-01-01

    When an offshore wind power plant is connected to the grid, there is a risk of amplification of certain harmonics and appearance resonances at the point of connection due to the interaction between the grid network and the wind power plant network. Hence, the plant developer is obliged to maintain...

  11. The Risk Management in New Technology Deployment to Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kil Young; Roh, Myung Sub [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2013-10-15

    This paper figures out that it is required to build the structured and integrated risk management system in enterprise level. By means of it, the accumulated data and experience of work can be shared and transferred effectively among workers, and consequently design mistake or error can be reduced. It has been requested to upgrade and replace equipment in Nuclear Power Plant (NPP) with new technology because of obsolescence and spare parts issues, and demands for higher performance. The processes for the new technology deployment to NPP, however, may have risks causing the unpredictable outcomes leading to the degradation of performance or operation. Therefore, the proper risk management is essential for ensuring safety and performance of NPP since it provides means to identify risks and minimizing their impacts. For these reason, this paper aims at investigating how the risk is managed and presents the proper risk management in project for the deployment of new technology to NPP. This paper investigated how the risk is managed in the NPP industry. Risk is perceived as a negative term that brings negative impact on project objectives. 10 key risks are identified and classified as high risk on cost, time, scope, or quality in compliance with the criteria seeking 'Safety First'. Design mistake or error' can significantly influence three project objectives while the rest risks can significantly influence one or two project objectives. However, it is also found that there are neither structured ways nor a systematical approach to perform the proper risk management. As a result, risk management such as identification, assessment, and response is mostly performed in the individual level laying much weight on experience since the most common methods are past experience and review of similar case.

  12. The Risk Management in New Technology Deployment to Nuclear Power Plant

    International Nuclear Information System (INIS)

    Jung, Kil Young; Roh, Myung Sub

    2013-01-01

    This paper figures out that it is required to build the structured and integrated risk management system in enterprise level. By means of it, the accumulated data and experience of work can be shared and transferred effectively among workers, and consequently design mistake or error can be reduced. It has been requested to upgrade and replace equipment in Nuclear Power Plant (NPP) with new technology because of obsolescence and spare parts issues, and demands for higher performance. The processes for the new technology deployment to NPP, however, may have risks causing the unpredictable outcomes leading to the degradation of performance or operation. Therefore, the proper risk management is essential for ensuring safety and performance of NPP since it provides means to identify risks and minimizing their impacts. For these reason, this paper aims at investigating how the risk is managed and presents the proper risk management in project for the deployment of new technology to NPP. This paper investigated how the risk is managed in the NPP industry. Risk is perceived as a negative term that brings negative impact on project objectives. 10 key risks are identified and classified as high risk on cost, time, scope, or quality in compliance with the criteria seeking 'Safety First'. Design mistake or error' can significantly influence three project objectives while the rest risks can significantly influence one or two project objectives. However, it is also found that there are neither structured ways nor a systematical approach to perform the proper risk management. As a result, risk management such as identification, assessment, and response is mostly performed in the individual level laying much weight on experience since the most common methods are past experience and review of similar case

  13. Risk based optimization of technical specifications for operation of nuclear power plants

    International Nuclear Information System (INIS)

    1993-12-01

    The objective of the report is to present an overview of the risk and reliability based approaches (using a probabilistic safety assessment (PSA)) for improving nuclear power plant technical specifications (TS). In that case, it will provide an information base to the Member States in seeking PSA based applications to enhance the effectiveness of their technical specifications. To achieve this objective, the report discusses the basic objectives and reasons for seeking TS changes, the methods, data requirements and uses of different types of applications, and an overview of different applications that have been completed, including detailed descriptions of selected applications. Refs, figs and tabs

  14. I and C upgrading at nuclear power plants

    International Nuclear Information System (INIS)

    Tamiri, A.

    2003-01-01

    Continuing the operation of existing nuclear power plants will help reduce the number of new base-load nuclear and fossil power plants that need to be built. Old nuclear power plants in Canada are operating with analog instrumentation and control systems. For a number of reasons, such as changes and improvements in the applicable standards and design, maintenance problems due to the lack of spares, technical obsolescence, the need to increase power production, availability, reliability and safety, and in order to reduce operation and maintenance costs, instrumentation and control upgrading at nuclear power plants in a cost effective manner should be considered the greatest priority. Failures of instrumentation and control (I and C) due to aging and obsolescence issues may have an immediate negative impact on plant reliability and availability and also affect long-term plant performance and safety. In today's competitive marketplace, power plants are under pressure to cut spending on maintenance while reducing the risk of equipment failure that could cause unplanned outage. To improve plant safety and availability, old nuclear power plants will require investment in new technologies that can improve the performance and reduce the costs of generation by addressing the long term reliability of systems by up-grading to modem digital instrumentation and control and optimization opportunities. Boiler drum level control at nuclear power plants is critical for both plant protection and equipment safety and applies equality to high and low levels of water within the boiler drum. Plant outage studies at Pickering Nuclear have identified boiler drum level control and feed water control systems as major contributors to plant unavailability. Ways to improve transient and steady state response, upgrading existing poor analog control systems for boiler level and feed-water control systems at Pickering Nuclear, with enhanced and robust controller will be discussed in this paper

  15. Emergency response and nuclear risk governance. Nuclear safety at nuclear power plant accidents

    International Nuclear Information System (INIS)

    Kuhlen, Johannes

    2014-01-01

    The present study entitled ''Emergency Response and Nuclear Risk Governance: nuclear safety at nuclear power plant accidents'' deals with issues of the protection of the population and the environment against hazardous radiation (the hazards of nuclear energy) and the harmful effects of radioactivity during nuclear power plant accidents. The aim of this study is to contribute to both the identification and remediation of shortcomings and deficits in the management of severe nuclear accidents like those that occurred at Chernobyl in 1986 and at Fukushima in 2011 as well as to the improvement and harmonization of plans and measures taken on an international level in nuclear emergency management. This thesis is divided into a theoretical part and an empirical part. The theoretical part focuses on embedding the subject in a specifically global governance concept, which includes, as far as Nuclear Risk Governance is concerned, the global governance of nuclear risks. Due to their characteristic features the following governance concepts can be assigned to these risks: Nuclear Safety Governance is related to safety, Nuclear Security Governance to security and NonProliferation Governance to safeguards. The subject of investigation of the present study is as a special case of the Nuclear Safety Governance, the Nuclear Emergency governance, which refers to off-site emergency response. The global impact of nuclear accidents and the concepts of security, safety culture and residual risk are contemplated in this context. The findings (accident sequences, their consequences and implications) from the analyses of two reactor accidents prior to Fukushima (Three Mile Iceland in 1979, Chernobyl in 1986) are examined from a historical analytical perspective and the state of the Nuclear Emergency governance and international cooperation aimed at improving nuclear safety after Chernobyl is portrayed by discussing, among other topics, examples of &apos

  16. Man as a protective barrier in nuclear power plants

    International Nuclear Information System (INIS)

    Fechner, J.B.

    1980-01-01

    Evaluation of nuclear power plant incidents frequently reveals man as a major element of risk. Yet, in a nuclear power plant man has the function of an important protective barrier, either by maintaining the plant, by detecting and limiting faults or incidents, or by taking proper measures in accidents. This is true despite, or perhaps because of, the high degree of plant automation. For this reason, it is indispensable that a high level of engineered plant safeguards be accompanied by a minimum of faults contributed by human action. This implies that the staff and their working conditions must meet the same stringent safety requirements as the nuclear power plant proper. Reactor manufacturers, nuclear power plant operators and the responsible authorities try to optimize this human contribution. The Federal Ministry of the Interior, through its Special Technical Guidelines and its continuation training measures, occupies an important position in this respect. Further measures and ordinances are being prepared by that Ministry. (orig.) [de

  17. Safety goals for nuclear power plants: a discussion paper

    International Nuclear Information System (INIS)

    1982-02-01

    This report includes a proposed policy statement on safety goals for nuclear power plants published by the Commission for public comment and a supporting discussion paper. Proposed qualitative goals and associated numerical guidelines for nuclear power-plant accident risks are presented. The significance of the goals and guidelines, their bases and rationale, and their proposed mode of implementation are discussed

  18. Radiation risk analysis of tritium in PWR plants

    International Nuclear Information System (INIS)

    Yang Maochun; Wang Shimin

    1999-03-01

    Tritium is a common radionuclide in PWR nuclear power plant. In the normal operation conditions, its radiation risk to plant workers is the internal radiation exposure when tritium existing in air as HTO (hydrogen tritium oxide) is breathed in. As the HTO has the same physical and chemical characteristics as water, the main way that HTO entering the air is by evaporation. There are few opening systems in Nuclear Power Plant, the radiation risk of tritium mainly exists near the area of spent fuel pit and reactor pit. The highest possible radiation risk it may cause--the maximum concentration in air is the level when equilibrium is established between water and air phases for tritium. The author analyzed the relationship among the concentration of HTO in water, in air and the water temperature when equilibrium is established, the equilibrated HTO concentration in air increases with HTO concentration in water and water temperature. The analysis revealed that at 30 degree C, the equilibrated HTO concentration in air might reach 1 DAC (derived air concentration) when the HTO concentration in water is 28 GBq/m 3 . Owing to the operation of plant ventilation systems and the existence of moisture in the input air of the ventilation, the practical tritium concentration in air is much lower than its equilibrated levels, the radiation risk of tritium in PWR plant is quite limited. In 1997, Daya Bay Nuclear Power Plant's practical monitoring result of the HTO concentration in the air of the nuclear island and the urine of workers supported this conclusion. Based on this analysis, some suggestions to the reduction of tritium radiation risk were made

  19. Probabilistic evaluation of risks associated with aviation, road, railway and river traffic adjacent to nuclear power plants in France

    International Nuclear Information System (INIS)

    Procaccia, H.; Gobert, T.

    1978-01-01

    Electricite de France has developed a methodology to calculate the potential impact of risks to a nuclear power plant subsequent to an accident occurring on transportation networks in the vicinity of a nuclear site. Risks entailed in aviation, and in road, rail, and river traffic have been estimated. This methodology has been applied to all sites planned in France

  20. FIRE SAFETY IN NUCLEAR POWER PLANTS: A RISK-INFORMED AND PERFORMANCE-BASED APPROACH

    Energy Technology Data Exchange (ETDEWEB)

    AZARM,M.A.; TRAVIS,R.J.

    1999-11-14

    The consideration of risk in regulatory decision-making has long been a part of NRC's policy and practice. Initially, these considerations were qualitative and were based on risk insights. The early regulations relied on good practices, past insights, and accepted standards. As a result, most NRC regulations were prescriptive and were applied uniformly to all areas within the regulatory scope. Risk technology is changing regulations by prioritizing the areas within regulatory scope based on risk, thereby focusing on the risk-important areas. Performance technology, on the other hand, is changing the regulations by allowing requirements to be adjusted based on the specific performance expected and manifested, rather than a prior prescriptive requirement. Consistent with the objectives of risk-informed and performance-based regulatory requirements, BNL evaluated the feasibility of applying risk- and performance-technologies to modifying NRC's current regulations on fire protection for nuclear power plants. This feasibility study entailed several case studies (trial applications). This paper describes the results of two of them. Besides the case studies, the paper discusses an overall evaluation of methodologies for fire-risk analysis to support the risk-informed regulation. It identifies some current shortcomings and proposes some near-term solutions.

  1. Financing Solar Thermal Power Plants

    International Nuclear Information System (INIS)

    Price, Henry W.; Kistner, Rainer

    1999-01-01

    The commercialization of concentrating solar power technology took a major step forward in the mid 1980s and early 1990s with the development of the SEGS plants in California. Over the years they have proven that parabolic trough power technologies are the most cost-effective approach for commercial scale solar power generation in the sunbelt countries of the world. However, the question must be asked why no additional solar power plants have been build following the bankruptcy of the developer of the SEGS projects, LUZ International Limited. Although many believe the SEGS projects were a success as a result of parabolic trough technology they employ, in truth, the SEGS projects were developed simply because they represented an attractive opportunity for investors. Simply stated, no additional projects have been developed because no one has been able to put together a similarly attractive financial package to potential investors. More than $1.2 billion in private capital was raised in debt and equity financing for the nine SEGS plants. Investors and bankers who make these investments are the real clients for solar power technologies. They are not interested in annual solar to electric efficiencies, but in risk, return on investments, and coverage ratios. This paper will take a look at solar power projects from the financier's perspective. The challenge in moving forward is to attract private investors, commercial lenders, and international development agencies and to find innovative solutions to the difficult issues that investment in the global power market poses for solar power technologies

  2. Financing solar thermal power plants

    International Nuclear Information System (INIS)

    Kistner, R.; Price, H.

    1999-01-01

    The commercialization of concentrating solar power technology took a major step forward in the mid 1980s and early 1990s with the development of the SEGS plants in California. Over the years they have proven that parabolic trough power technologies are the most cost-effective approach for commercial scale solar power generation in the sunbelt countries of the world. However, the question must be asked why no additional solar power plants have been built following the bankruptcy of the developer of the SEGS projects, LUZ International Limited. Although many believe the SEGS projects were a success as a result of parabolic trough technology they employ, in truth, the SEGS projects were developed simply because they represented an attractive opportunity for investors. Simply states, no additional projects have been developed because no one has been able to put together a similarly attractive financial package to potential investors. More than $1.2 billion in private capital was raised in debt and equity financing for the nine SEGS plants. Investors and bankers who make these investments are the real clients for solar power technologies. They are not interested in annual solar to electric efficiencies, but in risk, return on investments, and coverage ratios. This paper will take a look at solar power projects form the financier's perspective. The challenge in moving forward is to attract private investors, commercial lenders, and international development agencies and to find innovative solutions to the difficult issues that investment in the global power market poses for solar power technologies

  3. Financing Solar Thermal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Kistner, Rainer [National Renewable Energy Lab. (NREL), Golden, CO (United States); Price, Henry W. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    1999-04-14

    The commercialization of concentrating solar power technology took a major step forward in the mid 1980s and early 1990s with the development of the SEGS plants in California. Over the years they have proven that parabolic trough power technologies are the most cost-effective approach for commercial scale solar power generation in the sunbelt countries of the world. However, the question must be asked why no additional solar power plants have been build following the bankruptcy of the developer of the SEGS projects, LUZ International Limited. Although many believe the SEGS projects were a success as a result of parabolic trough technology they employ, in truth, the SEGS projects were developed simply because they represented an attractive opportunity for investors. Simply stated, no additional projects have been developed because no one has been able to put together a similarly attractive financial package to potential investors. More than $1.2 billion in private capital was raised in debt and equity financing for the nine SEGS plants. Investors and bankers who make these investments are the real clients for solar power technologies. They are not interested in annual solar to electric efficiencies, but in risk, return on investments, and coverage ratios. This paper will take a look at solar power projects from the financier’s perspective. The challenge in moving forward is to attract private investors, commercial lenders, and international development agencies and to find innovative solutions to the difficult issues that investment in the global power market poses for solar power technologies.

  4. Childhood leukaemia incidence below the age of 5 years near French nuclear power plants

    International Nuclear Information System (INIS)

    Laurier, D; Hemon, D; Clavel, J

    2008-01-01

    A recent study indicated an excess risk of leukaemia among children under the age of 5 years living in the vicinity of nuclear power plants in Germany. We present results relating to the incidence of childhood leukaemia in the vicinity of nuclear power plants in France for the same age range. These results do not indicate an excess risk of leukaemia in young children living near French nuclear power plants. (note)

  5. Analysis of the Relationship between Risk Perception and Willingness to Pay for Nuclear Power Plant Risk Reduction

    Directory of Open Access Journals (Sweden)

    Mirae Yun

    2016-01-01

    Full Text Available With the adoption of new technologies, more risk is introduced into modern society. Important decisions about new technologies tend to be made by specialists, which can lead to a mismatch of risk perception between citizens and specialists, resulting in high social cost. Using contingent valuation methods, this paper analyzes the relationship between willingness to pay (WTP and the factors expressed through people’s image of nuclear power plants (NPP, their perception of NPP safety, and how these can be affected by their scientific background level. Results indicate that groups with a high scientific background level tend to have low risk perception level, represented through their image and safety levels. Further, the results show that mean WTP is dependent on scientific background and image levels. It is believed that these results could help decision makers address the mismatch of trust between the public and specialists in terms of new policy.

  6. The challenge of financing nuclear power plants

    International Nuclear Information System (INIS)

    Csik, B.J.

    1999-01-01

    To date, more then 500 nuclear power reactors have been successfully financed and built. Experience in recent nuclear projects confirms that nuclear power will not cease to be a viable option due to a worldwide financing constraint. For financing nuclear plants there are special considerations: large investment; long lead and construction times; complex technology; regulatory risk and political risk. The principal preconditions to financing are a national policy supporting nuclear power; creditworthiness; economic competitiveness; project feasibility; assurance of adequate revenues; acceptability of risks; and no open-ended liabilities. Generally, nuclear power plants are financed conventionally through multi-sources, where a package covers the entire cost. The first source, the investor/owner/operator responsible for building and operating the plant, should cover a sizable portion of the overall investment. In addition, bond issues, domestic bank credits etc. and, in case of State-owned or controlled enterprises, donations and credits from public entities or the governmental budget, should complete the financing. A financially sound utility should be able to meet this challenge. For importing technology, bids are invited. Export credits should form the basis of foreign financing, because these have favorable terms and conditions. Suppliers from several countries may join in a consortium subdividing the scope of supply and involve several Export Credit Agencies (ECAs). There are also innovative financing approaches that could be applied to nuclear projects. Evolutionary Reactors with smaller overall investment, shorter construction times, reliance on proven technology, together with predictable regulatory regimes and reliable long-term national policies favorable to nuclear power, should make it easier to meet the future challenges of financing. (author)

  7. A comparative thermodynamic, economic and risk analysis concerning implementation of oxy-combustion power plants integrated with cryogenic and hybrid air separation units

    International Nuclear Information System (INIS)

    Skorek-Osikowska, Anna; Bartela, Łukasz; Kotowicz, Janusz

    2015-01-01

    Highlights: • Mathematical model of an integrated oxy-combustion power plant. • Comparison of a hybrid membrane–cryogenic oxygen generation plant with a cryogenic plant. • Thermodynamic analysis of the modeled cases of the plant. • Comparative economic analysis of the power plant with cryogenic and hybrid ASU. • Comparative risk analysis using a Monte Carlo method and sensitivity analysis. - Abstract: This paper presents a comparison of two types of oxy-combustion power plant that differ from each other in terms of the method of oxygen separation. For the purpose of the analysis, detailed thermodynamic models of oxy-fuel power plants with gross power of approximately 460 MW were built. In the first variant (Case 1), the plant is integrated with a cryogenic air separation unit (ASU). In the second variant (Case 2), the plant is integrated with a hybrid membrane–cryogenic installation. The models were built and optimized using the GateCycle, Aspen Plus and Aspen Custom Modeller software packages and with the use of our own computational codes. The results of the thermodynamic evaluation of the systems, which primarily uses indicators such as the auxiliary power and efficiencies of the whole system and of the individual components that constitute the unit, are presented. Better plant performance is observed for Case 2, which has a net efficiency of electricity generation that is 1.1 percentage points greater than that of Case 1. For the selected structure of the system, an economic analysis of the solutions was made. This analysis accounts for different scenarios of the functioning of the Emission Trading Scheme and includes detailed estimates of the investment costs in both cases. As an indicator of profitability, the break-even price of electricity was used primarily. The results of the analysis for the assumptions made are presented in this paper. A system with a hybrid air separation unit has slightly better economic performance. The break-even price

  8. Nuclear power plant's safety and risk (requirements of safety and reliability)

    International Nuclear Information System (INIS)

    Franzen, L.F.

    1977-01-01

    Starting out from the given safety objectives as they have evolved during the past few years and from the present legal and regulatory provisions for the construction and operation of nuclear power plants, the hazards involved in regular operation, accidents and emergency situations are discussed. In compliance with the positive safety balance of nuclear power plants in the FRG, special attention is focused on the preventive safety analysis within the frame of the nuclear licensing procedure. Reference is made to the beginnings of a comprehensive hazard concept for an unbiased plant assessment. Emergency situations are discussed from the point of view of general hazard comparisons. (orig.) [de

  9. Losses in German nuclear power plants

    International Nuclear Information System (INIS)

    Abinger, R.

    1982-01-01

    The author illustrates the special features of engineering insurance for nuclear power plants. The shares of the Allianz Versicherungs-AG in the insurance of construction and erection work and in machinery insurance are dealt with. Risk estimation is usually based on statistical analysis of losses. Loss analysis in the conventional sector of nuclear power plants shows typical characteristics of traditional erection and machinery losses. In the nuclear field, however, costs are greatly increased by added safety measures. For this reason, additional cover is allocated and incorporated in premium assessment. Examples from erection and machinery reveal the greater costs involved in handling losses. (orig.) [de

  10. Cancer incidence in the environment of nuclear power plants

    International Nuclear Information System (INIS)

    Heller, W.

    2008-01-01

    An epidemiological study of cancer in children in the environment of nuclear power plants has been written on behalf of the German Federal Ministry for the Environment, Nature Conservation, and Nuclear Safety (BMU) and the Federal Office for Radiation Protection (BfS). The study is a case controlled study based on the German Register of Cancer in Children. The most important outcome of the study is the finding that a connection can be observed in Germany between the proximity to a nuclear power plant of the place of living and the risk of a child to develop cancer in the 5 th year of life. The magnitude of this risk was calculated to be approximately 0.2%, i.e., out of a total of 13,373 cases of cancer, 29 would be attributable to living within the 5 km zone around a nuclear power plant. This finding demands an explanation. The study proper cannot serve as a material witness because it had not been designed to establish cause and effect relations between the risk and potential origins. The expert consultants frankly state that current knowledge about radiation biology and epidemiology in principle does not allow the ionizing radiation emitted by German nuclear power plants in normal operation to be interpreted as the cause. Whether confounders, selection or chance play a role in the observed and documented finding cannot be explained for good by the study. However, although representing an honorable acquittal, the study produces a different effect in the public mind. What is remembered is the link between nuclear power plants and cancer in children. (orig.)

  11. Nuclear plant construction and investment risk

    International Nuclear Information System (INIS)

    Studness, C.M.

    1984-01-01

    Escalated cost estimations, delays and cancellations in nuclear construction have caused a preoccupation with the risks of nuclear power plant construction that dominates utility stock investment, overshadowing increased earnings per share and recent growth in production. The issue will be resolved when increased power demand requires new construction, but the effect has so far been to erode the economic advantage of nuclear power and threaten the ability of utilities to get rate increases high enough to cover their costs. Projected delays and cost escalations and their effects must go into an economic appraisal of the investment risks

  12. Best practices for mitigating soiling risk on PV power plants

    KAUST Repository

    AlDowsari, A.

    2015-09-24

    Solar power generates proven, predictable and economical energy and new innovations have made solar PV power plants easy to deploy, integrate and maintain. Areas with large solar energy potential are among the dustiest in the world. At first glance, solar would be a natural fit in many of these environments but humidity, airborne dust, and wind of these regions often bring high soiling rates that can accumulate to reduce performance by up to 10% per month on average, where soiling can be a major loss factor that affects the energy yield for PV plants especially in humid and dusty climates. Therefore, to achieve the desired performance ratio and obtain stable generation, mitigation solutions are proposed to overcome dust issues that affect the performance of PV plants. This makes PV module cleaning a key component for long-term plant performance and sustainable profitability. In this paper, a review of the mechanisms and mitigation solutions to overcome soiling on solar installations using real-world testing and verification is investigated with emphasis on dry type cleaning methods. © 2014 IEEE.

  13. Risk-based safety performance indicators for nuclear power plants

    International Nuclear Information System (INIS)

    Chakraborty, S.; Prohaska, G.; Flodin, Y.; Grint, G.; Habermacher, H.; Hallman, A.; Isasia, R.; Melendez, E.; Verduras, E.; Karsa, Z.; Khatib-Rahbar, M.; Koeberlein, K.; Schwaeger, C.; Matahri, N.; Moravcik, I.; Tkac, M.; Preston, J.

    2003-01-01

    In a Concerted Action (CA), sponsored by the European Commission within its 5th Framework Program, a consortium of eleven partners from eight countries has reviewed and evaluated the application of Safety Performance Indicators (SPIs), which - in combination with other tools - can be used to monitor and improve the safety of nuclear power plants. The project was aimed at identification of methods that can be used in a risk-informed regulatory system and environment, and to exploit PSA techniques for the development and use of meaningful additional/alternative SPIs. The CA included the review of existing indicator systems, and the collection of information on the experience from indicator systems by means of a specific questionnaire. One of the most important and challenging issues for nuclear plant owners and/or regulators is to recognize early signs of deterioration in safety performance, caused by influences from management, organization and safety culture (MOSC), before actual events and/or mishaps take place. Most of the existing SPIs as proposed by various organizations are considered as 'lagging' indicators, that is, they are expected to show an impact only when a downward trend has already started. Furthermore, most of the available indicators are at a relatively high level, such that they will not provide useful information on fundamental weaknesses causing the problem in the first place. Regulators' and utilities' views on the use of a Safety Performance Indicator System have also been a part of the development of the CA. (author)

  14. Requirements for the support power systems of CANDU nuclear power plants

    International Nuclear Information System (INIS)

    1990-08-01

    This Standard covers principal criteria and requirements for design, fabrication, installation, qualification, inspection, and documentation for assurance that support power will be available as required. The minimum requirements for support power are determined by the special safety systems and other safety-related systems that must function to ensure that the public health risk is acceptably low. Support power systems of a CANDU nuclear power plant include those parts of the electrical systems and instrument air systems that are necessary for the operation of safety-related systems

  15. TEPCO's costs and risks which invited the nuclear power plant accident

    International Nuclear Information System (INIS)

    Soeda, Takashi

    2017-01-01

    The National Diet of Japan Fukushima Nuclear Accident Independent Investigation Commission (Diet Accident Investigation Commission) considered two patterns against the tsunami risk of nuclear plant: (1) Risk management for the purpose of safety (Pattern A), and (2) Risk management for the purpose of utilization rate and cost of nuclear reactor (Pattern B). Pattern B emphasizes avoiding 'countermeasure cost generation' and 'operation shutdown' rather than preparing for a tsunami that we do not know when to come. Diet Accident Investigation Commission analyzed that the behavioral principles concerning the crisis response of Tokyo Electric Power Company (TEPCO) had the stronger tendency of Pattern B. Regarding the accident of TEPCO, there were class actions that asked the responsibility of TEPCO and the government. This paper examined the contents of the opinions of government-side experts submitted for this issue. The government-side experts argued that there was no 'scientific consensus' for tsunami forecast, and that preliminary measures against unexpected tsunami was impossible. However, both of these government's arguments are irrational due to difference from the fact. TEPCO president at the time of accident insisted in the firm that 'cost cut in another dimension' was indispensable and reduced expenses. TEPCO and the government had continued Pattern B, even knowing that tsunami risk measures were insufficient from more than ten years ago. (A.O.)

  16. A method for risk informing procedures at operating nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, P. F.; Martin del Campo, C., E-mail: pnelson_007@yahoo.com [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Paseo Cuauhnahuac No. 8532, Col. Progreso, 62550 Jiutepec, Morelos (Mexico)

    2012-10-15

    The technical approach presented establishes a framework intended to provide the necessary elements for a deployable human performance monitoring program that incorporates insights from plant specific probabilistic risk assessments, human reliability analysis, as well as the development of plant specific human failure data. A human performance monitoring program of this structure would be used to provide the ability to risk inform procedures (e.g., operations or maintenance) to determine the operational risk significance of procedural performance (i.e., precautions, prerequisites, procedure steps), the likelihood of consequential human error dur the performance of the procedure, and the identification of procedure specific barriers to reduce or eliminate consequential human errors. The program would provide the means to assess procedures prior to execution and the means to record and trend human failure events leading to a plant specific human failure database for human activities characterized as pre-initiator. The technical methods and data processing for each of these areas are developed and presented, as well as an example application of an operational procedure error leading to a plant level event (i.e, plant trip). (Author)

  17. Less power plants

    International Nuclear Information System (INIS)

    TASR

    2003-01-01

    In the Slovak Republic the number of company power plants decreased as against 2001 by two sources. In present time only 35 companies have their own power plants. The companies Slovnaft, Kappa Sturovo, Slovensky hodvab Senica, Matador Puchov, Maytex Liptovsky MikuIas, Kovohuty Krompachy, Chemko Strazske and some Slovak sugar factories belong to the largest company power plants in force of distributing companies. Installed output of present 35 company sources is 531 MW. The largest of separate power plants as Paroplynovy cyklus Bratislava (218 MW) and VD Zilina (72 MW) belong to independent sources. Total installed output of Slovak sources was 8306 MW in the end of last year

  18. Protection against fire hazards in French nuclear power plants

    International Nuclear Information System (INIS)

    Chapus, J.

    2000-01-01

    The prevention of fire in French nuclear power plants has followed the evolution of safety regulations. Today fire hazards are no longer considered as classical industrial risks but as specific risks that deserve to be studied thoroughly and in a more formalized form. In the beginning of the eighties EDF was committed to the redaction of a technical referential against fire gathering all the directives applicable to the N4-type plant (1450 MW). In 1994 this technical referential was reconsidered and enlarged in order to involve 900 MW and 1300 MW units. In each nuclear power plant a PAI (plan against fire) has been elaborated so that the installation can be progressively upgraded according to the last standard defined by the technical referential. (A.C.)

  19. The problem of nuclear power plants site survey and selection

    International Nuclear Information System (INIS)

    Anh, T.H.; Hung, H.V.; Bui Quoc Thang

    1986-01-01

    The article presents the main steps of nuclear power plants siting, including the requirements from a nuclear power station onto the site, and the analysis of potential effects of a nuclear power station to the environment. Attentions are called upon the analysis of important factors such as electric transmission losses, cooling water supply, site accessibility, local infrastructure, risks due to man made and natural sources of aggression to the nuclear power plants, population, distribution, hydrological and atmospheric dispersion conditions

  20. 'Living PRA' concept for plant risk: Reliability and availability tracking

    International Nuclear Information System (INIS)

    Sancaktar, S.; Sharp, D.R.

    1985-01-01

    The 'Living PRA' (Probabilistic Risk Assessment) is based on placing a PRA plant model on an interactive computer. This model consists of fault tree analyses for plant systems, event tree analyses for abnormal events and site specific consequence analysis for public and/or financial risks, for a nuclear power plant. A living PRA allows updates and sensitivity analyses by the plant owner throughout the lifetime of a plant. Recently, event and fault trees from two major PRAs were placed in a computerized format. The BYRON PRA study and the Living PRA and Economic Risk examples for Indian Point Unit-3 enabled analysts to gain experience and insight into the problems of plant operation. The above concept is well established for the Nuclear Power Plant evaluation. It has been also used for evaluation of processing facilities. In these studies, systems modeling was carried out by using the GRAFTER system for automated fault tree construction. Presently both the tools and the experience exists to set up useful and viable living PRA models for nuclear and chemical processing plants to enhance risk management by the plant owners through in-house use of micro computer based models

  1. Feasibility study of component risk ranking for plant maintenance

    International Nuclear Information System (INIS)

    Ushijima, Koji; Yonebayashi, Kenji; Narumiya, Yoshiyuki; Sakata, Kaoru; Kumano, Tetsuji

    1999-01-01

    Nuclear power is the base load electricity source in Japan, and reduction of operation and maintenance cost maintaining or improving plant safety is one of the major issues. Recently, Risk Informed Management (RIM) is focused as a solution. In this paper, the outline regarding feasibility study of component risk ranking for plant maintenance for a typical Japanese PWR plant is described. A feasibility study of component risk raking for plant maintenance optimization is performed on check valves and motor-operated valves. Risk ranking is performed in two steps using probabilistic analysis (quantitative method) for risk ranking of components, and deterministic examination (qualitative method) for component review. In this study, plant components are ranked from the viewpoint of plant safety / reliability, and the applicability for maintenance is assessed. As a result, distribution of maintenance resources using risk ranking is considered effective. (author)

  2. Predicting the environmental risks of radioactive discharges from Belgian nuclear power plants

    International Nuclear Information System (INIS)

    Vandenhove, H.; Sweeck, L.; Vives i Batlle, J.; Wannijn, J.; Van Hees, M.; Camps, J.; Olyslaegers, G.; Miliche, C.; Lance, B.

    2013-01-01

    An environmental risk assessment (ERA) was performed to evaluate the impact on non-human biota from liquid and atmospheric radioactive discharges by the Belgian Nuclear Power Plants (NPP) of Doel and Tihange. For both sites, characterisation of the source term and wildlife population around the NPPs was provided, whereupon the selection of reference organisms and the general approach taken for the environmental risk assessment was established. A deterministic risk assessment for aquatic and terrestrial ecosystems was performed using the ERICA assessment tool and applying the ERICA screening value of 10 μGy h −1 . The study was performed for the radioactive discharge limits and for the actual releases (maxima and averages over the period 1999–2008 or 2000–2009). It is concluded that the current discharge limits for the Belgian NPPs considered do not result in significant risks to the aquatic and terrestrial environment and that the actual discharges, which are a fraction of the release limits, are unlikely to harm the environment. -- Highlights: • Impact of radioactive discharges by the Belgian NPPs of Doel and Tihange on wildlife was evaluated. • Deterministic risk assessment for aquatic and terrestrial ecosystems performed with the ERICA tool. • NPP discharge limits do not result in significant risks to the aquatic and terrestrial environment. • Actual discharges, a fraction of the release limits, are unlikely to harm the environment

  3. Six sigma management and its application in nuclear power plant

    International Nuclear Information System (INIS)

    Liu Weihua; Tong Lili

    2007-01-01

    Six sigma management mode is presented. The feasibility, necessity and the steps to extend six sigma in nuclear power plant are addressed. Nuclear power plant can eliminate or decrease human errors through importing six management concept, the 'zero disfigurement' quality and operation can achieved, decreasing accident risk and realizing safety operation. (authors)

  4. Research on risk communication after the Fukushima nuclear power plant accident

    International Nuclear Information System (INIS)

    Horiguchi, Itsuko

    2013-01-01

    This report is about the risk communication cases that the author participated in after the Fukushima nuclear power plant accident. The research aims to clarify the content of information that should be provided in risk communication and to develop a risk communication tool specifically designed for this purpose. The risk communication cases were explanatory meetings intended for the residents in Fukushima Prefecture and the advisory council on radiation health effects sponsored by Tochigi Prefecture. To clarify the kinds of information necessary to provide at such meetings, we conducted a questionnaire survey of 31 food sanitation inspectors using the Delphi method. A gaming simulation was used for the development of the communication tool. We used public disclosure materials at the meetings and the survey was conducted only among those whom we obtained written informed consent. The content regarding the radioactive substances in food which was found to be the most important for the consumers to learn was ''zero risk is impossible'' (84 points), followed by ''radioactive substances and other risks (e.g. smoking and excessive alcohol intake)'' (70 points). To develop the communication tool, we used ''Quartetto (card game)'' and the contents were such as ''daily life'', ''radioactive substances'', and ''measurement''. Considering the questions raised from the residents at the meetings, an information portal such as homepages did not provide clear information on how to evaluate risks by themselves. The results from the questionnaire survey shows that it is difficult to solve this matter unless the public learns to think about the risks of various matters on their own. The lack of experts will make it necessary for the local government officials to provide more information, and therefore training on risk communication is essential. We need to evaluate the Quartetto game and revise the content considering the audience. (author)

  5. Nuclear Energy Research Initiative. Risk Informed Assessment of Regulatory and Design Requirements for Future Nuclear Power Plants. Annual Report

    International Nuclear Information System (INIS)

    Ritterbusch, S.E.

    2000-01-01

    The overall goal of this research project is to support innovation in new nuclear power plant designs. This project is examining the implications, for future reactors and future safety regulation, of utilizing a new risk-informed regulatory system as a replacement for the current system. This innovation will be made possible through development of a scientific, highly risk-informed approach for the design and regulation of nuclear power plants. This approach will include the development and.lor confirmation of corresponding regulatory requirements and industry standards. The major impediment to long term competitiveness of new nuclear plants in the U.S. is the capital cost component--which may need to be reduced on the order of 35% to 40% for Advanced Light Water Reactors (ALWRs) such as System 80+ and Advanced Boiling Water Reactor (ABWR). The required cost reduction for an ALWR such as AP600 or AP1000 would be expected to be less. Such reductions in capital cost will require a fundamental reevaluation of the industry standards and regulatory bases under which nuclear plants are designed and licensed. Fortunately, there is now an increasing awareness that many of the existing regulatory requirements and industry standards are not significantly contributing to safety and reliability and, therefore, are unnecessarily adding to nuclear plant costs. Not only does this degrade the economic competitiveness of nuclear energy, it results in unnecessary costs to the American electricity consumer. While addressing these concerns, this research project will be coordinated with current efforts of industry and NRC to develop risk-informed, performance-based regulations that affect the operation of the existing nuclear plants; however, this project will go farther by focusing on the design of new plants

  6. Nuclear Energy Research Initiative. Risk Informed Assessment of Regulatory and Design Requirements for Future Nuclear Power Plants. Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Ritterbusch, S.E.

    2000-08-01

    The overall goal of this research project is to support innovation in new nuclear power plant designs. This project is examining the implications, for future reactors and future safety regulation, of utilizing a new risk-informed regulatory system as a replacement for the current system. This innovation will be made possible through development of a scientific, highly risk-informed approach for the design and regulation of nuclear power plants. This approach will include the development and.lor confirmation of corresponding regulatory requirements and industry standards. The major impediment to long term competitiveness of new nuclear plants in the U.S. is the capital cost component--which may need to be reduced on the order of 35% to 40% for Advanced Light Water Reactors (ALWRs) such as System 80+ and Advanced Boiling Water Reactor (ABWR). The required cost reduction for an ALWR such as AP600 or AP1000 would be expected to be less. Such reductions in capital cost will require a fundamental reevaluation of the industry standards and regulatory bases under which nuclear plants are designed and licensed. Fortunately, there is now an increasing awareness that many of the existing regulatory requirements and industry standards are not significantly contributing to safety and reliability and, therefore, are unnecessarily adding to nuclear plant costs. Not only does this degrade the economic competitiveness of nuclear energy, it results in unnecessary costs to the American electricity consumer. While addressing these concerns, this research project will be coordinated with current efforts of industry and NRC to develop risk-informed, performance-based regulations that affect the operation of the existing nuclear plants; however, this project will go farther by focusing on the design of new plants.

  7. A probabilistic seismic risk assessment procedure for nuclear power plants: (I) Methodology

    Science.gov (United States)

    Huang, Y.-N.; Whittaker, A.S.; Luco, N.

    2011-01-01

    A new procedure for probabilistic seismic risk assessment of nuclear power plants (NPPs) is proposed. This procedure modifies the current procedures using tools developed recently for performance-based earthquake engineering of buildings. The proposed procedure uses (a) response-based fragility curves to represent the capacity of structural and nonstructural components of NPPs, (b) nonlinear response-history analysis to characterize the demands on those components, and (c) Monte Carlo simulations to determine the damage state of the components. The use of response-rather than ground-motion-based fragility curves enables the curves to be independent of seismic hazard and closely related to component capacity. The use of Monte Carlo procedure enables the correlation in the responses of components to be directly included in the risk assessment. An example of the methodology is presented in a companion paper to demonstrate its use and provide the technical basis for aspects of the methodology. ?? 2011 Published by Elsevier B.V.

  8. Upgrading Atucha 1 nuclear power plant. Regulatory perspective

    International Nuclear Information System (INIS)

    Caruso, G.

    1998-01-01

    Atucha 1 nuclear power plant has unique design and its commercial operation started in 1974. The upgrading decisions, the basis for an upgrading program and its status of implementation are presented. Regulatory decisions derived from the performance-based approach have the advantage that they enable balancing of the overall plant risk and identifying at different plant levels the areas where improvements are necessary. (author)

  9. Application of the SSMRP methodology to the seismic risk at the Zion Nuclear Power Plant

    International Nuclear Information System (INIS)

    Bohn, M.P.; Shieh, L.C.; Wells, J.E.

    1983-11-01

    The Seismic Safety Margins Research Program (SSMRP) has the goal of developing a fully coupled analysis procedure for estimating the risk of an earthquake-induced radioactive release from a commercial nuclear power plant. The risk analysis included a detailed seismological evaluation of the region around Zion, Illinois, which provided the earthquake-hazard function and a randomized set of 180 time histories (having peak ground acceleration values up to 1.8 g). These time histories were used as input for dynamic structural response calculations for four different Zion buildings. Detailed finite-element models of the buildings were used. Calculated time histories at piping support points were then used to determine moments throughout critical piping systems. Twenty separate piping models were analyzed. Finally, the responses of piping and safety system components within the buildings were combined with probabilistic failure criteria and event-tree/fault-tree models of the plant safety systems to produce an estimate of the frequency of core melt and radioactive release due to earthquakes

  10. Methodology and application of surrogate plant PRA analysis to the Rancho Seco Power Plant: Final report

    International Nuclear Information System (INIS)

    Gore, B.F.; Huenefeld, J.C.

    1987-07-01

    This report presents the development and the first application of generic probabilistic risk assessment (PRA) information for identifying systems and components important to public risk at nuclear power plants lacking plant-specific PRAs. A methodology is presented for using the results of PRAs for similar (surrogate) plants, along with plant-specific information about the plant of interest and the surrogate plants, to infer important failure modes for systems of the plant of interest. This methodology, and the rationale on which it is based, is presented in the context of its application to the Rancho Seco plant. The Rancho Seco plant has been analyzed using PRA information from two surrogate plants. This analysis has been used to guide development of considerable plant-specific information about Rancho Seco systems and components important to minimizing public risk, which is also presented herein

  11. Nuclear power plants

    International Nuclear Information System (INIS)

    Margulova, T.Ch.

    1976-01-01

    The textbook focuses on the technology and the operating characteristics of nuclear power plants equiped with pressurized water or boiling water reactors, which are in operation all over the world at present. The following topics are dealt with in relation to the complete plant and to economics: distribution and consumption of electric and thermal energy, types and equipment of nuclear power plants, chemical processes and material balance, economical characteristics concerning heat and energy, regenerative preheating of feed water, degassing and condenser systems, water supply, evaporators, district heating systems, steam generating systems and turbines, coolant loops and pipes, plant siting, ventilation and decontamination systems, reactor operation and management, heat transfer including its calculation, design of reactor buildings, and nuclear power plants with gas or sodium cooled reactors. Numerous technical data of modern Soviet nuclear power plants are included. The book is of interest to graduate and post-graduate students in the field of nuclear engineering as well as to nuclear engineers

  12. A Study on Structured Simulation Framework for Design and Evaluation of Human-Machine Interface System -Application for On-line Risk Monitoring for PWR Nuclear Power Plant-

    International Nuclear Information System (INIS)

    Zhan, J.; Yang, M.; Li, S.C.; Peng, M.J.; Yan, S.Y.; Zhang, Z.J.

    2006-01-01

    The operators in the main control room of Nuclear Power Plant (NPP) need to monitor plant condition through operation panels and understand the system problems by their experiences and skills. It is a very hard work because even a single fault will cause a large number of plant parameters abnormal and operators are required to perform trouble-shooting actions in a short time interval. It will bring potential risks if operators misunderstand the system problems or make a commission error to manipulate an irrelevant switch with their current operation. This study aims at developing an on-line risk monitoring technique based on Multilevel Flow Models (MFM) for monitoring and predicting potential risks in current plant condition by calculating plant reliability. The proposed technique can be also used for navigating operators by estimating the influence of their operations on plant condition before they take an action that will be necessary in plant operation, and therefore, can reduce human errors. This paper describes the risk monitoring technique and illustrates its application by a Steam Generator Tube Rupture (SGTR) accident in a 2-loop Pressurized Water Reactor (PWR) Marine Nuclear Power Plant (MNPP). (authors)

  13. Risk management in the electric power sector, v. 16(61)

    International Nuclear Information System (INIS)

    Iliev, Atanas; Minovski, Dragan

    2008-01-01

    This paper presents the basics of the risk theory and the main methods which could be applied for risk management in electrical power system utilities. Taking into consideration that the risk and uncertainty not be completely eliminated, the engineers have to know to manage the risk and uncertainty. The main goal is to minimized the negative effects from accepted risk in order to increase expected incomes and expected profit. Special attention is dedicated to risk management in complex project in Electric Power Systems in a new deregulated electricity market which has the influence to the market stability, expected incomes and quality of the delivered electricity. Specially, the risk management in the companies - producers of the electricity is analysed, since theirs further investments in a rehabilitation of the current power plants as well in the construction of the new plants will be based on the economical principles of profit. (Author)

  14. Risk management in the electric power sector, v. 16(62)

    International Nuclear Information System (INIS)

    Iliev, Atanas; Minovski, Dragan

    2008-01-01

    This paper presents the basics of the risk theory and the main methods which could be applied for risk management in electrical power system utilities. Taking into consideration that the risk and uncertainty not be completely eliminated, the engineers have to know to manage the risk and uncertainty. The main goal is to minimized the negative effects from accepted risk in order to increase expected incomes and expected profit. Special attention is dedicated to risk management in complex project in Electric Power Systems in a new deregulated electricity market which has the influence to the market stability, expected incomes and quality of the delivered electricity. Specially, the risk management in the companies - producers of the electricity is analysed, since theirs further investments in a rehabilitation of the current power plants as well in the construction of the new plants will be based on the economical principles of profit. (Author)

  15. Accident prevention in power plants

    International Nuclear Information System (INIS)

    Steyrer, H.

    Large thermal power plants are insured to a great extent at the Industrial Injuries Insurance Institute of Instrument and Electric Engineering. Approximately 4800 employees are registered. The accident frequency according to an evaluation over 12 months lies around 79.8 per year and 1000 employees in fossil-fired power plants, around 34.1 per year and 1000 employees in nuclear power plants, as in nuclear power plants coal handling and ash removal are excluded. Injuries due to radiation were not registered. The crucial points of accidents are mechanical injuries received on solid, sharp-edged and pointed objects (fossil-fired power plants 28.6%, nuclear power plants 41.5%), stumbling, twisting or slipping (fossil-fired power plants 21.8%, nuclear power plants 19.5%) and injuries due to moving machine parts (only nuclear power plants 12.2%). However, accidents due to burns or scalds obtain with 4.2% and less a lower portion than expected. The accident statistics can explain this fact in a way that the typical power plant accident does not exist. (orig./GL) [de

  16. A genetic algorithm solution for a nuclear power plant risk-cost maintenance model

    International Nuclear Information System (INIS)

    Tong Jiejuan; Mao Dingyuan; Xue Dazhi

    2004-01-01

    Reliability Centered Maintenance (RCM) is one of the popular maintenance optimization methods according to certain kinds of priorities. Traditional RCM usually analyzes and optimizes the maintenance strategy from the viewpoint of component instead of the whole maintenance program impact. Research presented in this paper is a pilot study using PSA techniques in RCM. How to reflect the effect on component unavailability by the maintenance activities such as surveillance testing and preventive maintenance in PSA model is discussed firstly. Based on the discussion, a maintenance risk-cost model is established for global maintenance optimization in a nuclear power plant, and a genetic algorithm (GA) is applied to solve such a model to get the global optimized maintenance strategy. Finally, the result got from a simple test case based on a risk-cost model consisting of 10 components is presented

  17. Relationship between images of risk and anxiety toward radiation. Comparison of radiation from chest X-rays and nuclear power plants

    International Nuclear Information System (INIS)

    Matsui, Yuko

    2003-01-01

    In order to clarify the components of people's images of radiation risk and the determinants for the degree of anxiety about radiation exposure, an investigation was conducted. Two kinds of radiation, from nuclear power plants and during a chest X-ray, which are relatively familiar to people, were focused on. As a result, only a 'dread' factor was common to both radiation types of. Although the degree of anxiety toward both types of radiation showed a positive correlation with the 'dread' image, the anxiety toward X-ray radiation showed a negative correlation with the 'feeling of conquest'. Anxiety toward radiation from nuclear power plants had a negative correlation with 'control by experts'. These results suggest that the words radiation from nuclear power plants' evoke an image of a situation with high radiation exposure, which is beyond the experts' control abilities. (author)

  18. Risk contribution from low power, shutdown, and other operational modes beyond full power

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, D.W.; Brown, T.D. [Sandia National Labs., Albuquerque, NM (United States); Chu, T.L. [Brookhaven National Lab., Upton, NY (United States)] [and others

    1995-04-01

    During 1989 the Nuclear Regulatory Commission (NRC) initiated an extensive program to carefully examine the potential risks during low power and shutdown operations. Two plants, Surry (a pressurized water reactor) and Grand Gulf (a boiling water reactor), were selected for study by Brookhaven National Laboratory and Sandia National Laboratories, respectively. The program objectives included assessing the risks of severe accidents initiated during plant operational states other than full power and comparing estimated core damage frequencies, important accident sequences, and other qualitative and quantitative results with full power accidents as assessed in NUREG-1150. The scope included a Level 3 probabilistic risk assessment (PRA) for traditional internal events and a Level 1 PRA on fire, flooding, and seismically induced core damage sequences. A phased approach was used in Level 1. In Phase 1 the concept of plant operational states (POSs) was developed to provide a better representation of the plant as it transitions from power to nonpower operation. This included a coarse screening analysis of all POSs to identify vulnerable plant configurations, to characterize (on a high, medium, or low basis) potential frequencies of core damage accidents, and to provide a foundation for a detailed Phase 2 analysis. In Phase 2, selected POSs from both Grand Gulf and Surry were chosen for detailed analysis. For Grand Gulf, POS 5 (approximately cold shutdown as defined by Grand Gulf Technical Specifications) during a refueling outage was selected. For Surry, three POSs representing the time the plant spends in midloop operation were chosen for analysis. These included POS 6 and POS 10 of a refueling outage and POS 6 of a drained maintenance outage. Level 1 and Level 2/3 results from both the Surry and Grand Gulf analyses are presented.

  19. Risk contribution from low power, shutdown, and other operational modes beyond full power

    International Nuclear Information System (INIS)

    Whitehead, D.W.; Brown, T.D.; Chu, T.L.; Pratt, W.T.

    1995-01-01

    During 1989 the Nuclear Regulatory Commission (NRC) initiated an extensive program to carefully examine the potential risks during low power and shutdown operations. Two plants, Surry (a pressurized water reactor) and Grand Gulf (a boiling water reactor), were selected for study by Brookhaven National Laboratory and Sandia National Laboratories, respectively. The program objectives included assessing the risks of severe accidents initiated during plant operational states other than full power and comparing estimated core damage frequencies, important accident sequences, and other qualitative and quantitative results with full power accidents as assessed in NUREG-1150. The scope included a Level 3 probabilistic risk assessment (PRA) for traditional internal events and a Level 1 PRA on fire, flooding, and seismically induced core damage sequences. A phased approach was used in Level 1. In Phase 1 the concept of plant operational states (POSs) was developed to provide a better representation of the plant as it transitions from power to nonpower operation. This included a coarse screening analysis of all POSs to identify vulnerable plant configurations, to characterize (on a high, medium, or low basis) potential frequencies of core damage accidents, and to provide a foundation for a detailed Phase 2 analysis. In Phase 2, selected POSs from both Grand Gulf and Surry were chosen for detailed analysis. For Grand Gulf, POS 5 (approximately cold shutdown as defined by Grand Gulf Technical Specifications) during a refueling outage was selected. For Surry, three POSs representing the time the plant spends in midloop operation were chosen for analysis. These included POS 6 and POS 10 of a refueling outage and POS 6 of a drained maintenance outage. Level 1 and Level 2/3 results from both the Surry and Grand Gulf analyses are presented

  20. Maintenance planning for nuclear power plants

    International Nuclear Information System (INIS)

    Mattu, R.K.; Cooper, S.E.; Lauderdale, J.R.

    2004-01-01

    Maintenance planning for nuclear power plants is similar to that in other industrial plants but it is heavily influenced by regulatory rules, with consequent costs of compliance. Steps by the nuclear industry and the Nuclear Regulatory Commission to address that problem include development of guidelines for maintenance of risk-critical equipment, using PRA-based techniques to select a set of equipment that requires maintenance and reliability-centered maintenance (RCM) approaches for determining what maintenance is required. The result of the process is a program designed to ensure effective maintenance of the equipment most critical to plant safety. (author)

  1. A practical approach for implementing risk-based inservice testing of pumps at nuclear power plants

    International Nuclear Information System (INIS)

    Hartley, R.S.; Maret, D.; Seniuk, P.; Smith, L.

    1996-01-01

    The American Society of Mechanical Engineers (ASME) Center for Research and Technology Development's (CRTD) Research Task Force on Risk-Based Inservice Testing has developed guidelines for risk-based inservice testing (IST) of pumps and valves. These guidelines are intended to help the ASME Operation and Maintenance (OM) Committee to enhance plant safety while focussing appropriate testing resources on critical components. This paper describes a practical approach for implementing those guidelines for pumps at nuclear power plants. The approach, as described in this paper, relies on input, direction, and assistance from several entities such as the ASME Code Committees, United States Nuclear Regulatory Commission (NRC), and the National Laboratories, as well as industry groups and personnel with applicable expertise. Key parts of the risk-based IST process that are addressed here include: identification of important failure modes, identification of significant failure causes, assessing the effectiveness of testing and maintenance activities, development of alternative testing and maintenance strategies, and assessing the effectiveness of alternative testing strategies with present ASME Code requirements. Finally, the paper suggests a method of implementing this process into the ASME OM Code for pump testing

  2. A practical approach for implementing risk-based inservice testing of pumps at nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Hartley, R.S. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Maret, D.; Seniuk, P.; Smith, L.

    1996-12-01

    The American Society of Mechanical Engineers (ASME) Center for Research and Technology Development`s (CRTD) Research Task Force on Risk-Based Inservice Testing has developed guidelines for risk-based inservice testing (IST) of pumps and valves. These guidelines are intended to help the ASME Operation and Maintenance (OM) Committee to enhance plant safety while focussing appropriate testing resources on critical components. This paper describes a practical approach for implementing those guidelines for pumps at nuclear power plants. The approach, as described in this paper, relies on input, direction, and assistance from several entities such as the ASME Code Committees, United States Nuclear Regulatory Commission (NRC), and the National Laboratories, as well as industry groups and personnel with applicable expertise. Key parts of the risk-based IST process that are addressed here include: identification of important failure modes, identification of significant failure causes, assessing the effectiveness of testing and maintenance activities, development of alternative testing and maintenance strategies, and assessing the effectiveness of alternative testing strategies with present ASME Code requirements. Finally, the paper suggests a method of implementing this process into the ASME OM Code for pump testing.

  3. Socio-environmental impacts of Angra dos Reis nuclear power plant

    International Nuclear Information System (INIS)

    Rosa, L.P.; Hesles, J.B.S.

    1984-01-01

    Technological aspects and the social problematic inherent to implementation of nuclear power plants in Brazil are studied. it is showed the study in two levels: one of them, attacks aspects linked to nuclear energy and their risks in Brazil; the other one, treats of impacts of the Angra dos Reis nuclear power plants on the local comunity. (M.C.K.) [pt

  4. Integrated societal risk assessment framework for nuclear power and renewable energy sources

    International Nuclear Information System (INIS)

    Lee, Sang Hun; Kang, Hyun Gook

    2015-01-01

    Recently, the estimation of the social cost of energy sources has been emphasized as various novel energy options become feasible in addition to conventional ones. In particular, the social cost of introducing measures to protect power-distribution systems from power-source instability and the cost of accident-risk response for various power sources must be investigated. To account for these risk factors, an integrated societal risk assessment framework, based on power-uncertainty analysis and accident-consequence analysis, is proposed. In this study, we applied the proposed framework to nuclear power plants, solar photovoltaic systems, and wind-turbine generators. The required capacity of gas-turbine power plants to be used as backup power facilities to compensate for fluctuations in the power output from the main power source was estimated based on the performance indicators of each power source. The average individual health risk per terawatt-hours (TWh) of electricity produced by each power source was quantitatively estimated by assessing accident frequency and the consequences of specific accident scenarios based on the probabilistic risk assessment methodology. This study is expected to provide insight into integrated societal risk analysis, and can be used to estimate the social cost of various power sources

  5. Integrated societal risk assessment framework for nuclear power and renewable energy sources

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Hun; Kang, Hyun Gook [Dept. of Nuclear and Quantum Engineering, KAIST, Daejeon (Korea, Republic of)

    2015-06-15

    Recently, the estimation of the social cost of energy sources has been emphasized as various novel energy options become feasible in addition to conventional ones. In particular, the social cost of introducing measures to protect power-distribution systems from power-source instability and the cost of accident-risk response for various power sources must be investigated. To account for these risk factors, an integrated societal risk assessment framework, based on power-uncertainty analysis and accident-consequence analysis, is proposed. In this study, we applied the proposed framework to nuclear power plants, solar photovoltaic systems, and wind-turbine generators. The required capacity of gas-turbine power plants to be used as backup power facilities to compensate for fluctuations in the power output from the main power source was estimated based on the performance indicators of each power source. The average individual health risk per terawatt-hours (TWh) of electricity produced by each power source was quantitatively estimated by assessing accident frequency and the consequences of specific accident scenarios based on the probabilistic risk assessment methodology. This study is expected to provide insight into integrated societal risk analysis, and can be used to estimate the social cost of various power sources.

  6. Application of the accident consequences model of the German risk study to assessments of accident risks in different types of nuclear power plants

    International Nuclear Information System (INIS)

    Ehrhardt, J.; Bayer, A.

    1982-01-01

    Within the scope of the 'German Risk Study for Nuclear Power Plants' (Phase A) the accident consequence model UFOMOD was developed in the Karlsruhe Nuclear Research Center. This model originally developed for pressurized water reactors has now been extended in order to obtain results about accidental releases of activity from fast breeder and high-temperature reactors, too. (RW) [de

  7. The retirement cliff: Power plant lives and their policy implications

    International Nuclear Information System (INIS)

    Rode, David C.; Fischbeck, Paul S.; Páez, Antonio R.

    2017-01-01

    This paper examines more than a century of U.S. power plant additions and retirements in conjunction with several decades of utility capital investment data. While policy analyses often invoke assumptions of power plant book life, relatively little analysis has focused on the physical life of power-generating assets. The average age of the U.S. generator fleet has increased significantly over time despite continued investment, in part because more recent investment has tended to focus on shorter-lived assets. This may be due in part to risk-averse power sector investors and lenders responding rationally to regulatory uncertainty in a deregulated market environment. Power plant retirement trends suggest that the pace of retirements will increase significantly in the decade after 2030 for most reasonable estimates of physical life. These capital investment trends have important consequences for carbon policy and highlight the importance of including consideration of the longer term—particularly when evaluating more significant decarbonization policies. - Highlights: • Many policy analyses neglect the physical lives of power plants. • A large database of U.S. power plant additions and retirements is examined. • The average age of power plants has steadily increased despite growing investment. • Long-term CO 2 reduction strategies are challenged by increases in plant retirements.

  8. Financing Nuclear Power Plant Projects. A New Paradigm?

    International Nuclear Information System (INIS)

    Pehuet Lucet, Fabienne

    2015-05-01

    There are currently 435 operable nuclear power reactors around the world, with a further 71 under construction. Two main proven financing models were applied to nuclear plants in the past: the national model, and the corporate model. The historical model of financing is the national model. It allowed for the most efficient risk allocation model in then-regulated national electricity markets: government or state-owned utilities with government guarantee assumed the risks of building nuclear power plants locally. The national model has proven to be efficient in France, Russia and the USA where it was modified to support private business initiatives. It was then replicated in Japan, Korea and China where significant nuclear programs were developed. In the corporate business model, the owner of the plant assumes most of the risk, but various schemes are used to mitigate the owner's risk by transmitting large areas of risks to others: vendors for construction risk as in Finland, government through loans guarantees etc. As projects became international, a set of common principles were approved by OECD countries concerning financing and the role of Export Credit Agencies. The objective was to provide competition rules whereby exporters compete on the basis of the price and quality of their products rather than the financial terms provided. Various combinations of these models were and still are implemented. Pure Project Finance was not implemented for nuclear power plants, but the model nurtures reflections about new financing models. The context in which nuclear power projects are now decided and financed changed drastically: it is a new paradigm. Risk allocation and financial conditions are at the forefront of competition to win new nuclear projects' tenders insofar as reducing uncertainties is a decisive competition edge. In a context of electricity market deregulation and high construction risks, investors and lenders require more and more securities to

  9. Survey of numerical safety targets for nuclear power plants

    International Nuclear Information System (INIS)

    Kelley, A.P. Jr.; Buttemer, D.R.

    1981-04-01

    The construction of a nuclear power plant implies, as does the construction of any major public work, the acceptance of a finite degree of risk. This risk can be reduced by an increased investment in engineered safeguards. However, at some level of risk, overinvestment in safety can render the project uneconomical. Because of the desirability of fixing safety standards on an absolute basis, there has long been an interest in establishing numerical risk criteria for the design, construction, and operation of nuclear power plants. Interest in the subject of numerical safety goals has recently been intensified by the Three Mile Island Action Plan. The USNRC has been directed by Congress to develop a national safety goal for reactor regulation. This report summarizes actions which have been historically, and are currently, taking place toward establishing national numerical risk targets for reactor regulation. Emphasis is placed upon actions taken, or currently being taken, by federal regulatory agencies and directly associated advisory bodies

  10. Track 6: safety and risk management. Plant operational risk management. Plant Configuration Risk Assessment Methodology Development for Periodic Maintenance

    International Nuclear Information System (INIS)

    Yang, Huichang; Chung, Chang Hyun; Sung, Key Yong

    2001-01-01

    As the operation experiences of nuclear power plants (NPPs) in Korea accumulate and NPP safety functions become enhanced, the role of stable and optimal NPP operation within acceptable safety criteria becomes important at present. To accomplish the goal of safe and optimal operation, maintenance and its related activities should be regarded as the issues of most concern. Studies of methodologies for maintenance improvement and optimization have focused on system performance rather than on the hardware itself. From this point of view, the probabilistic methods are most useful. In terms of risk including core damage frequency and unavailability, the cause that might impact plant safety during normal maintenance activities can be identified and evaluated effectively. The results from these probabilistic analyses can provide insightful information for the reallocation of risk-contributing maintenance activity. This information can be utilized in a way that separates the significant risk-contributing maintenance activities from each other unless they are timely related. In Korea, the risk-monitoring program for operating NPPs is under development and will be implemented in 2003. To accomplish the risk-monitoring program objectives, suitable risk evaluation methods should be developed before the implementation of the risk-monitoring program. The plant configuration assessment methodology was developed for these reasons, and this method is to incorporate the field experiences into the risk calculation exactly within the limit of probabilistic methods. During normal plant operation, the plant operational risk changes frequently depending on the status of the plant system and the arrangement of the components. Specific plant systems or components are typically removed from service because of random equipment failure, planned preventive/predictive maintenance, corrective maintenance, surveillance testing, and operational bypass activities, and such events usually impact the

  11. Multiple external hazards compound level 3 PSA methods research of nuclear power plant

    Science.gov (United States)

    Wang, Handing; Liang, Xiaoyu; Zhang, Xiaoming; Yang, Jianfeng; Liu, Weidong; Lei, Dina

    2017-01-01

    2011 Fukushima nuclear power plant severe accident was caused by both earthquake and tsunami, which results in large amount of radioactive nuclides release. That accident has caused the radioactive contamination on the surrounding environment. Although this accident probability is extremely small, once such an accident happens that is likely to release a lot of radioactive materials into the environment, and cause radiation contamination. Therefore, studying accidents consequences is important and essential to improve nuclear power plant design and management. Level 3 PSA methods of nuclear power plant can be used to analyze radiological consequences, and quantify risk to the public health effects around nuclear power plants. Based on multiple external hazards compound level 3 PSA methods studies of nuclear power plant, and the description of the multiple external hazards compound level 3 PSA technology roadmap and important technical elements, as well as taking a coastal nuclear power plant as the reference site, we analyzed the impact of off-site consequences of nuclear power plant severe accidents caused by multiple external hazards. At last we discussed the impact of off-site consequences probabilistic risk studies and its applications under multiple external hazards compound conditions, and explained feasibility and reasonableness of emergency plans implementation.

  12. Risk Importance Measures in the Designand Operation of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Vrbanic I.; Samanta P.; Basic, I

    2017-10-31

    This monograph presents and discusses risk importance measures as quantified by the probabilistic risk assessment (PRA) models of nuclear power plants (NPPs) developed according to the current standards and practices. Usually, PRA tools calculate risk importance measures related to a single ?basic event? representing particular failure mode. This is, then, reflected in many current PRA applications. The monograph focuses on the concept of ?component-level? importance measures that take into account different failure modes of the component including common-cause failures (CCFs). In opening sections the roleof risk assessment in safety analysis of an NPP is introduced and discussion given of ?traditional?, mainly deterministic, design principles which have been established to assign a level of importance to a particular system, structure or component. This is followed by an overview of main risk importance measures for risk increase and risk decrease from current PRAs. Basic relations which exist among the measures are shown. Some of the current practical applications of risk importancemeasures from the field of NPP design, operation and regulation are discussed. The core of the monograph provides a discussion on theoreticalbackground and practical aspects of main risk importance measures at the level of ?component? as modeled in a PRA, starting from the simplest case, single basic event, and going toward more complexcases with multiple basic events and involvements in CCF groups. The intent is to express the component-level importance measures via theimportance measures and probabilities of the underlying single basic events, which are the inputs readily available from a PRA model andits results. Formulas are derived and discussed for some typical cases. The formulas and their results are demonstrated through some practicalexamples, done by means of a simplified PRA model developed in and run by RiskSpectrum? tool, which are presented in the appendices. The

  13. The evaluation of environmental effects of nuclear power plants

    International Nuclear Information System (INIS)

    Oezyurt, M.; Iyit, L.; Seyitogullari, S.

    2006-01-01

    Energy is today one of the most significant topics in the world. Humans are investigating alternative energy resources due to the fossil energy sources to be exhausted in future. As known, the life of energy resources such as coal and oil is limited. Natural gas will cover the need just for a limited period. On the other hand, developing population will increase the need of energy for the next generation. Therefore, alternative energy has gained much significance in recent years. Nuclear energy is the most criticized energy in public opinion. About 17 pct. of the electric need in the world is being covered by nuclear power plants . This ratio is over 30 pct. in European Union and over 78.2 pct. in France. The most significant risk as regard with environmental pollution is radioactive wastes for these plants. The opposite sides towards nuclear energy claim about the accidents of nuclear power plants and deaths in short and long terms. As long as the security rules are applied, nuclear power plants affect neither human nor environmental health in a detrimental way. The radiation emission scattered by nuclear power plants is very low. In this work, first of all nuclear energy was evaluated from a standpoint of environmental pollution and both positive and negative effects were investigated. As a result, the humanity will have to benefit from all the alternative energy resources , the nuclear energy as well, in order not to live in a dark world. Every technology has its own risks. It seems that if nuclear energy power plants are operated in high technology conditions it will be un given up for humanity

  14. Preliminary regulatory assessment of nuclear power plants vulnerabilities

    International Nuclear Information System (INIS)

    Kostadinov, V.; Petelin, S.

    2004-01-01

    Preliminary attempts to develop models for nuclear regulatory vulnerability assessment of nuclear power plants are presented. Development of the philosophy and computer tools could be new and important insight for management of nuclear operators and nuclear regulatory bodies who face difficult questions about how to assess the vulnerability of nuclear power plants and other nuclear facilities to external and internal threats. In the situation where different and hidden threat sources are dispersed throughout the world, the assessment of security and safe operation of nuclear power plants is very important. Capability to evaluate plant vulnerability to different kinds of threats, like human and natural occurrences and terrorist attacks and preparation of emergency response plans and estimation of costs are of vital importance for assurance of national security. On the basis of such vital insights, nuclear operators and nuclear regulatory bodies could plan and optimise changes in oversight procedures, organisations, equipment, hardware and software to reduce risks taking into account security and safety of nuclear power plants operation, budget, manpower, and other limitations. Initial qualitative estimations of adapted assessments for nuclear applications are shortly presented. (author)

  15. Probabilistic risk assessment in the nuclear power industry

    International Nuclear Information System (INIS)

    Fullwood, R.R.; Hall, R.E.

    1988-01-01

    This book describes the more important improvements in risk assessment methodology developed over the last decade. The book covers the following areas - a general view of risk pertaining to nuclear power, mathematics necessary to understand the text, a concise overview of the light water reactors and their features for protecting the public, probabilities and consequences calculated to form risk assessment to the plant, and 34 applications of probabilistic risk assessment (PRA) in the power generation industry. There is a glossary of acronyms and unusual words and a list of references. (author)

  16. Risk evaluation for motor operated valves in an Inservice Testing Program at a PWR nuclear power plant in Taiwan

    International Nuclear Information System (INIS)

    Li, Y.C.; Chen, K.T.; Su, Y.L.; Ting, K.; Chien, F.T.; Li, G.D.; Huang, S.H.

    2012-01-01

    Safety related valves such as Motor Operated Valves (MOV), Air Operated Valves (AOV) or Check Valves (CV) play an important role in nuclear power plant. Functioning of these valves mainly aim at emergency reactivity control, post-accident residue heat removal, post-accident radioactivity removal and containment isolation when a design basis accident occurred. In order to maintain these valves under operable conditions, an Inservice Testing Program (IST) is defined for routine testing tasks based on the ASME Boiler and Pressure Vessel Code section XI code requirements. Risk based Inservice Testing Programs have been studied and developed extensively in the nuclear energy industry since the 1990s. Risk Based evaluations of IST can bring positive advantages to the licensee such as identifying the vulnerability of the system, reducing unnecessary testing burden, concentrating testing resources on the critical pass oriented valves and saving plant’s personnel dose exposure. This risk evaluation is incorporated with quantitative and qualitative analyses to the Motor Operated Valves under current Inservice Testing Program for PWR nuclear power plant in Taiwan. With the outcome of the risk classifications for the safety related MOVs through numerical or deterministic analyses, a risk based testing frequency relief is suggested to demonstrate the benefits received from the risk based Inservice Testing Program. The goal made of this study, it could be as a reference and cornerstone for the licensee to perform overall scope Risk-Informed Inservice Testing Program (RI-IST) evaluation by referring relevant methodologies established in this study.

  17. Off-shore nuclear power plant

    International Nuclear Information System (INIS)

    Nakanishi, T.

    1980-01-01

    In order to avoid losses of energy and seawater pollution an off-shore nuclear power plant is coupled with a power plant which utilizes the temperature difference between seawater and hot reactor cooling water. According to the invention the power plant has a working media loop which is separated from the nuclear power plant. The apparative equipment and the operational characteristics of the power plant are the subject of the patent. (UWI) [de

  18. Solar thermal power plants

    International Nuclear Information System (INIS)

    Schnatbaum, L.

    2009-01-01

    The solar thermal power plant technology, the opportunities it presents and the developments in the market are outlined. The focus is on the technology of parabolic trough power plants, a proven technology for solar power generation on a large scale. In a parabolic trough power plant, trough-shaped mirrors concentrate the solar irradiation onto a pipe in the focal line of the collector. The thermal energy thus generated is used for electricity generation in a steam turbine. Parabolic trough plants can be combined with thermal storage and fossil or biomass fired heat exchangers to generate electricity even when the sun is not shining. Solar Millennium AG in Erlangen has developed the first power plant of this kind in Europe. After two years of construction the plant started operation in Southern Spain in 2008. This one and its sister projects are important steps leading the way for the whole market. The paper also covers the technological challenges, the key components used and the research and development activities concerning this technology. Solar thermal power plants are ideal for covering peak and medium loads in power grids. In hybrid operation they can also cover base-load. The Solar Chimney power plant, another striking technology for the conversion of solar into electric energy, is described briefly. The paper concludes with a look at the future - the import of solar energy from the deserts of North Africa to central Europe. (author)

  19. Energy choices and risk beliefs: is it just global warming and fear of a nuclear power plant accident?

    Science.gov (United States)

    Greenberg, Michael; Truelove, Heather Barnes

    2011-05-01

    A survey of 3,200 U.S. residents focused on two issues associated with the use of nuclear and coal fuels to produce electrical energy. The first was the association between risk beliefs and preferences for coal and nuclear energy. As expected, concern about nuclear power plant accidents led to decreased support for nuclear power, and those who believed that coal causes global warming preferred less coal use. Yet other risk beliefs about the coal and nuclear energy fuel cycles were stronger or equal correlates of public preferences. The second issue is the existence of what we call acknowledged risk takers, respondents who favored increased reliance on nuclear energy, although also noting that there could be a serious nuclear plant accident, and those who favored greater coal use, despite acknowledging a link to global warming. The pro-nuclear group disproportionately was affluent educated white males, and the pro-coal group was relatively poor less educated African-American and Latino females. Yet both shared four similarities: older age, trust in management, belief that the energy facilities help the local economy, and individualistic personal values. These findings show that there is no single public with regard to energy preferences and risk beliefs. Rather, there are multiple populations with different viewpoints that surely would benefit by hearing a clear and comprehensive national energy life cycle policy from the national government. © 2010 Society for Risk Analysis.

  20. Power plant cycle chemistry - a currently neglected power plant chemistry discipline

    International Nuclear Information System (INIS)

    Bursik, A.

    2005-01-01

    Power plant cycle chemistry seems to be a stepchild at both utilities and universities and research organizations. It is felt that other power plant chemistry disciplines are more important. The last International Power Cycle Chemistry Conference in Prague may be cited as an example. A critical review of the papers presented at this conference seems to confirm the above-mentioned statements. This situation is very unsatisfactory and has led to an increasing number of component failures and instances of damage to major cycle components. Optimization of cycle chemistry in fossil power plants undoubtedly results in clear benefits and savings with respect to operating costs. It should be kept in mind that many seemingly important chemistry-related issues lose their importance during forced outages of units practicing faulty plant cycle chemistry. (orig.)

  1. Operation of Finnish nuclear power plants

    International Nuclear Information System (INIS)

    Tossavainen, K.

    1990-08-01

    During the first quarter of 1990 the Finnish nuclear power plant units Loviisa 1 and 2 and TVO I and II were in commercial operation for most of the time. Nuclear electricity accounted for 32.5% of the total Finnish electricity production during this quarter. The load factor average of the nuclear power plant units was 99.0%. An international nuclear event scale has been introduced for the classification of nuclear power plant events according to their nuclear and radiation safety significance. The scale first undergoes about a year long trial period in several countries. on the scale, events are divided into levels from 1 to 7 of which events at Level 7 are the most serious. Furthermore, Level 0 (Below Scale) is used for events with no safety significance. All events which occurred at the Finnish nuclear power plants this quarter are classified as Level 0. Occupational radiation doses and external releases of radioactivity were considerably below authorised limits. At the Loviisa plant, a back-up emergency feedwater system independent of the plant's other systems has been introduced which offers a new, alternative means of removing residual heat from the reactor. Owing to this system, the risk of a severe accident has been further reduced. At the TVO plants, systems have been introduced by which accident sequences which lead to containment failure could be eliminated and the consequences of a potential severe accident could be mitigated. In this report, also the release of short-lived radioactive materials along the transfer route of an irradiated sample is described which occured at the FiR 1 research reactor. The amounts of radioactive materials individuals received in their bodies in connection with this event were very low

  2. Control of power plants and power systems. Proceedings

    International Nuclear Information System (INIS)

    Canales-Ruiz, R.

    1996-01-01

    The 88 papers in this volume constitute the proceedings of the International Federation of Automatic Control Symposium held in Mexico in 1995. The broad areas which they cover are: self tuning control; power plant operations; dynamic stability; fuzzy logic applications; power plants modelling; artificial intelligence applications; power plants simulation; voltage control; control of hydro electric units; state estimation; fault diagnosis and monitoring systems; system expansion and operation planning; security assessment; economic dispatch and optimal load flow; adaptive control; distribution; transient stability and preventive control; modelling and control of nuclear plant; knowledge data bases for automatic learning methods applied to power system dynamic security assessment; control of combined cycle units; power control centres. Separate abstracts have been prepared for the three papers relating to nuclear power plants. (UK)

  3. How to provide risk information. Based on citizen's evaluation of messages concerning radiation protection and anti-earthquake measures of nuclear power plant

    International Nuclear Information System (INIS)

    Tsuchiya, Tomoko; Kosugi, Motoko; Nakamura, Yasushi; Takahashi, Shigeaki; Harayama, Satoko

    2009-01-01

    The Framework for Nuclear Energy Policy in Japan, decided in 2005, requests implementation of risk communication to regain social trust on nuclear industry. Electric power companies, however, have few experiences of providing risk information as the first step of risk communication. This report analyzes which message is understandable, useful and trustworthy, by comparing two sets of different messages concerning radiation protection and anti-earthquake measures of nuclear power plant, respectively, based on interview survey for 30 people live in Tokyo metropolitan area. Participants in our survey evaluate the message about radiation protection including risk information is more reliable than one without risk information, but the former is less understandable and more anxious than the latter. In the case of messages regarding seismic measures of nuclear power plant, people are not satisfied with the argument which anti-earthquake measures are implemented, but want to know adequate grounds on which to admit that those measures are thorough. Another message of seismic measures we drafted contains basic knowledge about scales of earthquake, and shows that nuclear industry will consider bigger earthquake than ones in the past records, learn from past experience and improve their measures. 70% of participants assess this message more understandable, useful and trustworthy than the other to explain only seismic measures implemented. (author)

  4. Nuclear energy research initiative, an overview of the cooperative program for the risk-informed assessment of regulatory and design requirements for future nuclear power plants

    International Nuclear Information System (INIS)

    Ritterbusch, Stanley E.

    2000-01-01

    EPRI sstudies have shown that nuclear plant capital costs will have to decrease by about 35% to 40% to be competitive with fossil-generated electricity in the Unite States. Also, the ''first concrete'' to fuel load construction schedule will have to be decreased to less than 40 months. Therefore, the U. S. Department of Energy (DOE) initiate the Nuclear Energy Research Initiative (NERI) and ABB CENP proposed a cooperative program with Sandia National Laboratory (SNL) and Duke Engineering and Services (DE and S) to begin an innovative research effort to drastically cut the cost of new nuclear power plant construction for the U. S. de-regulated market place. This program was approved by the DOE through three separate but coordinated ''cooperative agreements.'' They are the ''Risk-Informed Assessment of Regulatory and Design Requirements for Future Nuclear Power Plants'' (Risk-Informed NPP), the ''Smart Nuclear Power Plant Program'' (Smart-NPP), and ''Design, Procure, Construct, Install and Test'' (DPCIT) Program. DOE funded the three cooperative agreements at a level of $2.6 million for the first year of the program. Funding for the complete program is durrently at a level $6.9 million, however, ABB CENP and all partners anticipate that the scope of the NERI program will be increased as a result of the overall importance of NERI to the U. S. Government. The Risk-Informed NPP program, which is aimed at revising costly regularory and design requirements without reducing overall plant safety, has two basic tasks: ''development of Risk-Informed Methods'' and ''strengthening the Reliability Database.'' The overall objective of the first task is to develop a scientific, risk-informed approach for identifying and simplifying deterministic industry standards, regulatory requirements, and safety systems that do not significantly contribute to nuclear power plant reliability and safety. The second basic task is to develop a means for strengthening the reliability database

  5. Assessment of direct radiological risk and indirect associated toxic risks originated by Coal-Fired Power Plants

    OpenAIRE

    Dinis, M. L.; Fiúza, António; Góis, Joaquim; Carvalho, José Soeiro de; Meira Castro, A C

    2011-01-01

    Over the past few decades there has been some discussion concerning the increase of the natural background radiation originated by coal-fired power plants, due to the uranium and thorium content present in combustion ashes. The radioactive decay products of uranium and thorium, such as radium, radon, polonium, bismuth and lead, are also released in addition to a significant amount of 40K. Since the measurement of radioactive elements released by the gaseous emissions of coal power plants i...

  6. Safety-related decision making at a nuclear power plant

    International Nuclear Information System (INIS)

    Vaurio, J.K.

    1998-01-01

    The decision making environment of an operating nuclear power plant is presented. The organizations involved, their roles and interactions as well as the main influencing factors and decision criteria are described. The focus is on safety-related decisions, and the framework is based on the situation at Loviisa power station. The role of probabilistic safety assessment (PSA) is illustrated with decisions concerning plant modifications, optimization, acceptance of temporary configurations and extended repair times. Suggestions are made for rational and flexible risk-based control of allowed times to operate the plant with some components out of service. (orig.)

  7. Preliminary risk assessment of Power Plant Plomin site contaminated by radioactive slag and ash

    International Nuclear Information System (INIS)

    Skanata, D.; Sinka, D.; Lokner, V.; Schaller, A.

    1996-01-01

    There is a certain number of radioactively contaminated sites in the Republic of Croatia, one of them being known as Power Plant Plomin site, which contains radioactive slag and ash. Due to a relatively high quantity of the deposited material, as well as relatively high population density of the neighbouring area, it is very important to assess the impact of the site on human health and environment. Using RESRAD computer code and PATHRAE method a preliminary assessment of doses and radiation risks for the workers who spend most of their working day at the pile has been performed. PATHRAE method has also been used for the assessment of radiation risks for the neighbouring population. The assessment is preliminary in its character due to the lack of input data. On the basis of assessment results, recommendations are being given comprising measurements to be taken with a view to coming up with the final risk assessment, as well as protective measures which should be undertaken in the meantime. (author)

  8. Failures of knowledge production in nuclear power risk management

    International Nuclear Information System (INIS)

    Sanne, Johan M.

    2008-09-01

    Risks are ascribed in processes of knowledge production, where risk objects are defined and measures taken. This knowledge is also the basis for regulatory action. Thus, uncertainties in knowledge production, based upon choices of assumptions, methods, calculations and evidence criteria for reliable data create vulnerabilities for risk management and risk regulation. A recent incident in Swedish nuclear power plant provides an opportunity to develop theories of knowledge production in complex organizations. Knowledge modes within nuclear power can be characterized as either calculated logics where evidence claims need numbers, real time logics based upon subtle signals and tacit knowledge or as policy logics, navigating between internal and external demands for safety, trustworthiness and profit. The plant had neither foreseen the triggering event nor designed the plant to withstand it. I analyze how the plant and the regulator have interpreted the event, its significance and the measures taken to prevent similar events. I also discuss alternative interpretations, lack of knowledge and the generic deficiencies in knowledge production that the event indicates. First, the plant was not as robustly designed as expected. Deficiencies in diversification may have been caused by overconfidence in the reliability of its design. Second, inadequate design was ascribed to various deficient knowledge production processes: original design of the plant, reconstruction or caused by inadequate learning from previous events. The failures in knowledge production were probably caused by insufficient integration of different knowledge processes and limitations in engineering analysis. Knowledge about risks from nuclear power operations is mainly based upon calculations and simulations, not upon real events. But knowledge and design could be improved also without accidents. Control room operators and maintenance staff can provide invaluable knowledge and methods; to improve causal

  9. Failures of knowledge production in nuclear power risk management

    Energy Technology Data Exchange (ETDEWEB)

    Sanne, Johan M.

    2008-09-15

    Risks are ascribed in processes of knowledge production, where risk objects are defined and measures taken. This knowledge is also the basis for regulatory action. Thus, uncertainties in knowledge production, based upon choices of assumptions, methods, calculations and evidence criteria for reliable data create vulnerabilities for risk management and risk regulation. A recent incident in Swedish nuclear power plant provides an opportunity to develop theories of knowledge production in complex organizations. Knowledge modes within nuclear power can be characterized as either calculated logics where evidence claims need numbers, real time logics based upon subtle signals and tacit knowledge or as policy logics, navigating between internal and external demands for safety, trustworthiness and profit. The plant had neither foreseen the triggering event nor designed the plant to withstand it. I analyze how the plant and the regulator have interpreted the event, its significance and the measures taken to prevent similar events. I also discuss alternative interpretations, lack of knowledge and the generic deficiencies in knowledge production that the event indicates. First, the plant was not as robustly designed as expected. Deficiencies in diversification may have been caused by overconfidence in the reliability of its design. Second, inadequate design was ascribed to various deficient knowledge production processes: original design of the plant, reconstruction or caused by inadequate learning from previous events. The failures in knowledge production were probably caused by insufficient integration of different knowledge processes and limitations in engineering analysis. Knowledge about risks from nuclear power operations is mainly based upon calculations and simulations, not upon real events. But knowledge and design could be improved also without accidents. Control room operators and maintenance staff can provide invaluable knowledge and methods; to improve causal

  10. Modifications to nuclear power plants. Safety guide

    International Nuclear Information System (INIS)

    2004-01-01

    This Safety Guide was prepared under the IAEA's programme for safety standards for nuclear power plants. It supplements Section 7 of the Safety Requirements publication on Safety of Nuclear Power Plants: Operation, which establishes the safety requirements for the modification of nuclear power plants. Reasons for carrying out modifications to nuclear power plants may include: (1) maintaining or strengthening existing safety provisions and thus maintaining consistency with or improving on the current design. (2) recovering from plant faults. (3) improving the thermal performance or increasing the power rating of the plant. (4) increasing the maintainability of the plant, reducing the radiation exposure of personnel or reducing the costs of plant maintenance. And (5) extending the design life of the plant. Most modifications, made on the basis of operating experience, are intended to improve on the design or to improve operational performance and flexibility. Some are rendered necessary by new regulatory requirements, ageing of the plant or obsolescence of equipment. However, the benefits of regularly updating the plant design can be jeopardized if modifications are not kept under rigorous control throughout the lifetime of the plant. The need to reduce costs and improve efficiency, in combination with changes to the structure of the electricity generation sector of the economy in many countries, has led many companies to make changes in the structure of the operating organization for nuclear power plants. Whatever the reason for such organizational changes, consideration should be given to the effects of those changes with the aim of ensuring that they would have no impacts that would compromise the safety of the plant. The objective of this Safety Guide is to provide guidance and recommendations on controlling activities relating to modifications at nuclear power plants in order to reduce risk and to ensure that the configuration of the plant is at all times under

  11. Modifications to nuclear power plants. Safety guide

    International Nuclear Information System (INIS)

    2007-01-01

    This Safety Guide was prepared under the IAEA's programme for safety standards for nuclear power plants. It supplements Section 7 of the Safety Requirements publication on Safety of Nuclear Power Plants: Operation, which establishes the safety requirements for the modification of nuclear power plants. Reasons for carrying out modifications to nuclear power plants may include: (1) maintaining or strengthening existing safety provisions and thus maintaining consistency with or improving on the current design. (2) recovering from plant faults. (3) improving the thermal performance or increasing the power rating of the plant. (4) increasing the maintainability of the plant, reducing the radiation exposure of personnel or reducing the costs of plant maintenance. And (5) extending the design life of the plant. Most modifications, made on the basis of operating experience, are intended to improve on the design or to improve operational performance and flexibility. Some are rendered necessary by new regulatory requirements, ageing of the plant or obsolescence of equipment. However, the benefits of regularly updating the plant design can be jeopardized if modifications are not kept under rigorous control throughout the lifetime of the plant. The need to reduce costs and improve efficiency, in combination with changes to the structure of the electricity generation sector of the economy in many countries, has led many companies to make changes in the structure of the operating organization for nuclear power plants. Whatever the reason for such organizational changes, consideration should be given to the effects of those changes with the aim of ensuring that they would have no impacts that would compromise the safety of the plant. The objective of this Safety Guide is to provide guidance and recommendations on controlling activities relating to modifications at nuclear power plants in order to reduce risk and to ensure that the configuration of the plant is at all times under

  12. Planning for risk-informed/performance-based fire protection at nuclear power plants. Final report

    International Nuclear Information System (INIS)

    Najafi, B.; Parkinson, W.J.; Lee, J.A.

    1997-12-01

    This document presents a framework for discussing issues and building consensus towards use of fire modeling and risk technology in nuclear power plant fire protection program implementation. The plan describes a three-phase approach: development of core technologies, implementation of methods, and finally, case studies and pilot applications to verify viability of such methods. The core technologies are defined as fire modeling, fire and system tests, use of operational data, and system and risk techniques. The implementation phase addresses the programmatic issues involved in implementing a risk-informed/performance-based approach in an integrated approach with risk/performance measures. The programmatic elements include: (1) a relationship with fire codes and standards development as defined by the ongoing effort of NFPA for development of performance-based standards; (2) the ability for NRC to undertake inspection and enforcement; and (3) the benefit to utilities in terms of cost versus safety. The case studies are intended to demonstrate applicability of single issue resolution while pilot applications are intended to check the applicability of the integrated program as a whole

  13. Mortality risk in a historical cohort of nuclear power plant workers in Germany: results from a second follow-up

    Energy Technology Data Exchange (ETDEWEB)

    Merzenich, Hiltrud; Troeltzsch, Katrin; Ruecker, Kai; Buncke, Johanna; Blettner, Maria [University Medical Center Mainz, Institute of Medical Biostatistics, Epidemiology and Informatics, Mainz (Germany); Hammer, Gael P. [University Medical Center Mainz, Institute of Medical Biostatistics, Epidemiology and Informatics, Mainz (Germany); Laboratoire National de Sante E.P., Registre Morphologique des Tumeurs, Dudelange (Luxembourg); Fehringer, Franz [Berufsgenossenschaft Energie Textil Elektro Medienerzeugnisse (BGETEM), Cologne (Germany)

    2014-05-15

    Possible health effects of low and protracted doses of ionizing radiation are relevant for persons who are exposed to an occupational context like nuclear industry workers. A historical cohort study was therefore conducted to examine mortality risks following occupational radiation exposure among 4,844 German nuclear power plant workers. This cohort included workers from ten nuclear power plants with an observational period from 1991 until 1997. The results of an enlarged cohort with 8,972 workers from all 17 nuclear power plants in West Germany are now available. During the extended follow-up period from 1991 to 2008, a total of 310 deaths among men were observed. The standardized mortality ratio (SMR) from all causes of deaths was estimated at 0.50 [95 % confidence interval (CI) 0.45-0.56]. A total of 126 deaths due to cancer occurred (SMR = 0.65; 95 % CI 0.51-0.82) and seven deaths due to leukemia (SMR = 1.23; 95 % CI 0.42-2.84). Overall, a reduced mortality compared to the general population of West Germany was observed indicating a healthy worker effect. In the dose-response analysis, no statistically significant risk due to ionizing radiation was seen. The hazard ratio (HR/mSv) for leukemia excluding chronic lymphocytic leukemia was estimated at 1.004 (95 % CI 0.997-1.011). In conclusion, the cohort is small and made up of young workers, most of whom were still employed at the end of the observational period in 2008. Results of the external analysis are difficult to interpret as influenced by a healthy worker effect. In the internal analysis, no excess of risk due to radiation was detected. (orig.)

  14. Mortality risk in a historical cohort of nuclear power plant workers in Germany: results from a second follow-up

    International Nuclear Information System (INIS)

    Merzenich, Hiltrud; Troeltzsch, Katrin; Ruecker, Kai; Buncke, Johanna; Blettner, Maria; Hammer, Gael P.; Fehringer, Franz

    2014-01-01

    Possible health effects of low and protracted doses of ionizing radiation are relevant for persons who are exposed to an occupational context like nuclear industry workers. A historical cohort study was therefore conducted to examine mortality risks following occupational radiation exposure among 4,844 German nuclear power plant workers. This cohort included workers from ten nuclear power plants with an observational period from 1991 until 1997. The results of an enlarged cohort with 8,972 workers from all 17 nuclear power plants in West Germany are now available. During the extended follow-up period from 1991 to 2008, a total of 310 deaths among men were observed. The standardized mortality ratio (SMR) from all causes of deaths was estimated at 0.50 [95 % confidence interval (CI) 0.45-0.56]. A total of 126 deaths due to cancer occurred (SMR = 0.65; 95 % CI 0.51-0.82) and seven deaths due to leukemia (SMR = 1.23; 95 % CI 0.42-2.84). Overall, a reduced mortality compared to the general population of West Germany was observed indicating a healthy worker effect. In the dose-response analysis, no statistically significant risk due to ionizing radiation was seen. The hazard ratio (HR/mSv) for leukemia excluding chronic lymphocytic leukemia was estimated at 1.004 (95 % CI 0.997-1.011). In conclusion, the cohort is small and made up of young workers, most of whom were still employed at the end of the observational period in 2008. Results of the external analysis are difficult to interpret as influenced by a healthy worker effect. In the internal analysis, no excess of risk due to radiation was detected. (orig.)

  15. Integrated societal risk assessment framework for nuclear power and renewable energy sources

    Directory of Open Access Journals (Sweden)

    Sang Hun Lee

    2015-06-01

    Full Text Available Recently, the estimation of the social cost of energy sources has been emphasized as various novel energy options become feasible in addition to conventional ones. In particular, the social cost of introducing measures to protect power-distribution systems from power-source instability and the cost of accident-risk response for various power sources must be investigated. To account for these risk factors, an integrated societal risk assessment framework, based on power-uncertainty analysis and accident-consequence analysis, is proposed. In this study, we applied the proposed framework to nuclear power plants, solar photovoltaic systems, and wind-turbine generators. The required capacity of gas-turbine power plants to be used as backup power facilities to compensate for fluctuations in the power output from the main power source was estimated based on the performance indicators of each power source. The average individual health risk per terawatt-hours (TWh of electricity produced by each power source was quantitatively estimated by assessing accident frequency and the consequences of specific accident scenarios based on the probabilistic risk assessment methodology. This study is expected to provide insight into integrated societal risk analysis, and can be used to estimate the social cost of various power sources.

  16. Auxiliary feedwater system risk-based inspection guide for the Ginna Nuclear Power Plant

    International Nuclear Information System (INIS)

    Pugh, R.; Gore, B.F.; Vo, T.V.; Moffitt, N.E.

    1991-09-01

    In a study sponsored by the US Nuclear Regulatory Commission (NRC), Pacific Northwest Laboratory has developed and applied a methodology for deriving plant-specific risk-based inspection guidance for the auxiliary feedwater (AFW) system at pressurized water reactors that have not undergone probabilistic risk assessment (PRA). This methodology uses existing PRA results and plant operating experience information. Existing PRA-based inspection guidance information recently developed for the NRC for various plants was used to identify generic component failure modes. This information was then combined with plant-specific and industry-wide component information and failure data to identify failure modes and failure mechanisms for the AFW system at the selected plants. Ginna was selected as the eighth plant for study. The product of this effort is a prioritized listing of AFW failures which have occurred at the plant and at other PWRs. This listing is intended for use by NRC inspectors in the preparation of inspection plans addressing AFW risk-important components at the Ginna plant. 23 refs., 1 fig., 1 tab

  17. Demonstration of risk-based approaches to nuclear plant regulation

    International Nuclear Information System (INIS)

    Rahn, F.J.; Sursock, J.P.; Darling, S.S.; Oddo, J.M.

    1993-01-01

    This paper describes generic technical support EPRI is providing to the nuclear power industry relative to its recent initiatives in the area of risk-based regulations (RBR). A risk-based regulatory approach uses probabilistic risk assessment (PRA), or similar techniques, to allocate safety resources commensurate with the risk posed by nuclear plant operations. This approach will reduce O ampersand M costs, and also improve nuclear plant safety. In order to enhance industry, Nuclear Regulatory Commission (NRC) and public confidence in RBR, three things need to be shown: (1) manpower/resource savings are significant for both NRC and industry; (2) the process is doable in a reasonable amount of time; and (3) the process, if uniformly applied, results in demonstrably cheaper power and safer plants. In 1992, EPRI performed a qualitative study of the key RBR issues contributing to high O ampersand M costs. The results are given on Table 1. This study is being followed up by an in-depth quantitative cost/benefit study to focus technical work on producing guidelines/procedures for licensing submittals to NRC. The guidelines/procedures necessarily will be developed from successful demonstration projects such as the Fitzpatrick pilot plant study proposed by the New York Power Authority and other generic applications. This paper presents three examples: two motor operated valve projects performed by QUADREX Energy Services Corporation working with utilities in responding to NRC Generic Letter 89-10, and a third project working with Yankee Atomic Electric Company on service water systems at a plant in its service system. These demonstration projects aim to show the following: (1) the relative ease of putting together a technical case based on RBR concepts; (2) clarity in differentiating the various risk trade-offs, and in communicating overall reductions in risk with NRC; and (3) improved prioritization of NRC directives

  18. Configuration of risk monitor system by plant defense-in-depth risk monitor and reliability monitor

    International Nuclear Information System (INIS)

    Yoshikawa, Hidekazu; Lind Morten; Yang Ming; Hashim Muhammad; Zhang Zhijian

    2012-01-01

    A new method of risk monitor system of a nuclear power plant has been proposed from the aspect by what degree of safety functions incorporated in the plant system is maintained by multiple barriers of defense-in-depth (DiD). Wherein, the central idea is plant DiD risk monitor and reliability monitor derived from the five aspects of (1) design principle of nuclear safety based on DiD concept, (2) definition of risk and risk to be monitored, (3) severe accident phenomena as major risk, (4) scheme of risk ranking, and (5) dynamic risk display. In this paper, the overall frame of the proposed risk monitor system is summarized and the detailed discussion is made on major items such as definition of risk and risk ranking, anatomy of fault occurrence, two-layer configuration of risk monitor, how to configure individual elements of plant DiD risk monitor, and lastly how to apply for a PWR safety system. (author)

  19. Risks of turbine generators at WWER-440 nuclear power plants

    International Nuclear Information System (INIS)

    Virolainen, T.; Marttila, J.; Aulamo, H.

    1998-01-01

    Many serious fires and incidents have occurred in the turbine halls of nuclear power plants, resulting in serious damage and long shutdown outages. Some of these incidents have endangered the safe shutdown of the plants because of the location of lack of vital fire protection safety systems. A detailed analysis is necessary for all those plants that have equipment important for safe shutdown located in the turbine hall or its vicinity without strict fire separation by fire rated barriers. A reduction in the fire frequencies of the turbine hall is an additional way of improving safety. This is possible by improving all aspects of turbine generator operation. (author)

  20. The assessment of tornado missile hazard to nuclear power plants

    International Nuclear Information System (INIS)

    Goodman, J.; Koch, J.E.

    1983-01-01

    Numerical methods and computer codes for assessing tornado missile hazards to nuclear power plants are developed. Due to the uncertainty and randomness of tornado and tornado-generated missiles' characteristics, the damage probability of targets has a highly spread distribution. The proposed method is useful for assessing the risk of not providing protection to some nonsafety-related targets whose failure can create a hazard to the safe operation of nuclear power plants

  1. Industrial safety in power plants

    International Nuclear Information System (INIS)

    1987-01-01

    The proceedings of the VGB conference 'Industrial safety in power plants' held in the Gruga-Halle, Essen on January 21 and 22, 1987, contain the papers reporting on: Management responsibility for and legal consequences of industrial safety; VBG 2.0 Industrial Accident Prevention Regulation and the power plant operator; Operational experience gained with wet-type flue gas desulphurization systems; Flue gas desulphurization systems: Industrial-safety-related requirements to be met in planning and operation; the effects of the Hazardous Substances Ordinance on power plant operation; Occupational health aspects of heat-exposed jobs in power plants; Regulations of the Industrial Accident Insurance Associations concerning heat-exposed jobs and industrial medical practice; The new VBG 30 Accident Prevention Regulation 'Nuclear power plants'; Industrial safety in nuclear power plants; safe working on and within containers and confined spaces; Application of respiratory protection equipment in power plants. (HAG) [de

  2. Obligatory provisions for nuclear power plants

    International Nuclear Information System (INIS)

    Cloosters, W.

    2008-01-01

    To cover the expenses associated with decommissioning and disposal of their nuclear power plants, German nuclear power plant operators set aside a total of more than EUR 30 billion and entered the respective provisions into their balance sheets. One point of eminent importance in this regard is the question whether these provisions are adequate in amount and permitted under accounting and tax laws. The other point to be considered is whether the funds will be available reliably if and when needed. Against the backdrop of these issues, the practice and importance of making these provisions are described. This is followed by an outline of the basic accounting and taxation aspects. It is seen that obligations under public law can be the basis of financial provisions only if there is a obligation sufficiently concrete in terms of time and object. The following examination of applicable obligations under the Atomic Energy Act incumbent upon nuclear power plant operators with regard to decommissioning and disposal results in the finding that such obligations are only partly regulated in the Atomic Energy Act, and that specifications in terms of time and purpose are insufficient. If the national practice of making financial provisions is to be put on a reliable basis, it is recommended to express the law on decommissioning and its mode of financing in more concrete terms in the Atomic Energy Act. In addition to unequivocal decommissioning and disposal obligations, the Atomic Energy Act should also incorporate regulations about financial provisions for decomissioning which are in need of more precise language. The present practice of making provisions is characterized by the risk that the funds necessary for planned decommissioning and disposal may not be available when needed. It is against this background that possible solutions reducing that risk are discussed. A recommendation is expressed to establish a public fund for decommissioning and disposal to which the

  3. NUCLEAR POWER PLANT

    Science.gov (United States)

    Carter, J.C.; Armstrong, R.H.; Janicke, M.J.

    1963-05-14

    A nuclear power plant for use in an airless environment or other environment in which cooling is difficult is described. The power plant includes a boiling mercury reactor, a mercury--vapor turbine in direct cycle therewith, and a radiator for condensing mercury vapor. (AEC)

  4. Environmental impacts of nuclear and coal-fired power plants

    International Nuclear Information System (INIS)

    Horyna, J.; Horynova, H.

    1984-01-01

    The current situation in the development of nuclear power in the world and in Czechoslovakia is briefly outlined and the possibilities are discussed of alternative energy resources. The environmental impact is described of conventional power plants firing coal; sulphur and nitrogen oxides are mentioned and their environmental impacts shown. Their quantities and the quantities of other gaseous, liquid and soid wastes produced by coal power plants are given. Annual estimates are presented of radioactive material emissions; trace amount emissions of toxic metals and their ecological risks are shown. Concern over the increasing concentration of CO 2 in the atmosphere is voiced. For nuclear power plants, the amount of radionuclides in stack emission and of those released into water flows is tabulated. Their effect on the aqueous ecosystem is characterized as is thermal pollution of water flows and the environmental impact of cooling towers. Other factors are also mentioned, such as the increased industrial land use, the effect of high voltage transmission lines and aesthetic effects. The conclusion is arrived at that the construction of nuclear power plants will eliminate the adverse environmental impact of emissions while the other impacts of the two types of power plants are comparable. (A.K.)

  5. Risk informed analysis of training effectiveness for mitigating accidents of nuclear power plants

    International Nuclear Information System (INIS)

    Lee, Chang Ju

    2012-01-01

    A critical area for deriving expected benefits from training and exercise is the measurement of 'training effectiveness'-how well the training inputs are serving the intended purpose. This aspect is often neglected by nuclear organizations, saying that measurement is difficult. However, I believe that a technique in nuclear society has developed sufficiently to measure most important aspects of training by way of human reliability analysis (HRA) used in probabilistic safety assessment (PSA) of nuclear power plants (NPPs). The consequences of errors caused by lack of training can be evaluated in terms of the overall vulnerability to human error of the facility under consideration. This study presents current situation and considerations for measures of robustness on nuclear accidents and HRA technique on the training effectiveness. In view of risk informed approach with this consideration and an example case, I'd like to identify appropriate relationship between risk measures of robustness and training effectiveness

  6. The marketing concept of nuclear power plant constructors

    International Nuclear Information System (INIS)

    Czakainski, M.

    1980-01-01

    The paper examines the largely non-investigated area of marketing theory and energy sciences. The author considers the structure of the nuclear power industry and of marketing, analyses the nuclear power station market and its factors of influence, and gives a market forecast. The marketing concept requires especially a typologization of the investment good nuclear power plant. Project-dependent and project-independent marketing activities are coordinated in a marketing programme, and are integrated into mixed marketing efforts. Problems result from insecurity related to the further development of political, social and economic factors of influence. Constructors of nuclear power plants in the Federal Republic of Germany have to adapt to this insecurity and to face risks presented by entrepreneurial activities and the environment by means of flexible planning. (HSCH) [de

  7. Studies on environment safety and application of advanced reactor for inland nuclear power plants

    International Nuclear Information System (INIS)

    Wei, L.; Jie, L.

    2014-01-01

    To study environment safety assessment of inland nuclear power plants (NPPs), the impact of environment safety under the normal operation was researched and the environment risk of serious accidents was analyzed. Moreover, the requirements and relevant provisions of site selection between international nuclear power plant and China's are comparatively studied. The conclusion was that the environment safety assessment of inland and coastal nuclear power plant have no essential difference; the advanced reactor can meet with high criteria of environment safety of inland nuclear power plants. In this way, China is safe and feasible to develop inland nuclear power plant. China's inland nuclear power plants will be as big market for advanced reactor. (author)

  8. Nuclear power. Volume 1. Nuclear power plant design

    International Nuclear Information System (INIS)

    Pedersen, E.S.

    1978-01-01

    NUCLEAR POWER PLANT DESIGN is intended to be used as a working reference book for management, engineers and designers, and as a graduate-level text for engineering students. The book is designed to combine theory with practical nuclear power engineering and design experience, and to give the reader an up-to-date view of the status of nuclear power and a basic understanding of how nuclear power plants function. Volume 1 contains the following chapters; (1) nuclear reactor theory; (2) nuclear reactor design; (3) types of nuclear power plants; (4) licensing requirements; (5) shielding and personnel exposure; (6) containment and structural design; (7) main steam and turbine cycles; (8) plant electrical system; (9) plant instrumentation and control systems; (10) radioactive waste disposal (waste management) and (11) conclusion

  9. Power plants 2010. Lectures

    International Nuclear Information System (INIS)

    2010-01-01

    The proceedings include the following lectures: Facing the challenges - new structures for electricity production. Renewable energies in Europe - chances and challenges. Nuclear outlook in the UK. Sustainable energy for Europe. Requirements of the market and the grid operator at the electricity production companies. Perspectives for the future energy production. Pumped storage plants - status and perspectives. Nuclear power/renewable energies -partners or opponents? New fossil fired power stations in Europe - status and perspectives. Nuclear energy: outlook for new build and lifetime extension in Europe. Biomass in the future European energy market - experiences for dong energy. Meeting the EU 20:20 renewable energy targets: the offshore challenges. DESERTEC: sustainable electricity for Europe, Middle East and North Africa. New power plants in Europe - a challenge for project and quality management. Consideration of safely in new build activities of power plants. Challenges to an integrated development in Maasvlakte, Netherlands. Power enhancement in EnBW power plants. Operational experiences of CCS pilot plants worldwide. Two years of operational experiences with Vattenfall's oxyfuel pilot plant. Pre-conditions for CCS. Storage technologies for a volatile generation. Overview: new generation of gas turbines.

  10. The year 2000 power plant

    International Nuclear Information System (INIS)

    Roman, H.T.

    1989-01-01

    Every utility seeks extended service life from its existing power plants before building new ones. It is not easy to justify a new power plant. The licensing and cost of new plants have become uncertain. In response to these conditions, electric utilities are undertaking plant life-extension studies and, in some cases, reconditioning/upgrading old power plants to significantly increase useful service life. Other technologies like robotics and artificial intelligence/expert systems are also being developed to reduce operating and maintenance (O and M) expenses, to remove workers from potentially hazardous environments, and to reduce plant downtime. Together, these steps represent an interim solution, perhaps providing some relief for the next few decades. However, there are serious physical and economic limits to retrofitting new technology into existing power plants. Some old plants will simply be beyond their useful life and require retirement. In nuclear plants, for instance, retrofit may raise important and time-consuming licensing/safety issues. Based on their robotics and artificial intelligence experience, the authors of this article speculate bout the design of the year 2000 power plant - a power plant they feel will naturally incorporate liberal amounts of robotic and artificial intelligence technologies

  11. Economic risks of nuclear power reactor accidents

    International Nuclear Information System (INIS)

    Burke, R.P.; Aldrich, D.C.

    1984-04-01

    Models to be used for analyses of economic risks from events which occur during US LWR plant operation are developed in this study. The models include capabilities to estimate both onsite and offsite costs of LWR events ranging from routine plant forced outages to severe core-melt accidents resulting in large releases of radioactive material to the environment. The models have been developed for potential use by both the nuclear power industry and regulatory agencies in cost/benefit analyses for decision-making purposes. The new onsite cost models estimate societal losses from power production cost increases, plant capital losses, plant decontamination costs, and plant repair costs which may be incurred after LWR operational events. Early decommissioning costs, plant worker health impact costs, electric utility business costs, nuclear power industry costs, and litigation costs are also addressed. The newly developed offsite economic consequence models estimate The costs of post-accident population protective measures and public health impacts. The costs of population evacuation and temporary relocation, agricultural product disposal, land and property decontamination, and land interdiction are included in the economic models for population protective measures. Costs of health impacts and medical care costs are also included in the models

  12. Estimation of environmental external costs between coal fired power plant and nuclear power plant

    International Nuclear Information System (INIS)

    Moon, G. H.; Kim, S. S.

    2000-01-01

    First of all, this study evaluated the impacts on the health and the environment of air pollutants emitted from coal power plant and nuclear power pant, two major electric power generating options in Korea. Then, the environmental external costs of those two options were estimated by transforming the health and environment impact into monetary values. To do this, AIRPACTS and Impacts of Atmospheric Release model developed by IAEA were used. The environmental external cost of Samcheonpo coal power plant was estimated about 25 times as much as that of Younggwang nuclear power plant. This result implies that nuclear power plant is a clean technology compared with coal power plant. This study suggests that the external cost should be reflected in the electric system expansion plan in order to allocate energy resources efficiently and to reduce economic impact stemming from the environmental regulation emerged recently on a global level

  13. Organization patterns of PWR power plants

    International Nuclear Information System (INIS)

    Leicman, J.

    1980-01-01

    Organization patterns are shown for the St. Lucia 1, North Anna, Sequoyah, and Beaver Valley nuclear power plants, for a typical PWR power plant in the USA, for the Biblis/RWE-KWU nuclear power plants and for a four-unit nuclear power plant operated by Electricite de France as well as for the Loviisa power plant. Organization patterns are also shown for relatively independent and non-independent nuclear power plants according to IAEA recommendations. (J.P.)

  14. Nuclear power plant siting

    International Nuclear Information System (INIS)

    Sulkiewicz, M.; Navratil, J.

    The construction of a nuclear power plant is conditioned on territorial requirements and is accompanied by the disturbance of the environment, land occupation, population migration, the emission of radioactive wastes, thermal pollution, etc. On the other hand, a nuclear power plant makes possible the introduction of district heating and increases the economic and civilization activity of the population. Due to the construction of a nuclear power plant the set limits of negative impacts must not be exceeded. The locality should be selected such as to reduce the unfavourable effects of the plant and to fully use its benefits. The decision on the siting of the nuclear power plant is preceded by the processing of a number of surveys and a wide range of documentation to which the given criteria are strictly applied. (B.H.)

  15. Risk of Thyroid Cancer after the Fukushima Nuclear Power Plant Accident

    International Nuclear Information System (INIS)

    Yamashita, S.

    2016-01-01

    Full text: A sound scientific understanding about the relationship between radiation dose and health risk is needed to apply any countermeasure against radiological and nuclear accidents. Since the Great East Japan earthquake and the Fukushima Daiichi Nuclear Power Plant accident in Japan, Fukushima Prefecture has started the Fukushima Health Management Survey Project since June 2011 for the purpose of long-term health care administration for the prefectural residents. There are considerable differences between Chernobyl and Fukushima regarding radiation dose to the public, however, it is still difficult to estimate retrospectively accurate internal exposure dose individually from the short-lived radioactive iodines. Another difficult challenge is to how to manage non-radiation–related health effects, such as post-disaster mental impact and lifestyle changes. As we support residents in their recovery and return to their homes, understanding each individual’s state with respect to radiation and regular monitoring of their health conditions contribute to the region’s rebirth and restoration. Therefore, as one of the tools of risk communication, the necessity of thyroid ultrasound examination in Fukushima and the intermediate results of this survey targeting children will be reviewed and discussed in order to avoid any misunderstanding or misinterpretation of the high detection rate of childhood and adolescent thyroid cancer by mass screening. (author

  16. Central receiver solar thermal power system, Phase 1. CDRL item 2. Pilot plant preliminary design report. Volume VI. Electrical power generation and master control subsystems and balance of plant

    Energy Technology Data Exchange (ETDEWEB)

    Hallet, Jr., R. W.; Gervais, R. L.

    1977-10-01

    The requirements, performance, and subsystem configuration for both the Commercial and Pilot Plant electrical power generation subsystems (EPGS) and balance of plants are presented. The EPGS for both the Commercial Plant and Pilot Plant make use of conventional, proven equipment consistent with good power plant design practices in order to minimize risk and maximize reliability. The basic EPGS cycle selected is a regenerative cycle that uses a single automatic admission, condensing, tandem-compound double-flow turbine. Specifications, performance data, drawings, and schematics are included. (WHK)

  17. Some insights from fire risk analysis of US nuclear power plants

    International Nuclear Information System (INIS)

    Kazarians, M.; Lambright, J.A.; Frank, M.V.

    1998-01-01

    Fire risk analysis has been conducted for a significant portion of the nuclear power plants in the U.S. using either Probabilistic Risk Assessments (PRAs) or FIVE or a combination of the two methodologies. Practically all fire risk studies have used step-wise, screening approach. To establish the contents of a compartment, the cable routing information collected for Appendix R compliance have been used in practically all risk studies. In several cases, the analysts have gone beyond the Appendix R and have obtained the routing of additional cables. For fire impact analysis typically an existing PRA model is used. For fire frequencies, typically, a generic data base is used. Fire scenarios are identified in varying levels of detail. The most common approach, in the early stages of screening, is based on the assumption that given a fire, the entire contents of the compartment are lost. Less conservative scenarios are introduced at later stages of the analysis which may include fire propagation patterns, fires localized to an item. and suppression of the fire before critical damage. For fire propagation and damage analysis, a large number of studies have used FIVE and many have used COMPBRN. For detection and suppression analysis, the generic suppression system unavailabilities given in FIVE have been used. The total core damage frequencies typically range between 1x10 -6 to 1x10 -4 per year. Control rooms and cable spreading rooms are the two most common areas found to be significant contributors to fire risk. Other areas are mainly from the Auxiliary Building (in the case of PWRs) and Reactor Building (in the case of BWRs). Only in one case, the main contributor to fire is the turbine building, which included several safety related equipment and cables. (author)

  18. Business interruption and loss of assets risk assessment in support of the design of an innovative concentrating solar power plant

    International Nuclear Information System (INIS)

    Amato, Andrea; Gallisto, Maurizio; Maccari, Augusto; Paganelli, Mauro; Compare, Michele; Zio, Enrico

    2011-01-01

    Concentrating Solar Power (CSP) plants are a promising technology of renewable energy production, as witnessed by the increasing public and private investments during the last decade. The assessment of the associated risks of business interruption (loss of production) and loss of assets due to the occurrence of undesired internal or external events, such as failures of components, unfavorable environmental conditions, etc., brings added values by informing design modifications and contributing to production assurance, for rational Company investments in these environmentally sustainable power plants. This work presents and applies a methodology for assessing the risks associated to a CSP of innovative design. The methodology is derived from traditional system risk analysis, specifically focused only on the economic consequences of the internal events of failure behavior of components. The innovation in the design considered is particularly aimed at augmenting the CSP intrinsic capability of being equipped with thermal storage systems by the introduction of a molten salt mixture as heat transfer fluid. This technology presents evident advantages in terms of system simplification and reduction of production costs but on the other hand introduces a risk factor with regards to the solidification of the salt mixture that occurs at about 240 C. (author)

  19. Stochastic Drought Risk Analysis and Projection Methods For Thermoelectric Power Systems

    Science.gov (United States)

    Bekera, Behailu Belamo

    Combined effects of socio-economic, environmental, technological and political factors impact fresh cooling water availability, which is among the most important elements of thermoelectric power plant site selection and evaluation criteria. With increased variability and changes in hydrologic statistical stationarity, one concern is the increased occurrence of extreme drought events that may be attributable to climatic changes. As hydrological systems are altered, operators of thermoelectric power plants need to ensure a reliable supply of water for cooling and generation requirements. The effects of climate change are expected to influence hydrological systems at multiple scales, possibly leading to reduced efficiency of thermoelectric power plants. This study models and analyzes drought characteristics from a thermoelectric systems operational and regulation perspective. A systematic approach to characterize a stream environment in relation to extreme drought occurrence, duration and deficit-volume is proposed and demonstrated. More specifically, the objective of this research is to propose a stochastic water supply risk analysis and projection methods from thermoelectric power systems operation and management perspectives. The study defines thermoelectric drought as a shortage of cooling water due to stressed supply or beyond operable water temperature limits for an extended period of time requiring power plants to reduce production or completely shut down. It presents a thermoelectric drought risk characterization framework that considers heat content and water quantity facets of adequate water availability for uninterrupted operation of such plants and safety of its surroundings. In addition, it outlines mechanisms to identify rate of occurrences of the said droughts and stochastically quantify subsequent potential losses to the sector. This mechanism is enabled through a model based on compound Nonhomogeneous Poisson Process. This study also demonstrates how

  20. A method for systematic resource allocation for improved nuclear power plant performance

    International Nuclear Information System (INIS)

    Doboe, L.; Golay, M.; Todreas, N.; Li, F.

    2000-01-01

    An investigation was made on plant improvement investments in terms of the methods and criteria used in cooperation with the staffs of a group of nuclear power plants, aiming to understand better the methods used within US nuclear power plants for allocating investments. Cost analyses were being used the authors translated the process into a mathematical format. A spectrum of practices, ranging from use of informal power relationship-based processes to format benefit was found among different organizations. Cost-based processes structured to take into account a broad range of decision factors. Factors such as cost results, risk aversion and required uncertainty premiums were included in the treatment. Ultimately, competing investments can be ranked using the method presented in order of their return upon investment at an equivalent level of uncertainty. A method for ranking the attractiveness of nuclear power plant investments is presented which takes into account consistently factors of return upon investment, uncertainty and decision-maker risk aversion. Hopefully its use will result in improved decisions. (M.N.)

  1. THE LOCAL IMPACTS OF MERCURY EMISSIONS FROM COAL FIRED POWER PLANTS ON HUMAN HEALTH RISK. PROGRESS REPORT FOR THE PERIOD OF MARCH 2003 - MARCH 2003.

    Energy Technology Data Exchange (ETDEWEB)

    SULLIVAN,T.M.LIPFERT,F.D.MORRIS,S.M.

    2003-05-01

    This report presents a follow-up to previous assessments of the health risks of mercury that BNL performed for the Department of Energy. Methylmercury is an organic form of mercury that has been implicated as the form of mercury that impacts human health. A comprehensive risk assessment report was prepared (Lipfert et al., 1994) that led to several journal articles and conference presentations (Lipfert et al. 1994, 1995, 1996). In 2001, a risk assessment of mercury exposure from fish consumption was performed for 3 regions of the U.S (Northeast, Southeast, and Midwest) identified by the EPA as regions of higher impact from coal emissions (Sullivan, 2001). The risk assessment addressed the effects of in utero exposure to children through consumption of fish by their mothers. Two population groups (general population and subsistence fishers) were considered. Three mercury levels were considered in the analysis, current conditions based on measured data, and hypothetical reductions in Hg levels due to a 50% and 90% reduction in mercury emissions from coal fired power plants. The findings of the analysis suggested that a 90% reduction in coal-fired emissions would lead to a small reduction in risk to the general population (population risk reduction on the order of 10{sup -5}) and that the population risk is born by less than 1% of the population (i.e. high end fish consumers). The study conducted in 2001 focused on the health impacts arising from regional deposition patterns as determined by measured data and modeling. Health impacts were assessed on a regional scale accounting for potential percent reductions in mercury emissions from coal. However, quantitative assessment of local deposition near actual power plants has not been attempted. Generic assessments have been performed, but these are not representative of any single power plant. In this study, general background information on the mercury cycle, mercury emissions from coal plants, and risk assessment are

  2. Design of comprehensive plant information system considering maintenance indicators in nuclear power plant

    International Nuclear Information System (INIS)

    Takata, Takashi; Yamaguchi, Akira; Yamamoto, Akio

    2013-01-01

    A safety of a nuclear power plant must be ensured and maintained through its entire plant life. For this plant life cycle safety (PLCS), a comprehensive plant information system, in which an each maintenance record of the plant is taken into consideration, is of importance. In this paper, a development of a plant chart, which is a part of the information system, has been developed based on a defense-in-depth concept that is one of the most important concept to ensure the plant safety. In the chart, an updated probability of loss of a component or function is used as a maintenance indicator and a probabilistic risk assessment (PRA) method is applied to quantify the plant status in the chart. (author)

  3. Auxiliary feedwater system risk-based inspection guide for the North Anna nuclear power plants

    International Nuclear Information System (INIS)

    Nickolaus, J.R.; Moffitt, N.E.; Gore, B.F.; Vo, T.V.

    1992-10-01

    In a study sponsored by the US Nuclear regulatory Commission (NRC), Pacific Northwest Laboratory has developed and applied a methodology for deriving plant-specific risk-based inspection guidance for the auxiliary feedwater (AFW) system at pressurized water reactors that have not undergone probabilistic risk assessment (PRA). This methodology uses existing PRA results and plant operating experience information. Existing PRA-based inspection guidance information recently developed for the NRC for various plants was used to identify generic component failure modes. This information was then combined with plant-specific and industry-wide component information and failure data to identify failure modes and failure mechanisms for the AFW system at the selected plants. North Anna was selected as a plant for study. The product of this effort is a prioritized listing of AFW failures which have occurred at the plant and at other PWRs. This listing is intended for use by the NRC inspectors in preparation of inspection plans addressing AFW risk important components at the North Anna plant

  4. Changes in attitude structure toward nuclear power in the nuclear power plant locations of Tohoku district

    International Nuclear Information System (INIS)

    Tsujikawa, Norifumi; Tsuchida, Shoji; Shiotani, Takamasa; Nakagawa, Yuri

    2012-01-01

    This survey was examined the changes in structure of attitude toward nuclear power and the influence of environmental value on the attitude structure before and after the accident at the Fukushima No. 1 nuclear power plant. With residents of Aomori, Miyagi, and Fukushima prefectures as participants, we conducted online surveys in November 2009 and October 2011. Comparing the results before and after the accident, we found that trust in the management of nuclear power plants had a stronger influence on the perceived risk and benefit regarding nuclear power after the accident than before the accident. The value of concern about environmental destruction resulted in reduced trust in the management. (author)

  5. Shutdown and low-power operation at commercial nuclear power plants in the United States

    International Nuclear Information System (INIS)

    1993-09-01

    The report contains the results of the NRC Staff's evaluation of shutdown and low-power operations at US commercial nuclear power plants. The report describes studies conducted by the staff in the following areas: Operating experience related to shutdown and low-power operations, probabilistic risk assessment of shutdown and low-power conditions and utility programs for planning and conducting activities during periods the plant is shut down. The report also documents evaluations of a number of technical issues regarding shutdown and low-power operations performed by the staff, including the principal findings and conclusions. Potential new regulatory requirements are discussed, as well as potential changes in NRC programs. A draft report was issued for comment in February 1992. This report is the final version and includes the responses to the comments along with the staff regulatory analysis of potential new requirements

  6. Study of a simplified method of evaluating the economic maintenance importance of components in nuclear power plant system

    International Nuclear Information System (INIS)

    Aoki, Takayuki; Takagi, Toshiyuki; Kodama, Noriko

    2014-01-01

    Safety risk importance of components in nuclear power plants has been evaluated based on the probabilistic risk assessment and used for the decisions in various plant managements. But economic risk importance of the components has not been discussed very much. Therefore, this paper discusses risk importance of the components from the viewpoint of plant economic efficiency and proposes a simplified evaluation method of the economic risk importance (or economic maintenance importance). As a result of consideration, the followings were obtained. (1) A unit cost of power generation is selected as a performance indicator and can be related to a failure rate of components in nuclear power plant which is a result of maintenance. (2) The economic maintenance importance has to major factors, i.e. repair cost at component failure and production loss associated with plant outage due to component failure. (3) The developed method enables easy understanding of economic impacts of plant shutdown or power reduction due to component failures on the plane which adopts the repair cost in vertical axis and the production loss in horizontal axis. (author)

  7. Images of nuclear power plants

    International Nuclear Information System (INIS)

    Hashiguchi, Katsuhisa; Misumi, Jyuji; Yamada, Akira; Sakurai, Yukihiro; Seki, Fumiyasu; Shinohara, Hirofumi; Misumi, Emiko; Kinjou, Akira; Kubo, Tomonori.

    1995-01-01

    This study was conducted to check and see, using Hayashi's quantification method III, whether or not the respondents differed in their images of a nuclear power plant, depending on their demographic variables particularly occupations. In our simple tabulation, we compared subject groups of nuclear power plant employees with general citizens, nurses and students in terms of their images of a nuclear power plant. The results were that while the nuclear power plant employees were high in their evaluations of facts about a nuclear power plant and in their positive images of a nuclear power plant, general citizens, nurses and students were overwhelmingly high in their negative images of a nuclear power plant. In our analysis on category score by means of the quantification method III, the first correlation axis was the dimension of 'safety'-'danger' and the second correlation axis was the dimension of 'subjectivity'-'objectivity', and that the first quadrant was the area of 'safety-subjectivity', the second quadrant was the area of 'danger-subjectivity', the third quadrant as the area of 'danger-objectivity', and the forth quadrant was the area of 'safety-objectivity'. In our analysis of sample score, 16 occupation groups was compared. As a result, it was found that the 16 occupation groups' images of a nuclear power plant were, in the order of favorableness, (1) section chiefs in charge, maintenance subsection chiefs, maintenance foremen, (2) field leaders from subcontractors, (3) maintenance section members, operation section members, (4) employees of those subcontractors, (5) general citizens, nurses and students. On the 'safety-danger' dimension, nuclear power plant workers on the one hand and general citizens, nurses and students on the other were clearly divided in terms of their images of a nuclear power plant. Nuclear power plant workers were concentrated in the area of 'safety' and general citizens, nurses and students in the area of 'danger'. (J.P.N.)

  8. GLObal RIsk MANagement system for plant operations GLORIMAN

    International Nuclear Information System (INIS)

    Silverman, Eugene B.

    2004-01-01

    Considerable effort has been expended by nuclear power plants in the preparation of their Independent Plant Evaluation (IPE) programs. The result of these projects is the generation of very useful information concerning plant operations, states, availability and risk. The potential application of this information is often unrealized due to the unwieldy form of the data as reported in the IPE. Plant personnel would benefit greatly from quick access to risk information as a means of supporting day-to-day decisions, but the information exists only in a difficult to understand and inaccessible form. There is a need to translate the costs invested in Probabilistic Risk Assessment (PRA) projects into a useable tool for plant personnel. This paper describes a software tool developed by ARD Corporation to be used by plants to assist in determining the operational risks and benefits associated with modifying the plant state during normal and off-normal operations for performing maintenance. This tool integrates a relational database with an easy-to-use graphical user interface and several unique software features. The result is a responsive, easy-to-understand tool that integrates an organization's PRA/IPE into the operational and maintenance needs of the station. The Global Risk Management System is designed to allow the user to evaluate the risk associated with current and proposed plant states. The impact of changes in plant configuration, operational modes and equipment availability are assessed from a risk management perspective, but displayed in an easy-to-understand form for personnel not familiar with risk methodology. Additionally, pipe and instrumentation drawings can be retrieved by the user and displayed as a reference tool. (author)

  9. Mitigation of Hydrogen Hazards in Severe Accidents in Nuclear Power Plants

    International Nuclear Information System (INIS)

    2011-07-01

    Consideration of severe accidents in nuclear power plants is an essential component of the defence in depth approach in nuclear safety. Severe accidents have very low probabilities of occurring, but may have significant consequences resulting from the degradation of nuclear fuel. The generation of hydrogen and the risk of hydrogen combustion, as well as other phenomena leading to overpressurization of the reactor containment in case of severe accidents, represent complex safety issues in relation to accident management. The combustion of hydrogen, produced primarily as a result of heated zirconium metal reacting with steam, can create short term overpressure or detonation forces that may exceed the strength of the containment structure. An understanding of these phenomena is crucial for planning and implementing effective accident management measures. Analysis of all the issues relating to hydrogen risk is an important step for any measure that is aimed at the prevention or mitigation of hydrogen combustion in reactor containments. The main objective of this publication is to contribute to the implementation of IAEA Safety Standards, in particular, two IAEA Safety Requirements: Safety of Nuclear Power Plants: Design and Safety of Nuclear Power Plants: Operation. These Requirements publications discuss computational analysis of severe accidents and accident management programmes in nuclear power plants. Specifically with regard to the risk posed by hydrogen in nuclear power reactors, computational analysis of severe accidents considers hydrogen sources, hydrogen distribution, hydrogen combustion and control and mitigation measures for hydrogen, while accident management programmes are aimed at mitigating hydrogen hazards in reactor containments.

  10. Small hydroelectric power plants

    International Nuclear Information System (INIS)

    Helgesen, Boerre

    2002-01-01

    Small hydroelectric power plants are power plants of 1 - 10 MW. For a supplier, this is an unnatural limit. A more natural limit involves compact engine design and simplified control system. The article discusses most of the engine and electrotechnical aspects in the development, construction and operation of such a plant

  11. The Kuroshio power plant

    CERN Document Server

    Chen, Falin

    2013-01-01

    By outlining a new design or the Kuroshio power plant, new approaches to turbine design, anchorage system planning, deep sea marine engineering and power plant operations and maintenance are explored and suggested. The impact on the local environment, particularly in the face of natural disasters, is also considered to provide a well rounded introduction to plan and build a 30MW pilot power plant. Following a literature review, the six chapters of this book propose a conceptual design by focusing on the plant's core technologies and establish the separate analysis logics for turbine design and

  12. A study on risk perception toward nuclear power operation in Taiwan

    International Nuclear Information System (INIS)

    Lee Ciao-tzu; Hu Shiang-ling; Chang, Wushou P.

    2000-01-01

    Currently, more conflicts appear between the public and government over the establishment of the 4th nuclear power plant in Taiwan. In order to improve risk management by the Society, understanding the risk perception of the public will be essential. A pilot study on the risk perception toward nuclear power operation and other current risks was conducted in summer of 1999. In addition to perception towards nuclear power operation, the survey evaluated several dimensions of health-related risks including smoking, chemical wastes, nuclear wastes, air transportation, AIDS, and food intoxication. The questionnaire was designed to be proceeded under systemic instruction and followed with self-filling. 57 (85.1%) of 67 respondents worked at the Taipei Metropolitan Rapid Transportation, including 62 male subjects (92.5%). 44 (69.8%) respondents favored building the 4th nuclear power plant in Taiwan. The acceptable distance between their houses and the nuclear power plant was 145.13 km in average, as compared with 400 km that of North and South of Taiwan. The mean expenses they are willing to pay to reduce the risk of the NPP is about US $7.73, 0.56% of their average income. However, the levels of risks toward nuclear power operation is significant higher than these for air transportation, smoking, and food intoxication. Government's spending is assumed more effective to reduce the threats from risks of nuclear power operation, rather than professional's or experts' effects. Besides, other related factors include levels of involuntary exposure to NP operation (p<0.001) and number of people potentially in danger (p<0.001). These 2 altitudes are positively correlated with the respondents' perceived risks. Different attitudes toward NP operation within these engineers, and those evaluated by others, are of great interest. Further evaluation will be conducted to compare the mechanism involved. We gratefully acknowledge financial support from the National Science Council

  13. A study on risk perception toward nuclear power operation in Taiwan

    Energy Technology Data Exchange (ETDEWEB)

    Lee Ciao-tzu; Hu Shiang-ling; Chang, Wushou P. [National Yang-Ming University, Taiwan (China)

    2000-05-01

    Currently, more conflicts appear between the public and government over the establishment of the 4th nuclear power plant in Taiwan. In order to improve risk management by the Society, understanding the risk perception of the public will be essential. A pilot study on the risk perception toward nuclear power operation and other current risks was conducted in summer of 1999. In addition to perception towards nuclear power operation, the survey evaluated several dimensions of health-related risks including smoking, chemical wastes, nuclear wastes, air transportation, AIDS, and food intoxication. The questionnaire was designed to be proceeded under systemic instruction and followed with self-filling. 57 (85.1%) of 67 respondents worked at the Taipei Metropolitan Rapid Transportation, including 62 male subjects (92.5%). 44 (69.8%) respondents favored building the 4th nuclear power plant in Taiwan. The acceptable distance between their houses and the nuclear power plant was 145.13 km in average, as compared with 400 km that of North and South of Taiwan. The mean expenses they are willing to pay to reduce the risk of the NPP is about US $7.73, 0.56% of their average income. However, the levels of risks toward nuclear power operation is significant higher than these for air transportation, smoking, and food intoxication. Government's spending is assumed more effective to reduce the threats from risks of nuclear power operation, rather than professional's or experts' effects. Besides, other related factors include levels of involuntary exposure to NP operation (p<0.001) and number of people potentially in danger (p<0.001). These 2 altitudes are positively correlated with the respondents' perceived risks. Different attitudes toward NP operation within these engineers, and those evaluated by others, are of great interest. Further evaluation will be conducted to compare the mechanism involved. We gratefully acknowledge financial support from the National

  14. The public opinion on emergency preparedness close to nuclear power plants

    International Nuclear Information System (INIS)

    Hultaaker, Oe.

    1984-07-01

    More than 1500 people have been interviewed on their attitudes towards and their knowledge of emergency actions on nuclear accidents at nuclear power plants. Of the people addressed, 768 lived in the inner zones close to the power plants. 775 were farmers near the four nuclear power sites in Sweden. The farmers lived both in inner zones and zones further away. A majority consider themselves not well-informed on health risks after a nuclear accident. More than a third would want more information on what to do in case of accident. Farmers outside the inner zones are more dissatisfied with the information status than other groups. Farmers from the inner zones consider the information given inadequate regarding risks to their health and also health risks for their live stock. The results of interviews are in some cases compared with the information given to the public. (Aa)

  15. Risk-based assessment of the allowable outage times for the unit 1 leningrad nuclear power plant ECCS components

    International Nuclear Information System (INIS)

    Koukhar, Sergey; Vinnikov, Bronislav

    2009-01-01

    Present paper describes a method for risk - informed assessment of the Allowable Outage Times (AOTs). The AOT is the time, when components of a safety system allowed to be out of service during power operation or during shutdown operation off a plant. If the components are not restored during the time, the plant in operation must be shut down or the plant in a given shutdown mode has to go to safer shutdown mode. Application of the method is also provided for the equipment of the Unit 1 Leningrad NPP ECCS components. For solution of the problem it is necessary to carry out two series of computations using a Living PSA model, level 1. In the first series of the computations the core damage frequency (CDFb) for the base configuration of the plant is determined (there is no equipment out of service). Here the symbol 'b' means the base configuration of a plant. In the second series of the computations the core damage frequency (CDFi) for the configuration of the plant with the component (which is out of service) is calculated. That is here CDFi is determined for the failure probability of the component equal to 1.0 (component 'i' is unavailable). Then it is necessary to determine so called Risk Increase Factor (RIF) using the following ratio: RIFi = CDFi / CDFb. At last the AOT is calculated with the help of the ratio: AOTi = Tppr / RIFi, where Tppr is a period of time between two Planned Preventive Repairs (PPRs). 1. Using the risk based approach the AOTs were calculated for a set of the components of the Unit 1 Leningrad NPP ECCS components. 2. The main conclusion from the analysis is that the current deterministic AOTs for the ECCS components are conservative and should be extended. 3. The risk based extension of the AOTs for the ECCS components can prevent the Unit 1 Leningrad NPP to enter into the operating modes with increased risk. (author)

  16. The human contribution to nuclear power plant emergencies

    International Nuclear Information System (INIS)

    Reason, J.

    1987-01-01

    The safety of present and future nuclear power plants is considered, with particular reference to the human components of these plants. The approach by the United Kingdom Nuclear Installations Inspectorate is particularly criticised. In particular, objections are made to the use of event and fault tree analyses. The UK NII have also decided that comprehensive quantification of human reliability is not feasible. However, figures presented show that the human contribution to monitored power plant emergencies is high, by far the greatest proportion of root causes of emergencies were attributable to human performance. The origins of, and problems with, 'principle 124' are discussed. Automatic safety systems are also distrusted. Current probabilistic risk assessment and probabilistic safety analysis is seen as an unsatisfactory basis for the setting of safety targets. (UK)

  17. Technology Trend in the Maintenance of Nuclear Power Plants

    International Nuclear Information System (INIS)

    Yoon, Kyungsup; Lee, Unjang

    2014-01-01

    In this paper, overall technology evolution is reviewed and the improvements in the plant safety, reliability and productivity are described. And the issue and some recommendation for better maintenance of Korean nuclear power plants are presented as the interim study results on the 'Management and Regulatory Policy for the Nuclear Power Plant Maintenance and Equipment Reliability' under the agreement with the Nuclear Safety and Security Commission. The future trend in the maintenance technologies is also covered. Maintenance is the essential element for the enhancement of plant safety, reliability and economics and also for public safety. Therefore the regulator's involvements and the utility's active participation is inevitable for the better maintenance. For the better sustainability of our nuclear power plants the followings are recommended. ·Establishment of the good maintenance program and continuous improvement. ·Application of OLM on the safety related and non-safety related components by step-by-step approach. ·Improvement PRA technology for the accurate and reliable risk analysis. ·Continuous training and cultivation for the qualified maintenance personnel

  18. Technology Trend in the Maintenance of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Kyungsup; Lee, Unjang [CTO and CEO, Seoul (Korea, Republic of)

    2014-05-15

    In this paper, overall technology evolution is reviewed and the improvements in the plant safety, reliability and productivity are described. And the issue and some recommendation for better maintenance of Korean nuclear power plants are presented as the interim study results on the 'Management and Regulatory Policy for the Nuclear Power Plant Maintenance and Equipment Reliability' under the agreement with the Nuclear Safety and Security Commission. The future trend in the maintenance technologies is also covered. Maintenance is the essential element for the enhancement of plant safety, reliability and economics and also for public safety. Therefore the regulator's involvements and the utility's active participation is inevitable for the better maintenance. For the better sustainability of our nuclear power plants the followings are recommended. ·Establishment of the good maintenance program and continuous improvement. ·Application of OLM on the safety related and non-safety related components by step-by-step approach. ·Improvement PRA technology for the accurate and reliable risk analysis. ·Continuous training and cultivation for the qualified maintenance personnel.

  19. Economics of hybrid photovoltaic power plants

    Energy Technology Data Exchange (ETDEWEB)

    Breyer, Christian

    2012-08-16

    The global power supply stability is faced to several severe and fundamental threats, in particular steadily increasing power demand, diminishing and degrading fossil and nuclear energy resources, very harmful greenhouse gas emissions, significant energy injustice and a structurally misbalanced ecological footprint. Photovoltaic (PV) power systems are analysed in various aspects focusing on economic and technical considerations of supplemental and substitutional power supply to the constraint conventional power system. To infer the most relevant system approach for PV power plants several solar resources available for PV systems are compared. By combining the different solar resources and respective economics, two major PV systems are identified to be very competitive in almost all regions in the world. The experience curve concept is used as a key technique for the development of scenario assumptions on economic projections for the decade of the 2010s. Main drivers for cost reductions in PV systems are learning and production growth rate, thus several relevant aspects are discussed such as research and development investments, technical PV market potential, different PV technologies and the energetic sustainability of PV. Three major market segments for PV systems are identified: off-grid PV solutions, decentralised small scale on-grid PV systems (several kWp) and large scale PV power plants (tens of MWp). Mainly by application of 'grid-parity' and 'fuel-parity' concepts per country, local market and conventional power plant basis, the global economic market potential for all major PV system segments is derived. PV power plant hybridization potential of all relevant power technologies and the global power plant structure are analyzed regarding technical, economical and geographical feasibility. Key success criteria for hybrid PV power plants are discussed and comprehensively analysed for all adequate power plant technologies, i.e. oil, gas and coal fired power

  20. Economics of hybrid photovoltaic power plants

    Energy Technology Data Exchange (ETDEWEB)

    Breyer, Christian

    2012-08-16

    The global power supply stability is faced to several severe and fundamental threats, in particular steadily increasing power demand, diminishing and degrading fossil and nuclear energy resources, very harmful greenhouse gas emissions, significant energy injustice and a structurally misbalanced ecological footprint. Photovoltaic (PV) power systems are analysed in various aspects focusing on economic and technical considerations of supplemental and substitutional power supply to the constraint conventional power system. To infer the most relevant system approach for PV power plants several solar resources available for PV systems are compared. By combining the different solar resources and respective economics, two major PV systems are identified to be very competitive in almost all regions in the world. The experience curve concept is used as a key technique for the development of scenario assumptions on economic projections for the decade of the 2010s. Main drivers for cost reductions in PV systems are learning and production growth rate, thus several relevant aspects are discussed such as research and development investments, technical PV market potential, different PV technologies and the energetic sustainability of PV. Three major market segments for PV systems are identified: off-grid PV solutions, decentralised small scale on-grid PV systems (several kWp) and large scale PV power plants (tens of MWp). Mainly by application of 'grid-parity' and 'fuel-parity' concepts per country, local market and conventional power plant basis, the global economic market potential for all major PV system segments is derived. PV power plant hybridization potential of all relevant power technologies and the global power plant structure are analyzed regarding technical, economical and geographical feasibility. Key success criteria for hybrid PV power plants are discussed and comprehensively analysed for all adequate power plant technologies, i.e. oil, gas and

  1. Subsidence analysis Forsmark nuclear power plant - unit 1

    International Nuclear Information System (INIS)

    Bono, Nancy; Fredriksson, Anders; Maersk Hansen, Lars

    2010-12-01

    On behalf of SKB, Golder Associates Ltd carried out a risk analysis of subsidence during Forsmark nuclear power plant in the construction of the final repository for spent nuclear fuel near and below existing reactors. Specifically, the effect of horizontal cracks have been studied

  2. Plant life management optimized utilization of existing nuclear power plants

    International Nuclear Information System (INIS)

    Watzinger, H.; Erve, M.

    1999-01-01

    For safe, reliable and economical nuclear power generation it is of central importance to understand, analyze and manage aging-related phenomena and to apply this information in the systematic utilization and as-necessary extension of the service life of components and systems. An operator's overall approach to aging and plant life management which also improves performance characteristics can help to optimize plant operating economy. In view of the deregulation of the power generation industry with its increased competition, nuclear power plants must today also increasingly provide for or maintain a high level of plant availability and low power generating costs. This is a difficult challenge even for the newest, most modern plants, and as plants age they can only remain competitive if a plant operator adopts a strategic approach which takes into account the various aging-related effects on a plant-wide basis. The significance of aging and plant life management for nuclear power plants becomes apparent when looking at their age: By the year 2000 roughly fifty of the world's 434 commercial nuclear power plants will have been in operation for thirty years or more. According to the International Atomic Energy Agency, as many as 110 plants will have reached the thirty-year service mark by the year 2005. In many countries human society does not push the construction of new nuclear power plants and presumably will not change mind within the next ten years. New construction licenses cannot be expected so that for economical and ecological reasons existing plants have to be operated unchallengeably. On the other hand the deregulation of the power production market is asking just now for analysis of plant life time to operate the plants at a high technical and economical level until new nuclear power plants can be licensed and constructed. (author)

  3. Nuclear power plant reliability database management

    International Nuclear Information System (INIS)

    Meslin, Th.; Aufort, P.

    1996-04-01

    In the framework of the development of a probabilistic safety project on site (notion of living PSA), Saint Laurent des Eaux NPP implements a specific EDF reliability database. The main goals of this project at Saint Laurent des Eaux are: to expand risk analysis and to constitute an effective local basis of thinking about operating safety by requiring the participation of all departments of a power plant: analysis of all potential operating transients, unavailability consequences... that means to go further than a simple culture of applying operating rules; to involve nuclear power plant operators in experience feedback and its analysis, especially by following up behaviour of components and of safety functions; to allow plant safety managers to outline their decisions facing safety authorities for notwithstanding, preventive maintenance programme, operating incident evaluation. To hit these goals requires feedback data, tools, techniques and development of skills. The first step is to obtain specific reliability data on the site. Raw data come from plant maintenance management system which processes all maintenance activities and keeps in memory all the records of component failures and maintenance activities. Plant specific reliability data are estimated with a Bayesian model which combines these validated raw data with corporate generic data. This approach allow to provide reliability data for main components modelled in PSA, to check the consistency of the maintenance program (RCM), to verify hypothesis made at the design about component reliability. A number of studies, related to components reliability as well as decision making process of specific incident risk evaluation have been carried out. This paper provides also an overview of the process management set up on site from raw database to specific reliability database in compliance with established corporate objectives. (authors). 4 figs

  4. Nuclear power plant reliability database management

    Energy Technology Data Exchange (ETDEWEB)

    Meslin, Th [Electricite de France (EDF), 41 - Saint-Laurent-des-Eaux (France); Aufort, P

    1996-04-01

    In the framework of the development of a probabilistic safety project on site (notion of living PSA), Saint Laurent des Eaux NPP implements a specific EDF reliability database. The main goals of this project at Saint Laurent des Eaux are: to expand risk analysis and to constitute an effective local basis of thinking about operating safety by requiring the participation of all departments of a power plant: analysis of all potential operating transients, unavailability consequences... that means to go further than a simple culture of applying operating rules; to involve nuclear power plant operators in experience feedback and its analysis, especially by following up behaviour of components and of safety functions; to allow plant safety managers to outline their decisions facing safety authorities for notwithstanding, preventive maintenance programme, operating incident evaluation. To hit these goals requires feedback data, tools, techniques and development of skills. The first step is to obtain specific reliability data on the site. Raw data come from plant maintenance management system which processes all maintenance activities and keeps in memory all the records of component failures and maintenance activities. Plant specific reliability data are estimated with a Bayesian model which combines these validated raw data with corporate generic data. This approach allow to provide reliability data for main components modelled in PSA, to check the consistency of the maintenance program (RCM), to verify hypothesis made at the design about component reliability. A number of studies, related to components reliability as well as decision making process of specific incident risk evaluation have been carried out. This paper provides also an overview of the process management set up on site from raw database to specific reliability database in compliance with established corporate objectives. (authors). 4 figs.

  5. CO2 Price Impacts on Nuclear Power Plant Competitiveness in Croatia

    International Nuclear Information System (INIS)

    Tomsic, Z.; Pasicko, R.

    2010-01-01

    Long term power system planning faces growing number of concerns and uncertainties, which is especially true for nuclear power plants due to their high investment costs and financial risk. In order to analyze competitiveness of nuclear power plants and optimize energy mix, existing models are not sufficient anymore and planners need to think differently in order to face these challenges. Croatia will join EU ETS (European Emission Trading Scheme) with accession to EU (probably in 2012). Thus, for Croatian electrical system it is very important to analyze possible impacts of CO 2 emissions. Analysis presented in this paper is done by electricity market simulation model PLEXOS which was used for modelling Croatian electrical system during development of the Croatian Energy Strategy in 2008. Paper analyzes impacts of CO 2 price on competitiveness of nuclear power plant within Croatian power system between 2020 and 2025. Analyzes are focused on how nuclear power plant influences total emission from the power system regarding coal and gas prices, average electricity price regarding CO 2 , coal and gas prices price. Results of this paper are showing that with emissions from Energy strategy development scenario with two new coal power plants (600 MW each) and two new gas power plants (400 MW each) until 2020, Croatia does not meet Kyoto target due to this emissions from power system. On the other side, introduction of nuclear power plants presented in this paper (1000 MW instead of one coal and one gas power plant) means nearly 6.5 Mt CO 2 emissions less annually and gives possibility to achieve Kyoto target (as this reduced amount represents nearly 22 % of Croatian Kyoto target). Results are also showing how increase in CO 2 price is enhancing competitiveness of a nuclear power plant.(author).

  6. Large and small baseload power plants: Drivers to define the optimal portfolios

    International Nuclear Information System (INIS)

    Locatelli, Giorgio; Mancini, Mauro

    2011-01-01

    Despite the growing interest in Small Medium sized Power Plants (SMPP) international literature provides only studies related to portfolios of large plants in infinite markets/grids with no particular attention given to base load SMPP. This paper aims to fill this gap, investigating the attractiveness of SMPP portfolios respect to large power plant portfolios. The analysis includes nuclear, coal and combined cycle gas turbines (CCGT) of different plant sizes. The Mean Variance Portfolio theory (MVP) is used to define the best portfolio according to Internal Rate of Return (IRR) and Levelised Unit Electricity Cost (LUEC) considering the life cycle costs of each power plant, Carbon Tax, Electricity Price and grid dimension. The results show how large plants are the best option for large grids, while SMPP are as competitive as large plants in small grids. In fact, in order to achieve the highest profitability with the lowest risk it is necessary to build several types of different plants and, in case of small grids, this is possible only with SMPP. A further result is the application of the framework to European OECD countries and the United States assessing their portfolios. - Highlights: ► The literature about power plant portfolios does not consider small grids and IRR. ► We evaluated Base load portfolios respect to IRR and LUEC. ► We assessed the influence of grid and plant size, CO 2 cost and Electricity Price. ► Large plants are optimal for large markets even if small plants have similar IRR. ► Small plants are suitable to diversify portfolios in small grids reducing the risk.

  7. Some power uprate issues in nuclear power plants

    International Nuclear Information System (INIS)

    Tipping, Philip

    2008-01-01

    Issues and themes concerned with nuclear power plant uprating are examined. Attention is brought to the fact that many candidate nuclear power plants for uprating have anyway been operated below their rated power for a significant part of their operating life. The key issues remain safety and reliability in operation at all times, irrespective of the nuclear power plant's chronological or design age or power rating. The effects of power uprates are discussed in terms of material aspects and expected demands on the systems, structures and components. The impact on operation and maintenance methods is indicated in terms of changes to the ageing surveillance programmes. Attention is brought to the necessity checking or revising operator actions after power up-rating has been implemented

  8. Auxiliary feedwater system risk-based inspection guide for the Palo Verde Nuclear Power Plant

    International Nuclear Information System (INIS)

    Bumgardner, J.D.; Moffitt, N.E.; Gore, B.F.; Vo, T.V.; Sloan, J.A.

    1993-02-01

    In a study sponsored by the US Nuclear Regulatory Commission (NRC), Pacific Northwest Laboratory has developed and applied a methodology for deriving plant-specific risk-based inspection guidance for the auxiliary feedwater (AFW) system at pressurized water reactors that have not undergone probabilistic risk assessment (PRA). This methodology uses existing PRA results and plant operating experience information. Existing PRA-based inspection guidance information recently developed for the NRC for various plants was used to identify generic component failure modes. This information was then combined with plant-specific and industry-wide component information and failure data to identify failure modes and failure mechanisms for the AFW system at the selected plants. Palo Verde was selected as one of a series of plants for study. The product of this effort is a prioritized listing of AFW failures which have occurred at the plant and at other PWRs. This listing is intended for use by NRC inspectors in the preparation of inspection plans addressing AFW risk-important components at the Palo Verde plants

  9. Auxiliary feedwater system risk-based inspection guide for the McGuire nuclear power plant

    International Nuclear Information System (INIS)

    Bumgardner, J.D.; Lloyd, R.C.; Moffitt, N.E.; Gore, B.F.; Vo, T.V.

    1994-05-01

    In a study sponsored by the US Nuclear Regulatory Commission (NRC), Pacific Northwest Laboratory has developed and applied a methodology for deriving plant-specific risk-based inspection guidance for the auxiliary feedwater (AFW) system at pressurized water reactors that have not undergone probabilistic risk assessment (PRA). This methodology uses existing PRA results and plant operating experience information. Existing PRA-based inspection guidance information recently developed for the NRC for various plants was used to identify generic component failure modes. This information was then combined with plant-specific and industry-wide component information and failure data to identify failure modes and failure mechanisms for the AFW system at the selected plants. McGuire was selected as one of a series of plants for study. The product of this effort is a prioritized listing of AFW failures which have occurred at the plant and at other PWRs. This listing is intended for use by NRC inspectors in the preparation of inspection plans addressing AFW risk-important components at the McGuire plant

  10. Auxiliary feedwater system risk-based inspection guide for the Maine Yankee Nuclear Power Plant

    International Nuclear Information System (INIS)

    Gore, B.F.; Vo, T.V.; Moffitt, N.E.; Bumgardner, J.D.

    1992-10-01

    In a study sponsored by the US Nuclear Regulatory Commission (NRC), Pacific Northwest Laboratory has developed and applied a methodology for deriving plant-specific risk-based inspection guidance for the auxiliary feedwater (AFW) system at pressurized water reactors that have not undergone probabilistic risk assessment (PRA). This methodology uses existing PRA results and plant operating experience information. Existing PRA-based inspection guidance information recently developed for the NRC for various plants was used to identify generic component failure modes. The information was then combined with plant-specific and industry-wide component information and failure data to identify failure modes and failure mechanisms for the AFW system at the selected plants. Maine Yankee was selected as one of a series of plants for study. ne product of this effort is a prioritized listing of AFW failures which have occurred at the plant and at other PWRs. This listing is intended for use by NRC inspectors in the preparation of inspection plans addressing AFW risk-important components at the Maine Yankee plant

  11. Auxiliary feedwater system risk-based inspection guide for the Point Beach nuclear power plant

    International Nuclear Information System (INIS)

    Lloyd, R.C.; Moffitt, N.E.; Gore, B.F.; Vo, T.V.; Vehec, T.A.

    1993-02-01

    In a study sponsored by the US Nuclear Regulatory Commission (NRC), Pacific Northwest Laboratory has developed and applied a methodology for deriving plant-specific risk-based inspection guidance for the auxiliary feedwater (AFW) system at pressurized water reactors that have not undergone probabilistic risk assessment (PRA). This methodology uses existing PRA results and plant operating experience information. Existing PRA-based inspection guidance information recently developed for the NRC for various plants was used to identify generic component failure modes. This information was then combined with plant-specific and industry-wide component information and failure data to identify failure modes and failure mechanisms for the AFW system at the selected plants. Point Beach was selected as one of a series of plants for study. The product of this effort is a prioritized listing of AFW failures which have occurred at the plant and at other PWRS. This listing is intended for use by NRC inspectors in the preparation of inspection plans addressing AFW risk-important components at the Point Beach plant

  12. A common high standard for nuclear power plant exports: overview and analysis of the Nuclear Power Plant Exporters' Principles of Conduct

    International Nuclear Information System (INIS)

    Perkovich, George; Radzinsky, Brian

    2012-01-01

    At this time, there is no overarching global framework to regulate the development of the nuclear power industry. Laws concerning the export of nuclear technology vary across jurisdictions, and politically-binding arrangements such as the Nuclear Suppliers Group (NSG) help ensure that weapons-usable or dual-use technologies are not exported, but no single international regime or agreement manages the gamut of potential risks that may arise from the export of civilian nuclear power plants. Accordingly in 2008, the Carnegie Endowment for International Peace convened internationally-recognised experts in nuclear energy to begin a dialogue with nuclear power plant vendors about defining common criteria for the socially responsible export of nuclear power plants. The goal was to articulate a comprehensive set of principles and best practices that would raise the overall standard of practice for exports of nuclear power plants while enjoying widespread support and adherence. The outcome of this process is the Nuclear Power Plant Exporters' Principles of Conduct - an export-oriented code of conduct for nuclear power plant vendors. The Principles of Conduct help ensure that the participating companies will proceed with the sale of a new nuclear power plant only after a careful assessment of the legal, political, and technical contexts surrounding potential customers. It comprises six 'principles' that each address a major area of concern involved in the export of a nuclear power plant: safety, physical security, environmental protection and spent fuel management, systems of compensation for nuclear damage, non-proliferation and safeguards, and business ethics. The Principles of Conduct entail vendor responsibilities to apply specific standards or engage in certain practices before signing contracts and during the marketing and construction phases of a nuclear power plant export project. Conformity with the Principles of Conduct is voluntary and not-legally binding, but the

  13. Offshore atomic power plants

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Various merits of offshore atomic power plants are illustrated, and their systems are assessed. The planning of the offshore atomic power plants in USA is reviewed, and the construction costs of the offshore plant in Japan were estimated. Air pollution problem may be solved by the offshore atomic power plants remarkably. Deep water at low temperature may be advantageously used as cooling water for condensers. Marine resources may be bred by building artificial habitats and by providing spring-up equipments. In the case of floating plants, the plant design can be standardized so that the construction costs may be reduced. The offshore plants can be classified into three systems, namely artificial island system, floating system and sea bottom-based system. The island system may be realized with the present level of civil engineering, but requires the development of technology for the resistance of base against earthquake and its calculation means. The floating system may be constructed with conventional power plant engineering and shipbuilding engineering, but the aseismatic stability of breakwater may be a problem to be solved. Deep water floating system and deep water submerging system are conceivable, but its realization may be difficult. The sea bottom-based system with large caissons can be realized by the present civil engineering, but the construction of the caissons, stability against earthquake and resistance to waves may be problems to be solved. The technical prediction and assessment of new plant sites for nuclear power plants have been reported by Science and Technology Agency in 1974. The construction costs of an offshore plant has been estimated by the Ministry of International Trade and Industry to be yen71,026/kW as of 1985. (Iwakiri, K.)

  14. A Comparison Study on the Integrated Risk Estimation for Various Power Systems

    International Nuclear Information System (INIS)

    Kim, Tae Woon; Ha, J. J.; Kim, S. H.; Jeong, J. T.; Min, K. R.; Kim, K. Y.

    2007-06-01

    The objective of this study is to establish a system for the comparative analysis of the environmental impacts, risks, health effects, and social acceptance for various electricity generation systems and a computational framework and necessary databases. In this study, the second phase of the nuclear research and development program(2002-2004), the methodologies for the comparative analysis of the environmental impacts, risks, and health effects for various electricity generation systems was investigated and applied to reference power plants. The life cycle assessment (LCA) methodology as a comparative analysis tool for the environmental impacts was adopted and applied to fossil-fueled and nuclear power plants. The scope of the analysis considered in this study are the construction, operation/fuel cycle), and demolition of each power generation system. In the risk analysis part, the empirical and analytical methods were adopted and applied to fossil-fueled and nuclear power plants. In the empirical risk assessment part, we collected historical experiences of worldwide energy-related accidents with fatalities over the last 30 years. The scope of the analysis considered in this study are the construction, operation (fuel cycle), and demolition stages of each power generation systems. The risks for the case of nuclear power plants which have potential releases of radioactive materials were estimated In a probabilistic way (PSA) by considering the occurrence of severe accidents and compared with the risks of other electricity generation systems. The health effects testimated as external cost) resulting from the operation of nuclear, coal, and hydro power systems were estimated and compared by using the program developed by the IAEA. Regarding a comprehensive comparison of the various power systems, the analytic hierarchy process (AHP) method is introduced to aggregate the diverse information under conflicting decision criteria. Social aspect is treated by a web

  15. A primer on the Bataan Nuclear Power Plant

    International Nuclear Information System (INIS)

    Gonzales, S.R.

    This article explains in simple terms about nuclear energy, nuclear research and power reactor and its operations. It gives the historical background of the presently being constructed Philippine Nuclear Power Plant (PNPP-I) at Napot Point, Bataan. Because of rising opposition to its construction aggravated by the TMI accident, the author tries to explain and convince those against nuclear power that the reactor will be safe within reasonable risk as deduced from testimonies of experts involved in the construction and later in its operation. (author)

  16. Nuclear Plant Modification in a Risk-Informed Environment

    International Nuclear Information System (INIS)

    Gallucci, Raymond H.V.

    2002-01-01

    This paper examines a specific nuclear power plant modification performed in a risk-informed regulatory environment. It quantifies both the permanent and temporary effects of the modification, and performs a cost-benefit evaluation. (authors)

  17. Selection of sites for nuclear power plants in The Netherlands. Pt. C

    International Nuclear Information System (INIS)

    1986-01-01

    This advice is concerned with the question where possible new nuclear power plants can at best be sited in the Netherlands. Safety risks of power plants are considered (sourceterm analysis, meteorologic aspects). A site analysis is presented on the base of criteria like population density, possible emergency provisions, contamination of agricultural areas etc. Reports of several committees are included. (Auth.)

  18. Main results of the German nuclear power plant risk study

    International Nuclear Information System (INIS)

    Danzmann, H.J.

    1981-01-01

    The subject is discussed under the headings: introduction; purpose and task of the German risk study; approach; results of investigations (analyses of engineered plant features; determination of accident consequences); emergency response model; protective actions and countermeasures; evaluation. (U.K.)

  19. Purchasing and supply quality management in a power plant : a case study

    OpenAIRE

    2012-01-01

    M. Ing. This research study aims at presenting the management of quality problem issues that often result from procured items in a power plant. The motivation for carrying out this research was an unacceptable risk of undesirable impact on plant availability, or operating costs that arises from quality problem issues of procured items in a particular power plant. In this dissertation, the author aims to provide an overview of quality management and procurement management, by focusing on ho...

  20. Hybrid combined cycle power plant

    International Nuclear Information System (INIS)

    Veszely, K.

    2002-01-01

    In case of re-powering the existing pressurised water nuclear power plants by the proposed HCCPP solution, we can increase the electricity output and efficiency significantly. If we convert a traditional nuclear power plant unit to a HCCPP solution, we can achieve a 3.2-5.5 times increase in electricity output and the achievable gross efficiency falls between 46.8-52% and above, depending on the applied solution. These figures emphasise that we should rethink our power plant technologies and we have to explore a great variety of HCCPP solutions. This may give a new direction in the development of nuclear reactors and power plants as well.(author)

  1. Nuclear Liability and Insurance Cover for Risk of Nuclear Power Plants - Situation for Nuclear Installations in Germany

    International Nuclear Information System (INIS)

    Boediker, T.

    1998-01-01

    A dispute about nuclear liability and insurance cover for risks of nuclear power plants from an insurer's point of view has to determine and to judge the essential risk relevant factors. These are beside plant and site specific factors considerations of insurance restrictions in the extent of cover compared with the legal scope of liability for (re-)insurability's sake. Among such consideration are: financial limitation and obligation for its reinstatement, exclusions for gradual emissions of approved activities, armed conflicts, hostilities, civil war, insurrections or grave natural disaster and restrictions in the limitation and preclusion periods. In comparison with conventional liability risks there are some specialties to be considered some of which prove to be a risk relief other as a risk burden for insurance: Salvage expenses or interests and court costs to be paid by unsuccessful party in a lost litigation do not fall under legal liability and hence are excluded from the financial security cover so that are compensation is subject to agreed separate limits. A serious burden for the insurers can result out of the loss regulation costs in case of a severe nuclear accident. These expenses, which can exceed hundred million DM by far, are to be carried by the insurers in the frame of their obligation to investigate raised claims. Therefore the insurers should aim a fixed limitation in order to restrict their limit. (author)

  2. Elecnuc. Nuclear power plants in the world

    International Nuclear Information System (INIS)

    2003-01-01

    This 2003 version of Elecnuc contents information, data and charts on the nuclear power plants in the world and general information on the national perspectives concerning the electric power industry. The following topics are presented: 2002 highlights; characteristics of main reactor types and on order; map of the French nuclear power plants; the worldwide status of nuclear power plants on 2002/12/3; units distributed by countries; nuclear power plants connected to the Grid by reactor type groups; nuclear power plants under construction; capacity of the nuclear power plants on the grid; first electric generations supplied by a nuclear unit; electrical generation from nuclear plants by country at the end 2002; performance indicator of french PWR units; trends of the generation indicator worldwide from 1960 to 2002; 2002 cumulative Load Factor by owners; nuclear power plants connected to the grid by countries; status of license renewal applications in Usa; nuclear power plants under construction; Shutdown nuclear power plants; exported nuclear power plants by type; exported nuclear power plants by countries; nuclear power plants under construction or order; steam generator replacements; recycling of Plutonium in LWR; projects of MOX fuel use in reactors; electricity needs of Germany, Belgium, Spain, Finland, United Kingdom; electricity indicators of the five countries. (A.L.B.)

  3. The economics of new nuclear power plants in liberalized electricity markets

    International Nuclear Information System (INIS)

    Linares, Pedro; Conchado, Adela

    2013-01-01

    Even after Fukushima, the nuclear debate is strong in many countries, with the discussion of its economics being a significant part of it. However, most of the estimates are based on a levelized-cost methodology, which presents several shortcomings, particularly when applied to liberalized electricity markets. Our paper provides results based on a different methodology, by which we determine the break-even investment cost for nuclear power plants to be competitive with other electricity generation technologies. Our results show that the cost competitiveness of nuclear power plants is questionable, and that public support of some sort would be needed if new nuclear power plants are to be built in liberalized markets. - Highlights: • We propose an alternative more realistic than LEC for the evaluation of the economics of nuclear electricity. • Our results show that the cost competitiveness of nuclear power plants is questionable. • Building nuclear power plants will require public support, particularly regarding risk management. • These results are less optimistic than previous, LEC-based, estimates

  4. The autumn when 27 gas power plants disappeared

    International Nuclear Information System (INIS)

    Braaten, Jan

    2003-01-01

    In the autumn of 2002 the influx of water to the hydropower plants in the Nordic countries was only half the normal value. The probability of such an extreme failure is less than 0.5 per cent. Prices rose during the autumn, which led to import to the hydropower system and start-up of stand by production capacity and consumption cut. The market and trade essentially worked well and the high prices were the prime mover. Hydropower is an unstable resource and one therefore needs trade possibilities and flexibility in consumption and production to handle variation of the influx. Also, perhaps, one should stimulate the reservoir owners to retain some more water in the reservoirs. A weak energy balance increases the risk of dry year crises. An active grip on this is necessary to reduce vulnerability in the future. While there was plenty of water in the first part of 2002, the influx to the power plants failed fatally during autumn; from week number 31 to the rest of the year only the equivalent of 35 TWh, which is half that of a normal year. This is a historic all-time low. Early next year the influx of water was less than normal. The energy shortage due to hydropower failure during the last 20 weeks of 2002 was greater than it would have been if instead all the Swedish nuclear power had failed. If an energy failure this size should have been covered by means of gas power, 24 gas power works of 400 MW each would be required. At the same time, the import from the Continent was restricted by problems with two cables corresponding to a loss of tree more gas power plants. Thus, the power crisis of the autumn of 2002 corresponds to 27 gas power plants. Gas power plants is a controversial issue in the energy policy debate in Norway, but there are plans for a 400 MW plant. This is food for thought for all those politicians who are worried about the possible environmental impact of gas power plants.

  5. Environmental impact assessment of coal power plants in operation

    Directory of Open Access Journals (Sweden)

    Bartan Ayfer

    2017-01-01

    Full Text Available Coal power plants constitute an important component of the energy mix in many countries. However, coal power plants can cause several environmental risks such as: climate change and biodiversity loss. In this study, a tool has been proposed to calculate the environmental impact of a coal-fired thermal power plant in operation by using multi-criteria scoring and fuzzy logic method. We take into account the following environmental parameters in our tool: CO, SO2, NOx, particulate matter, fly ash, bottom ash, the cooling water intake impact on aquatic biota, and the thermal pollution. In the proposed tool, the boundaries of the fuzzy logic membership functions were established taking into account the threshold values of the environmental parameters which were defined in the environmental legislation. Scoring of these environmental parameters were done with the statistical analysis of the environmental monitoring data of the power plant and by using the documented evidences that were obtained during the site visits. The proposed method estimates each environmental impact factor level separately and then aggregates them by calculating the Environmental Impact Score (EIS. The proposed method uses environmental monitoring data and documented evidence instead of using simulation models. The proposed method has been applied to the 4 coal-fired power plants that have been operation in Turkey. The Environmental Impact Score was obtained for each power plant and their environmental performances were compared. It is expected that those environmental impact assessments will contribute to the decision-making process for environmental investments to those plants. The main advantage of the proposed method is its flexibility and ease of use.

  6. Environmental impact assessment of coal power plants in operation

    Science.gov (United States)

    Bartan, Ayfer; Kucukali, Serhat; Ar, Irfan

    2017-11-01

    Coal power plants constitute an important component of the energy mix in many countries. However, coal power plants can cause several environmental risks such as: climate change and biodiversity loss. In this study, a tool has been proposed to calculate the environmental impact of a coal-fired thermal power plant in operation by using multi-criteria scoring and fuzzy logic method. We take into account the following environmental parameters in our tool: CO, SO2, NOx, particulate matter, fly ash, bottom ash, the cooling water intake impact on aquatic biota, and the thermal pollution. In the proposed tool, the boundaries of the fuzzy logic membership functions were established taking into account the threshold values of the environmental parameters which were defined in the environmental legislation. Scoring of these environmental parameters were done with the statistical analysis of the environmental monitoring data of the power plant and by using the documented evidences that were obtained during the site visits. The proposed method estimates each environmental impact factor level separately and then aggregates them by calculating the Environmental Impact Score (EIS). The proposed method uses environmental monitoring data and documented evidence instead of using simulation models. The proposed method has been applied to the 4 coal-fired power plants that have been operation in Turkey. The Environmental Impact Score was obtained for each power plant and their environmental performances were compared. It is expected that those environmental impact assessments will contribute to the decision-making process for environmental investments to those plants. The main advantage of the proposed method is its flexibility and ease of use.

  7. Hazards from radioactivity of fly ash of Greek coal power plants (CPP)

    International Nuclear Information System (INIS)

    Papastefanou, C.; Charalambous, S.

    1980-01-01

    Fly ash and fine dispersion releases from coal combustion in Greek coal power plants were studied. Concentrations in the fly ash up to 20 pCi/g and 10 pCi/g were measured for 238 U and 226 Ra respectively (not in secular equilibrium). Risk from the fly ash derives from its escape in particulate form or fine dispersion and from its use as a substitute for cement in concrete. The new data indicate that coal power plants discharge relatively larger quantities of radioactive material into the atmosphere than nuclear power plants of comparable size, during normal operation. (H.K.)

  8. Power generation by nuclear power plants

    International Nuclear Information System (INIS)

    Bacher, P.

    2004-01-01

    Nuclear power plays an important role in the world, European (33%) and French (75%) power generation. This article aims at presenting in a synthetic way the main reactor types with their respective advantages with respect to the objectives foreseen (power generation, resources valorization, waste management). It makes a fast review of 50 years of nuclear development, thanks to which the nuclear industry has become one of the safest and less environmentally harmful industry which allows to produce low cost electricity: 1 - simplified description of a nuclear power generation plant: nuclear reactor, heat transfer system, power generation system, interface with the power distribution grid; 2 - first historical developments of nuclear power; 3 - industrial development and experience feedback (1965-1995): water reactors (PWR, BWR, Candu), RBMK, fast neutron reactors, high temperature demonstration reactors, costs of industrial reactors; 4 - service life of nuclear power plants and replacement: technical, regulatory and economical lifetime, problems linked with the replacement; 5 - conclusion. (J.S.)

  9. Nuclear Power Plants in the World

    International Nuclear Information System (INIS)

    2000-01-01

    The Japan Atomic Industrial Forum (JAIF) used every year to summarize a trend survey on the private nuclear power plants in the world in a shape of the 'Developmental trends on nuclear power plants in the world'. In this report, some data at the end of 1999 was made up on bases of answers on questionnaires from 72 electric companies in 31 nations and regions in the world by JAIF. This report is comprised of 19 items, and contains generating capacity of the plants; current status of Japan; trends of generating capacity of operating the plants, the plant orders and generating capacity of the plants; world nuclear capacity by reactor type; location of the plants; the plants in the world; and so forth. And, it also has some survey results on the 'Liberalization of electric power markets and nuclear power generation' such as some 70% of respondents in nuclear power for future option, gas-thermal power seen as power source with most to gain from liberalization, merits on nuclear power generation (environmental considerations and supply stability), most commonly voiced concern about new plant orders in poor economy, and so forth. (G.K.)

  10. Nuclear power plants - a solution for the future

    International Nuclear Information System (INIS)

    Sinn, D.

    1978-01-01

    This book is not written for experts, but for interested laymen. The arguments in favour of nuclear power plants are presented in an intelligible and critical manner. The problem of nuclear power is reviewed at a moment where the nuclear controversy has even led to lawsuits. Still, there is hope for a secure energy supply - and fear of the risks that the future might bring and which may even endanger our lives. (GL) [de

  11. Expert report of ENSI on the request of EKKB AG for a general license - Project 'New nuclear power plant to replace the Beznau plant'

    International Nuclear Information System (INIS)

    2010-09-01

    The 'Ersatz Kernkraftwerk Beznau AG' (EKKB) Company submitted to the Swiss Federal Inspectorate of Nuclear Safety (ENSI) a request for a general license for a new power plant to be built near to the Beznau power plants. According to the law, all damage risks with a probability higher than 10 -4 /a must be taken into account through protection measures. The considered risks concern the power plant itself as well as the population in the neighbourhood and the environment. The purpose of the general license is to demonstrate that the site chosen for the foreseen power plant is acceptable and that the risks can be counteracted through adequate measures. The buildings of the power plant and their partition on the Beznau Island in the Aare River are briefly described. The reactor is a Light Water Reactor of third generation with a maximum electrical power of 1450 MW el ±20%. The main cooling is provided by a hybrid system of water evaporation and air heating, what reduces the plume at the exit of the cooling tower. First, it is demonstrated that, in the case of a very unlikely severe accident in the power plant, the people in the neighbourhood can be evacuated quickly. Then, numerous types of possible accidents in the neighbourhood of the power plant are analyzed in order to settle their possible negative influence on the operation of the power plant: bursting of gas containers on the neighbouring roads and railways, fires of all types of hydrocarbons, air pollution through chloride gas, etc. The check by ENSI of the EKKB studies on the potential danger for the power plant through neighbouring industrial plants, roads or railways demonstrated that none of the considered accidents presents an unacceptable risk for the power plant: on the one hand, these plants are located too far from the power plant, so that a sensible injury to the power plant safety can be excluded; on the other, the protection of the power plant can be guaranteed through appropriate technical

  12. New risks for a new era in nuclear power development

    International Nuclear Information System (INIS)

    Purica, I.

    2002-01-01

    At present, the nuclear power is re-emerging after a still ongoing controversial period. The risks, that have started to be analyzed in the nuclear industry, opened the way for methods and algorithms that are wide spread now in all situations whose strong dynamics requires that kind of approach. The onset of terrorism in the last year and risk exposure of the nuclear power plants, that are potential sources of hazards if targeted appropriately, require orienting the risk methods to this type of analysis along with the technical solutions. Also, the financial volatility of the world of today, creates barriers in the development of nuclear plant financial structures. The possibility to combine the decommissioning of old thermal capacities and their replacement with nuclear capacities that results in Emission Reduction Units that can be traded internationally, raise the opportunity for a better financial structure of nuclear power projects in connection with thermal capacity shutdown. The risk decreasing is significant and the impact on the costs make nuclear power even more cost-effective. In the paper we review some aspects of terrorism risk analysis and the impact of emission trading on the financial structure of an NPP project in very conservative conditions. (author)

  13. A study on the assessment of safety culture impacts on risk of nuclear power plants using common uncertainty source model

    International Nuclear Information System (INIS)

    Lee, Yong Suk; Bang, Young Suk; Chung, Chang Hyun; Jeong, Ji Hwan

    2004-01-01

    Since International Safety Advisory Group (INSAG) introduced term 'safety culture', it has been widely recognized that safety culture has an important role in safety of nuclear power plants. Research on the safety culture can be divided in the following two parts. 1) Assessment of safety culture (by interview, questionnaire, etc.) 2) Assessment of link between safety culture and safety of nuclear power plants. There is a substantial body of literature that addresses the first part, but there is much less work that addresses the second part. To address the second part, most work focused on the development of model incorporating safety culture into Probabilistic Safety Assessment (PSA). One of the most advanced methodology in the area of incorporating safety culture quantitatively into PSA is System Dynamics (SD) model developed by Kwak et al. It can show interactions among various factors which affect employees' productivity and job quality. Also various situations in nuclear power plant can be simulated and time-dependent risk can be recalculated with this model. But this model does not consider minimal cut set (MCS) dependency and uncertainty of risk. Another well-known methodology is Work Process Analysis Model (WPAM) developed by Davoudian. It considers MCS dependency by modifying conditional probability values using SLI methodology. But we found that the modified conditional probability values in WPAM are somewhat artificial and have no sound basis. WPAM tend to overestimate conditional probability of hardware failure, because it uses SLI methodology which is normally used in Human Reliability Analysis (HRA). WPAM also does not consider uncertainty of risk. In this study, we proposed methodology to incorporate safety culture into PSA quantitatively that can deal with MCS dependency and uncertainty of risk by applying the Common Uncertainty Source (CUS) model developed by Zhang. CUS is uncertainty source that is common to basic events, and this can be physical

  14. Tactical supply chain planning for a forest biomass power plant under supply uncertainty

    International Nuclear Information System (INIS)

    Shabani, Nazanin; Sowlati, Taraneh; Ouhimmou, Mustapha; Rönnqvist, Mikael

    2014-01-01

    Uncertainty in biomass supply is a critical issue that needs to be considered in the production planning of bioenergy plants. Incorporating uncertainty in supply chain planning models provides improved and stable solutions. In this paper, we first reformulate a previously developed non-linear programming model for optimization of a forest biomass power plant supply chain into a linear programming model. The developed model is a multi-period tactical-level production planning problem and considers the supply and storage of forest biomass as well as the production of electricity. It has a one-year planning horizon with monthly time steps. Next, in order to incorporate uncertainty in monthly available biomass into the planning, we develop a two-stage stochastic programming model. Finally, to balance the risk and profit, we propose a bi-objective model. The results show that uncertainty in availability of biomass has an additional cost of $0.4 million for the power plant. Using the proposed stochastic optimization model could reduce this cost by half. - Highlights: • Developed a two-stage stochastic optimization model to consider supply uncertainty. • Maximized the profit of a forest biomass power plant value chain. • Minimized two risk measures, variability index and downside risk, to manage risks. • Stochastic optimization model provided feasible solution for all scenarios. • Results showed a trade-off between profit and risk management

  15. Perspectives of nuclear power plants

    International Nuclear Information System (INIS)

    Vajda, Gy.

    2001-01-01

    In several countries the construction of nuclear power plants has been stopped, and in some counties several plants have been decommissioned or are planned to. Therefore, the question arises: have nuclear power plants any future? According to the author, the question should be reformulated: can mankind survive without nuclear power? To examine this challenge, the global power demand and its trends are analyzed. According to the results, traditional energy sources cannot be adequate to supply power. Therefore, a reconsideration of nuclear power should be imminent. The economic, environmental attractions are discussed as opposite to the lack of social support. (R.P.)

  16. Problems of power plant capital demands

    International Nuclear Information System (INIS)

    Slechta, V.; Bohal, L.

    1986-01-01

    The problems are discussed of requirements for investment for power plants in Czechoslovakia. Since the construction was finished of coal-burning 110 MW power plants with six power units, specific capital cost has steadily been growing. The growth amounts to 6 to 8% per year while the principle has been observed that specific capital cost decreases with increased unit power. Attention is paid to the cost of the subcontractors of the building and technological parts of a power plant and to the development of productivity of labour. A comparison is tabulated of cost for coal-burning power plants with 100 MW and 200 MW units and for nuclear power plants with WWER-440 reactors. Steps are suggested leading to a reduction of the capital cost of nuclear power plants. It is stated that should not these steps be taken, the envisaged development of nuclear power would be unbearable for the Czechoslovak national economy. (Z.M.). 8 tabs., 3 refs

  17. Application of risk based inspection as a part of life management of nuclear power plants

    International Nuclear Information System (INIS)

    Vinod, Gopika; Babar, A.K.; Saraf, R.K.; Kushwaha, H.S.; Venkat Raj, V.

    2002-01-01

    Full text: Risk Informed approach is a systematic effort to improve plant safety in a more efficient manner by distributing the available safety resources depending on the importance to plant safety. This approach has found immense application in various aspects associated with Nuclear Power Plants, including design, manufacturing, operation and regulation. Typical applications of Risk Informed approach are in Technical Specification, In-Service Inspection (ISI) requirements, Motor Operated Valve testing, Configuration Control etc. In order to cater to such variety of Probabilistic Safety Assessment (PSA) based Risk Informed requirements, a software package, 'Risk Monitor' has been developed by the authors. An important application of Risk informed approach that has been undertaken for Indian Pressurised Heavy Water Reactor (IPHWR) is towards Risk Informed In-Service Inspection (RI-ISI). Studies are being conducted to evolve an inspection plan that is optimised to provide effective inspections at the right location with a proper inspection frequency. Using risk informed approach, the identification of system / component for inspection resource allocation is based on the results from Level 1 PSA of a NPP. Even though this methodology can be employed on any of the nuclear components/systems such as mechanical systems, instrumentation, etc., as a starting point, piping has been considered for employing Risk Informed Inspection. Plant risk assessment is modelled through the analysis of Core Damage Frequency (CDF) using PSA models. Risk Informed Inspection program of piping involves the estimation of failure probability or frequency of a piping segment and estimation of consequences of piping failures. ISI program changes could affect the failure probability values of piping and can introduce a change in CDF. These effects can be brought out through the implementation of Risk Informed inspection strategy. Various importance measures like Fussel-Vesely, Birnbaum

  18. Consideration of early closure or continued operation of a nuclear power plant

    International Nuclear Information System (INIS)

    2006-07-01

    This publication provides information to management and executives of electrical utilities responsible for the operation of nuclear power plants who are tasked with decision making related to early closures or continued operation. This information is based on the experiences of a number of countries in addressing a spectrum of issues broader than only the economics of the operation of the plant itself. Any major decision involving changes in direction for a major investment such as a nuclear power plant has the potential to incur considerable additional costs for stakeholders. Major economic risks can be unexpectedly encountered when decisions based on a simplified economic understanding of energy options are successfully challenged on the grounds that choices and decisions have been made without accounting for some environmental, social or economic issues which are considered of prime significance to important stakeholders. Such risks include not only changes in project scope and delays in project implementation due to re-evaluations necessitated by such challenges, but risks related to the effectiveness, efficiency and safety of ongoing operations or shutdown maintenance of the nuclear power plant. Additional risks encountered at this stage are the adequacy of the decommissioning fund and the need to establish a process whereby the availability of adequate funds will be assured at the time of the final plant shutdown. This publication provides information on several of these additional issues important to key stakeholders, and on methods that allow for their assessment and consideration when developing recommendations related to early closures or continued operations of a NPP. This publication consists of two parts: Part I: Includes a discussion of the main issues for consideration, with emphasis on issues important to stakeholders in addition to plant owners. Part II: Provides an example of a basic analytical approach to the assessment of plant life cycle

  19. Nuclear power plant diagnostic system

    International Nuclear Information System (INIS)

    Prokop, K.; Volavy, J.

    1982-01-01

    Basic information is presented on diagnostic systems used at nuclear power plants with PWR reactors. They include systems used at the Novovoronezh nuclear power plant in the USSR, at the Nord power plant in the GDR, the system developed at the Hungarian VEIKI institute, the system used at the V-1 nuclear power plant at Jaslovske Bohunice in Czechoslovakia and systems of the Rockwell International company used in US nuclear power plants. These diagnostic systems are basically founded on monitoring vibrations and noise, loose parts, pressure pulsations, neutron noise, coolant leaks and acoustic emissions. The Rockwell International system represents a complex unit whose advantage is the on-line evaluation of signals which gives certain instructions for the given situation directly to the operator. The other described systems process signals using similar methods. Digitized signals only serve off-line computer analyses. (Z.M.)

  20. Safety of Nuclear Power Plants: Commissioning and Operation

    International Nuclear Information System (INIS)

    2011-01-01

    This publication is a revision of Safety Requirements No. NS-R-2, Safety of Nuclear Power Plants: Operation, and has been extended to cover the commissioning stage. It describes the requirements to be met to ensure the safe operation of nuclear power plants. Over recent years there have been developments in areas such as long term operation, plant ageing, periodic safety review, probabilistic safety analysis and risk informed decision making processes. It became necessary to revise the IAEA's safety requirements in these areas and to correct and/or improve the publication on the basis of feedback from its application by both the IAEA and its Member States. In addition, the requirements are governed by, and must apply, the safety objective and safety principles that are established in the Fundamental Safety Principles. Contents: 1. Introduction; 2. Safety objectives and principles; 3. The management and organizational structure of the operating organization; 4. Management of operational safety; 5. Operational safety programmes; 6. Plant commissioning; 7. Plant operations; 8. Maintenance, testing, surveillance and inspection; 9. Preparation for decommissioning.

  1. Safety of Nuclear Power Plants: Commissioning and Operation. Specific Safety Requirements

    International Nuclear Information System (INIS)

    2016-01-01

    This publication describes the requirements to be met to ensure the safe operation of nuclear power plants. It takes into account developments in areas such as long term operation of nuclear power plants, plant ageing, periodic safety review, probabilistic safety analysis and risk informed decision making processes. In addition, the requirements are governed by, and must apply, the safety objective and safety principles that are established in the IAEA Safety Standards Series No. SF-1, Fundamental Safety Principles. A review of Safety Requirements publications was commenced in 2011 following the accident in the Fukushima Daiichi nuclear power plant in Japan. The review revealed no significant areas of weakness and resulted in just a small set of amendments to strengthen the requirements and facilitate their implementation, which are contained in the present publication

  2. Development of the Risk-Based Inspection Techniques and Pilot Plant Activities

    International Nuclear Information System (INIS)

    Phillips, J.H.

    1997-01-01

    Risk-based techniques have been developed for commercial nuclear power plants. System boundaries and success criteria is defined using the probabilistic risk analysis or probabilistic safety analysis developed to meet the individual plant evaluation. Final ranking of components is by a plant expert panel similar to the one developed for maintenance rule. Components are identified as being high risk-significant or low-risk significant. Maintenance and resources are focused on those components that have the highest risk-significance. The techniques have been developed and applied at a number of pilot plants. Results from the first risk-based inspection pilot plant indicates that safety due to pipe failure can be doubled while the inspection reduced to about 80% when compared with current inspection programs. The reduction in inspection reduces the person-rem exposure resulting in further increases in safety. These techniques have been documented in publication by the ASME CRTD

  3. Performance of Generating Plant: Managing the Changes. Part 4: Markets and Risk Management Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Moss, Terry; Loedolff, Gerhard; Griffin, Rob; Kydd, Robert; Micali, Vince [Eskom (South Africa)

    2008-05-15

    The WEC Committee on the Performance of Generating Plant (PGP) has been collecting and analysing power plant performance statistics worldwide for more than 30 years and has produced regular reports, which include examples of advanced techniques and methods for improving power plant performance through benchmarking. A series of reports from the various working groups was issued in 2008. This reference presents the results of Working Group 4 (WG4). WG4 will monitor the development of power markets, in particular from the market risk management point of view, including operational risks. It will assess various risk management strategies used by market players around the world and develop recommendations for a wider deployment of successful strategies. The report covers the project approach and outcomes.

  4. Assessments and applications to enhance human reliability and reduce risk during less-than-full-power operations

    International Nuclear Information System (INIS)

    Hannaman, G.W.; Singh, A.

    1992-01-01

    Study of events, interviews with plant personnel, and applications of risk studies indicate that the risk of a potential accident during less-than-full-power (LTFP) operation is becoming a greater fraction of the risk as improvements are made to the full-power operations. Industry efforts have been increased to reduce risk and the cost of shutdown operations. These efforts consider the development and application of advanced tools to help utilities proactively identify issues and develop contingencies and interventions to enhance reliability and reduce risk of low-power operations at nuclear power plants. The role for human reliability assessments is to help improve utility outage planning to better achieve schedule and risk control objectives. Improvements are expected to include intervention tools to identify and reduce human error, definition of new instructional modules, and prioritization of risk reduction issues for operators. The Electric Power Research Institute is sponsoring a project to address the identification and quantification of factors that affect human reliability during LTFP operation of nuclear power plants. The results of this project are expected to promote the development of proactively applied interventions and contingencies for enhanced human reliability during shutdown operations

  5. Power plant chemical technology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    17 contributions covering topies of fossil fuel combustion, flue gas cleaning, power plant materials, corrosion, water/steam cycle chemistry, monitoring and control were presented at the annual meeting devoted to Power Plant Chemical Technology 1996 at Kolding (Denmark) 4-6 September 1996. (EG)

  6. Plant specific risk informed decision making -a vision for Indian PHWR

    International Nuclear Information System (INIS)

    Guptan, Rajee; Mohan, Nalini; Ghadge, S.G.; Bajaj, S.S.

    2006-01-01

    The objective of Nuclear Power Plant (NPP) safety is to ensure and demonstrate that the risk from NPP to public and plant personnel is acceptably low. As a supplement to the deterministic approach, use of probabilistic techniques has been gaining grounds. Probabilistic Safety Assessment (PSA) is a popular international practice to calculate plant risk to the public, environment and plant personnel, in the event of an accident taking place in the plant. The risk posed by Nuclear Reactors to the Public at large is a very important issue in the public acceptance of a Nuclear Power Programme in any country. Risk Definition, generally accepted at present as the measure of possibility for an accidental event and severity of its effects to occur, simultaneously comprises both the probability (frequency) of potential damage occurrence and extent of this damage. NPCIL' s vision is to provide safe, reliable and cost effective energy to the nation by ensuring safe operation of the plants, limiting radiation exposure to plant personnel and public within prescribed limits. To achieve this vision our mission is to enhance the technical competency, resources and the awareness towards improved safety culture specific to Probabilistic Safety Assessment for applying PSA Studies to Risk Informed Decision making. This mission translates into the goal of completion of full scope PSA, with the co-operation and synergetic efforts of the Head quarters and Operating Station experts. NPCIL will then be self sufficient in applying Probabilistic Studies in Risk Informed Decision making to minimize risk and back fitting design changes to optimize the existing design and operating practices, thus providing for safe, reliable and cost effective energy to the nation. (author)

  7. Nuclear power plant decommissioning

    International Nuclear Information System (INIS)

    Yaziz Yunus

    1986-01-01

    A number of issues have to be taken into account before the introduction of any nuclear power plant in any country. These issues include reactor safety (site and operational), waste disposal and, lastly, the decommissioning of the reactor inself. Because of the radioactive nature of the components, nuclear power plants require a different approach to decommission compared to other plants. Until recently, issues on reactor safety and waste disposal were the main topics discussed. As for reactor decommissioning, the debates have been academic until now. Although reactors have operated for 25 years, decommissioning of retired reactors has simply not been fully planned. But the Shippingport Atomic Power Plant in Pennysylvania, the first large scale power reactor to be retired, is now being decommissioned. The work has rekindled the debate in the light of reality. Outside the United States, decommissioning is also being confronted on a new plane. (author)

  8. A computerized event and maintenance data system at Loviisa nuclear power plant

    International Nuclear Information System (INIS)

    Jankala, K.E.; Saarelainen, P.; Vaurio, J.K.

    1993-01-01

    An on-line failure and maintenance event data system (which is a part of the Loviisa power plant information system) is described as developed and implemented at the Loviisa power plant. The system has been in operation since 1989, and the data base now covers more than 10 years of operation. The system contains a complete unavailability history, i.e. failures, repairs, replacements, scheduled or unscheduled preventive maintenance and periodic testing or service actions for any component that is relevant to plant safety, risk or economic production. The data base provides useful feedback from operating experience and can support e.g. studies on optimal maintenance and testing, planning of spare parts inventory and repair resources, updating of reliability parameters for risk studies, etc. (Z.S.) 4 refs

  9. Study on aging management of fire protection system in nuclear power plant

    International Nuclear Information System (INIS)

    Fang Huasong; Du Yu; Li Jianwen; Shi Haining; Tu Fengsheng

    2010-01-01

    Fire prevention, fire fighting and fire automatic alarms are three aspects which be included in fire protection system in nuclear power plants. The fire protection system can protect personnel, equipment etc in the fire, so their performance will have a direct influence on the safe operation in nuclear power plants. The disabled accidents caused by aging have happened continuously with the extension of time in the fire protection system, which is the major security risk during the running time in nuclear power plants. In view of the importance of fire protection system and the severity of aging problems, the aging are highly valued by the plant operators and related organizations. Though the feedback of operating experience in nuclear power plant, the impact of the fire-fighting equipment aging on system performance and reliability be assessed, the aging sensitive equipment be selected to carry out the aging analysis and to guide the management and maintenance to guarantee the healthy operation in life time of fire protection system in nuclear power plant. (authors)

  10. The financing of nuclear power plants

    International Nuclear Information System (INIS)

    Taylor, M.

    2009-01-01

    not disadvantage NPPs. Long-term arrangements may be necessary to provide certainty for investors in NPPs, reflecting the long-term nature of nuclear power projects. Where reducing CO 2 emissions is to act as an incentive for investments in nuclear power, the government may need to provide some guarantees that policy measures will keep carbon prices at sufficiently high levels. In countries where there are large utilities with the financial strength to invest directly in new NPPs, or where there are well-resourced foreign utilities willing to make such investments, fully commercial financing may be possible. However, in other cases it may prove impossible for a nuclear power plant project to go ahead without direct or indirect public sector financial support, which would reduce the investment risks to acceptable levels. Public sector financial support could involve supporting a state-owned utility in making nuclear power plant investments, providing support to private sector utilities through loan guarantees, tax credits or other measures, or establishing public-private partnerships. However, governments should ensure that, overall, investment risk remains appropriately shared with the private sector

  11. The role of NOSA five-star management system for occupational management of nuclear power plants

    International Nuclear Information System (INIS)

    Zhang Qin

    2011-01-01

    The occupational safety management of nuclear power plant is developed towards integrated management, risk management, process management, all-round and full staff participation. Appropriate management method integrated with nuclear power plant safety, health and environmental protection could be organically combined with the nuclear safety operation management system, and could jointly lay a solid foundation for building up good nuclear safety culture. NOSA five-star management system is such a kind of risk management based on safety, health and environmental management system, with an aim to protect the personal safety. The concepts of NOSA management and nuclear safety culture are coincident, with strong workability, and meeting the need of nuclear power plant occupational safety management. Adopting NOSA five-star management system and keeping continuous improvement is one of the effective ways to improve the level of occupational safety management of nuclear power plant. It can be organically combined with nuclear safety operation management system and continuously improved safety culture to play an important role in improving the safety and economics of nuclear power plant. (author)

  12. The end of cheap electric power from nuclear power plants. 2. ed.

    International Nuclear Information System (INIS)

    Franke, J.; Viefhues, D.

    1984-04-01

    The economic efficiency of a nuclear power plant is compared with that of a coal-fired power plant of the same size. A technical and economic computer model was developed which took account of the power plant and all its units as well as the fuel cycle (including intermediate storage and reprocessing). It was found that future nuclear power plants will be inferior to coal-fired power plants in all economic respects. Further, there was no load range in which the cost of electric power generation was more favourable in nuclear power plants than in coal-fired power plants. (orig./HSCH) [de

  13. Hand-calculation technique for the evaluation of public risk from a severe accident at a nuclear power plant

    International Nuclear Information System (INIS)

    Linn, M.A.; Schmoyer, R.E.

    1993-01-01

    The Nuclear Regulatory Commission (NRC) is in the process of promulgating a proposed rule 10 CFR Part 54, ''Requirements for Renewal of Operating Licensees for Nuclear Power Plants,'' which will allow licenses to renew the operating licenses on their nuclear power plants for an additional 20 years beyond the original 40-year limit. A Generic Environmental Impact Statement (GEIS) prepared by the Oak Ridge National Laboratory (ORNL) in conjunction with and for the Nuclear Regulatory Commission to assess the environmental issues associated with this proposed rule. The evaluation of the environmental impact from postulated severe accidents was included in the GEIS. During this evaluation of postulated severe accidents, a method was developed to estimate the public health consequences of atmospheric releases from severe accidents that is much simpler to use than existing consequence computer codes. From the results of this work, it is concluded that the simplified methodology does provide reasonable and conservative estimates of public risk from atmospheric releases from severe accidents

  14. Financing of nuclear power plant using resources of power generation

    International Nuclear Information System (INIS)

    Slechta, V.; Milackova, H.

    1987-01-01

    It is proved that during the lifetime of a power plant, financial resources are produced from depreciation and from the profit for the delivered electrical power in an amount allowing to meet the cost of construction, interests of credits, the corporation taxes, and the means usable by the utility for simple reproduction of the power plant, additional investment, or for the ultimate decommissioning of the nuclear power plant. The considerations are simplified to 1 MW of installed capacity of a WWER-440 nuclear power plant. The breakdown is shown of the profit and the depreciation over the power plant lifetime, the resources of regular payments of credit instalments for the construction and the method of its calculation, and the income for the state budget and for the utility during the plant liofetime. (J.B.). 5 tabs., 5 refs

  15. Development of methods for the evaluation and reduction of risk factors for the maintenance of nuclear power plants

    International Nuclear Information System (INIS)

    Preuss, W.; Ogurek, K.H.

    1988-01-01

    The maintenance of a nuclear power plant is an essential requirement for its safe operation. Recent experience has however revealed increasingly more deviations and disturbances associated with maintenance work - in particular related to human error. The investigations should contribute to the further improvement of the conditions for safe and optimal maintenance procedures and thus minimize the risk of disturbances arising from them. The first step of the investigation is presented here, in which the methodological preliminary work was carried out and a suitable procedure developed. A basis was provided by means of extensive literature research and analysis. Additional information was obtained through discussions with experts (research workers as well as plant operational management). In particular suitable techniques of investigation and analysis are presented in detail, the problem structure of the field of investigation bas been worked out, and a methodology for the evaluation of data has been developed. Furthermore criteria have been formulated with which nuclear power plants and maintenance processes can be choosen for an economic way of investigation, and a procedure is presented which serves the investigator to check and to improve the methodology. Finally, proposals for further investigations are given. (orig.) [de

  16. Nuclear Power Plants (Rev.)

    Energy Technology Data Exchange (ETDEWEB)

    Lyerly, Ray L.; Mitchell III, Walter [Southern Nuclear Engineering, Inc.

    1973-01-01

    Projected energy requirements for the future suggest that we must employ atomic energy to generate electric power or face depletion of our fossil-fuel resources—coal, oil, and gas. In short, both conservation and economic considerations will require us to use nuclear energy to generate the electricity that supports our civilization. Until we reach the time when nuclear power plants are as common as fossil-fueled or hydroelectric plants, many people will wonder how the nuclear plants work, how much they cost, where they are located, and what kinds of reactors they use. The purpose of this booklet is to answer these questions. In doing so, it will consider only central station plants, which are those that provide electric power for established utility systems.

  17. Probabilistic safety assessment- a tool for configuration control of nuclear power plants

    International Nuclear Information System (INIS)

    Vijaya, A.K.; Guptan, Rajee; Mohan, Nalini; Ghadge, S.G.; Bajaj, S.S.

    2006-01-01

    A comprehensive configuration control programme implies a sophisticated set of risk related measures to manage and control concurrent unavailabilities of components, the possibility of functional alternative components, the outage times of the unavailable components and the frequency of critical configurations. These measures are implemented through operational and maintenance activities such as maintenance and test scheduling and scheduling of operational realignments. An appropriate risk based configuration control programme would enable plant personnel to maintain the risk level of the nuclear power plant within an acceptable range during all the operational regimes. Use of plant specific PSA to support configuration control makes it risk based. The PSA can help to identify the measures needed according to the situation to reduce risk to acceptable level. The main benefit of establishing a risk based configuration control programme is the reduction of risk peaks and the control of cumulative or average risk. It helps to ensure that as far as possible, the plant does not enter the critical, high risk situations and other risk significant configurations are avoided A plant specific PSA along with a 'Risk Monitor' can be used as an efficient tool for Configuration Control. (author)

  18. 76 FR 1469 - Calvert Cliffs Nuclear Power Plant, LLC; Calvert Cliffs Nuclear Power Plant, Unit Nos. 1 and 2...

    Science.gov (United States)

    2011-01-10

    ... Nuclear Power Plant, LLC; Calvert Cliffs Nuclear Power Plant, Unit Nos. 1 and 2 Environmental Assessment... Plant, LLC, the licensee, for operation of the Calvert Cliffs Nuclear Power Plant, Unit Nos. 1 and 2... Impact Statement for License Renewal of Nuclear Plants, Calvert Cliffs Nuclear Power Plant (NUREG-1437...

  19. MERCURY EMISSIONS FROM COAL FIRED POWER PLANTS LOCAL IMPACTS ON HUMAN HEALTH RISK.

    Energy Technology Data Exchange (ETDEWEB)

    SULLIVAN, T.M.; BOWERMAN, B.; ADAMS, J.; LIPFERT, F.; MORRIS, S.M.; BANDO, A.; PENA, R.; BLAKE, R.

    2005-12-01

    A thorough quantitative understanding of the processes of mercury emissions, deposition, and translocation through the food chain is currently not available. Complex atmospheric chemistry and dispersion models are required to predict concentration and deposition contributions, and aquatic process models are required to predict effects on fish. However, there are uncertainties in all of these predictions. Therefore, the most reliable method of understanding impacts of coal-fired power plants on Hg deposition is from empirical data. A review of the literature on mercury deposition around sources including coal-fired power plants found studies covering local mercury concentrations in soil, vegetation, and animals (fish and cows). There is strong evidence of enhanced local deposition within 3 km of the chlor-alkali plants, with elevated soil concentrations and estimated deposition rates of 10 times background. For coal-fired power plants, the data show that atmospheric deposition of Hg may be slightly enhanced. On the scale of a few km, modeling suggests that wet deposition may be increased by a factor of two or three over background. The measured data suggest lower increases of 15% or less. The effects of coal-fired plants seem to be less than 10% of total deposition on a national scale, based on emissions and global modeling. The following summarizes our findings from published reports on the impacts of local deposition. In terms of excesses over background the following increments have been observed within a few km of the plant: (1) local soil concentration Hg increments of 30%-60%, (2) sediment increments of 18-30%, (3) wet deposition increments of 11-12%, and (4) fish Hg increments of about 5-6%, based on an empirical finding that fish concentrations are proportional to the square root of deposition. Important uncertainties include possible reductions of RGM to Hg{sub 0} in power plant plumes and the role of water chemistry in the relationship between Hg

  20. The economics of long-term operation of nuclear power plants

    International Nuclear Information System (INIS)

    Lokhov, Alexey; Huerta, Alejandro; Dufresne, Luc; Giraud, Anne; Osouf, Nicolas

    2012-01-01

    Refurbishment and long-term operation (LTO) of existing nuclear power plants (NPPs) today are crucial to the competitiveness of the nuclear industry in OECD countries as existing nuclear power plants produce base-load power at a reliable cost. A number of nuclear power plants, most notably 73 units in the United States (up to 2012), have been granted lifetime extensions of up to 60 years, a development that is being keenly watched in other OECD countries. In many of these (e.g. France, Switzerland), there is no legal end to the operating licence, but continued operation is based on the outcomes of periodic safety reviews. This study analyses technical and economic data on the upgrade and lifetime extension experience in OECD countries. A multi-criteria assessment methodology is used considering various factors and parameters reflecting current and future financial conditions of operation, political and regulatory risks, the state of the plants' equipment and the general role of nuclear power in the country's energy policy. The report shows that long-term operation of nuclear power plants has significant economic advantages for most utilities envisaging LTO programmes. In most cases, the continued operation of NPPs for at least ten more years is profitable even taking into account the additional costs of post-Fukushima modifications, and remains cost-effective compared to alternative replacement sources

  1. The classification of knowledge and expertise in Finnish nuclear power plants

    International Nuclear Information System (INIS)

    Kuronen, T.; Rintala, N.

    2006-01-01

    The difficulties in sharing tacit knowledge may compromise the safe performance of high-reliability organisations. This threat has been recognised in nuclear power plants worldwide, owing to the risk of simultaneous retirements. In this study, the nature of tacit knowledge in Finnish nuclear power plants was examined and the expertise of nuclear workers modelled. The results of this interview study showed that the tacit nuclear knowledge can be classified in two dimensions: technical and contextual. According to this classification, the employees in plants can be categorised in four categories: the experts; the novices; the technical specialists; the context sensitives. (author)

  2. PRA Procedures Guide: a guide to the performance of probabilistic risk assessments for nuclear power plants. Final report, Volume 1 - Chapters 1-8

    International Nuclear Information System (INIS)

    1983-01-01

    This document, the Probabilistic Risk Assessment (PRA) Procedures Guide, is intended to provide an overview of the risk-assessment field as it exists today and to identify acceptable techniques for the systematic assessment of the risk from nuclear power plants. Topics discussed include: organization of PRA; accident-sequence definition and system modeling; human-reliability analysis; data-base development; accident-sequence quantification; physical processes of core-melt accidents; and radionuclide release and transport

  3. Hybrid wind-power-distillation plant

    Directory of Open Access Journals (Sweden)

    Ninić Neven

    2012-01-01

    Full Text Available This paper reports and elaborates on the idea of a solar distiller and an offshore wind power plant operating together. The subject under discussion is a single-stage solar distillation plant with vaporization, using adiabatic expansion in the gravitational field inside a wind power plant supporting column. This scheme divides investment costs for electric power and distillate production. In the region of the Adriatic Sea, all electric power produced could be “converted” to hydrogen using less than 10% of the distillate produced.

  4. Issues and measures in the design process from the perspective of risk management of construction projects. study of power plant construction projects accident cases

    International Nuclear Information System (INIS)

    Iwahara, Hirohiko; Shiraki, Wataru; Inomo, Hitoshi; Hasegawa, Syuichi

    2015-01-01

    Construction of power plants, foundation work, consisting of a wide variety of construction work, such as plant equipment work. And, civil engineering, technician electrical such as different engineering field, is a comprehensive construction project that works for the design conditions of the structure. However, if the cooperation design conditions is not sufficient, as a construction project, the optimal structures may not be said to have been built. As a result, total cost or increased, including the initial cost of the end construction projects, it is be a cause of the accident. Previous studies, plant equipment construction, is related to safety management and risk of foundation work such as individual construction were many. In this paper, as an example the power plant construction, and performs the following discussion from the point of view of risk management of large-scale construction projects that these individual construction work together with each other. The importance of design conditions cooperation, (1) 'Challenges and countermeasures of ordering method of construction projects', to verify from the (2) 'actually happened substation foundation displacement accident'. And on whether or not the construction project order institutions can be involved in the design from the site preparation stage, we study (3) for 'construction work scope and risk control the construction project ordering institutions to implement' the risk to the natural disaster (earthquake). From these, we describe the challenges and measures in the construction project of the design process. (author)

  5. Power plants 2009. Lectures

    International Nuclear Information System (INIS)

    2009-01-01

    Within the Annual Conference 2009 of the VGB PowerTech e.V. (Essen, Federal Republic of Germany) from 23rd to 25th May, 2009, in Lyon (France) the following lectures were held: (1) Electricity demand, consequences of the financial and economic crisis - Current overview 2020 for the EU-27 (Hans ten Berge); (2) Status and perspectives of the electricity generation mix in France (Bernard Dupraz); (3) European electricity grid - status and perspective (Dominique Maillard); (4) Technologies and acceptance in the European energy market (Gordon MacKerran); (5) EPR construction in Finland, China, France, (Claude Jaouen); (6) EPR Flamanville 3: A project on the path towards nuclear revival (Jacques Alary); (7) Worldwide nuclear Revival and acceptance (Luc Geraets); (8) An overview on the status of final disposal of radioactive wastes worldwide (Piet Zuidema); (9) Who needs pumped storage plants? PSP are partner to grid stability and renewable energies (Hans-Christoph Funke); (10) Sustainable use of water resources to generate electricity safely and efficiently (Patrick Tourasse); (11) The growth strategy of RWE Innogy - Role of RES in RWE strategy (Fritz Vahrenholt); (12) Solar technologies towards grid parity - key factors and timeframe (G. Gigliucci); (13) Overview on CCS technologies and results of Vattenfalls oxyfuel pilot plant (Philippe Paelinck); (14) Development perspectives of lignite-based IGCC-plants with CCS (Dietmar Keller); (15) Post combustion capture plants - concept and plant integration (Wolfgang Schreier); (16) CCS fossil power generation in a carbon constraint world (Daniel Hofmann); (17) CEZ group strategy in Central and South Eastern Europe (Jan Zizka); (18) Strategy and projects of DONG Energy (Jens Erik Pedersen); (19) E.ON coal-based power generation of the future - The highly efficient power plant and downstream separation of carbon dioxide (Gerhard Seibel); (20) Final sage of first supercritical 460 MW e l. CFB Boiler construction - firs

  6. Efficient improvement of nuclear power plant safety by reorganization of risk-informed safety importance evaluation methods for piping welded portions

    Energy Technology Data Exchange (ETDEWEB)

    Irie, Takashi; Hanafusa, Hidemitsu; Suyama, Takeshi [Institute of Nuclear Safety System, Inc., Mihama, Fukui (Japan); Morota, Hidetsugu; Kojima, Sigeo; Mizuno, Yoshinobu [Computer Software Development Co., Ltd., Tokyo (Japan)

    2002-09-01

    In this work, risk information was used to evaluate the safety importance of piping welded portions which were important for plant operation and maintenance of nuclear power plants. There are two types of risk-informed safety importance evaluation methods, namely the ASME method and the EPRI method. Since both methods have advantages and disadvantages, elements of each method were combined and reorganized. Considerations included whether the degradation mechanisms would be objectively evaluated and whether plant safety would be efficiently improved. The most objective and efficient method was as follows. Piping failure potential is quantitatively and objectively evaluated for failure with probabilistic fracture mechanics (PFM) and for other degradation mechanisms with empirical failure rates, and conditional core damage probability (CCDP) is calculated with PSA. This method reduces the inspected segment numbers to 1/4 of the deterministic method and increases the ratio of risk, which is covered by the inspected segments, to total risk from 80% of the deterministic method to 95%. Piping inspection numbers decreased for safety injection systems that were required the inspections by the deterministic method. Piping inspections were required for part of main feed water and main steam systems that were not required the inspections by the deterministic method. (author)

  7. Chemistry in power plants 2011

    International Nuclear Information System (INIS)

    2011-01-01

    Within the VGB Powertech conference from 25th to 27th October, 2011, in Munich (Federal Republic of Germany), the following lectures and poster contributions were presented: (1) The revised VGB standard for water-steam-cycle Chemistry; (2) Switchover from neutral operation to oxygen treatment at the power station Stuttgart-Muenster of EnBW Kraftwerke AG; (3) Steam contamination with degradation products of organic matters present in the feedwater of the Lanxess-Rubber cogeneration plant; (4) Laboratory scale on-line noble metal deposition experiments simulating BWR plant conditions; (5) Building a new demin installation for the power plant EPZ in Borssele; (6) Replacement of the cooling tower installations in the nuclear power plant Goesgen-Daenien AG; (7) Aging of IEX resins in demin plants - Cost optimisation by adaptation of regenerants; (8) The largest DOW trademark EDI System at a combined cycled plant in Europe; (9) Upgrading river Main water to boiler feed water - Experiences with ultrafiltration; (10) Experiences with treatment of the water-steam-cycle in the RDF power plant Nehlsen Stavenhagen with film-forming amines; (11) Comparative modelling of the bubbles thermal collapse and cavitations for estimation of bubbles collapse influence; (12) Overcoming the steam quality - issues from an HRSG for the production of process steam; (13) Legionella - new requirements for power plant operation; (14) How the right chemistry in the FGD helps to improve the removal in the waste water treatment plant; (15) High efficiency filtration in dry/semi-dry FGD plants; (16) Expanding the variety of renewable fuels in the biomass power plant Timelkam using the chemical input control; (17) Corrosion, operating experiences and process improvements to increase the availability and operating time of the biomass power plant Timelkam; (18) The influence of temperature on the measurement of the conductivity of highly diluted solutions; (19) A multiparameter instrumentation approach

  8. Control system security in nuclear power plant

    International Nuclear Information System (INIS)

    Li Jianghai; Huang Xiaojin

    2012-01-01

    The digitalization and networking of control systems in nuclear power plants has brought significant improvements in system control, operation and maintenance. However, the highly digitalized control system also introduces additional security vulnerabilities. Moreover, the replacement of conventional proprietary systems with common protocols, software and devices makes these vulnerabilities easy to be exploited. Through the interaction between control systems and the physical world, security issues in control systems impose high risks on health, safety and environment. These security issues may even cause damages of critical infrastructures and threaten national security. The importance of control system security by reviewing several control system security incidents that happened in nuclear power plants was showed in recent years. Several key difficulties in addressing these security issues were described. Finally, existing researches on control system security and propose several promising research directions were reviewed. (authors)

  9. Risk-based plant performance indicators

    International Nuclear Information System (INIS)

    Boccio, J.L.; Azarm, M.A.; Hall, R.E.

    1991-01-01

    Tasked by the 1979 President's Commission on the Accident at Three Mile Island, the U.S. nuclear power industry has put into place a performance indicator program as one means for showing a demonstrable record of achievement. Largely through the efforts of the Institute of Nuclear Power Operations (INPO), plant performance data has, since 1983, been collected and analyzed to aid utility management in measuring their plants' performance progress. The U.S. Nuclear Regulatory Commission (NRC) has also developed a set of performance indicators. This program, conducted by NRC's Office for the Analysis and Evaluation of Operational Data (AEOD), is structured to present information on plant operational performance in a manner that could enhance the staff's ability to recognize changes in the safety performance. Both organizations recognized that performance indicators have limitations and could be subject to misinterpretation and misuse with the potential for an adverse impact on safety. This paper reports on performance indicators presently in use, e.g., unplanned automatic scrams, unplanned safety system actuation, safety system failures, etc., which are logically related to safety. But, a reliability/risk-based method for evaluating either individual indicators or an aggregated set of indicators is not yet available

  10. Thermal power plant design and operation

    CERN Document Server

    Sarkar, Dipak

    2015-01-01

    Thermal Power Plant: Design and Operation deals with various aspects of a thermal power plant, providing a new dimension to the subject, with focus on operating practices and troubleshooting, as well as technology and design. Its author has a 40-long association with thermal power plants in design as well as field engineering, sharing his experience with professional engineers under various training capacities, such as training programs for graduate engineers and operating personnel. Thermal Power Plant presents practical content on coal-, gas-, oil-, peat- and biomass-fueled thermal power

  11. Small-scale power plant potential in Finland

    International Nuclear Information System (INIS)

    Helynen, S.

    1993-01-01

    The presentation discusses the small-scale power plant potential in Finland. The study of the potential is limited to W-scale power plants producing both electric power and heat using solid fuels. The basic power plant dimensioning and electric power load determination is based on traditional boiler and gas turbine technology. The possible sites for power plants are communities using district heating, and industrialized sites needing process steam or heat. In 1990 70 % (17 TWh) of district heat was produced by gas turbines. Ten communities have an own back-pressure power plant, and 40 communities buy heat from industrial plants, owing back-pressure power generation. Additionally about 40 communes buy district heat from companies, owned by power companies and industry. Estimates of small-scale power plant potential has been made plant wise on the basis of district heat loads and industrial heat needs. The scale of the plants has been limited to scale 3 MWe or more. The choosing of the fuel depends on the local conditions. The cheapest indigenous fuels in many communes are industrial wood wastes, and both milled and sod peat. The potential of steam technology based small-scale power plants has been estimated to be about 50 plants in 1992/1993, the total power of which is 220-260 MW. The largest estimate is base situation, in which there would be energy cooperation between the communes and industry. The fuel used by the power plants would be about 5.4-6.6 TWh/a corresponding to 270-330 million FIM/a. The total investment costs of the plants would be about 2.0 billion FIM. The plants would employ about 250 persons, and the fuel supply (wood or peat) about 100 persons

  12. Power control of the Angra-2 Nuclear Power Plant

    International Nuclear Information System (INIS)

    Souza Mendes, J.E. de

    1986-01-01

    The systems for the power control of the Nuclear Power Plant Angra 2 have a high degree of automation so that few operator actions are required during power operation. The power control strategy and the operation principles of the control systems, here presented, make possible a great flexibility of the Plant operation. (Author) [pt

  13. Organizing nuclear power plant operation

    International Nuclear Information System (INIS)

    Adams, H.W.; Rekittke, K.

    1987-01-01

    With the preliminary culmination in the convoy plants of the high standard of engineered safeguards in German nuclear power plants developed over the past twenty years, the interest of operators has now increasingly turned to problems which had not been in the focus of attention before. One of these problems is the organization of nuclear power plant operation. In order to enlarge the basis of knowledge, which is documented also in the rules published by the Kerntechnischer Ausschuss (Nuclear Technology Committee), the German Federal Minister of the Interior has commissioned a study of the organizational structures of nuclear power plants. The findings of that study are covered in the article. Two representative nuclear power plants in the Federal Republic of Germany were selected for the study, one of them a single-unit plant run by an independent operating company in the form of a private company under German law (GmbH), the other a dual-unit plant operated as a dependent unit of a utility. The two enterprises have different structures of organization. (orig.) [de

  14. A re-evaluation of nuclear plant offsite power supplies

    International Nuclear Information System (INIS)

    William E Berger; Robert E Henry

    2005-01-01

    Full text of publication follows: De-regulation of the electric power industry has resulted in separate ownership of the transmission and power generation facilities as well as a revised format for operating the transmission facilities. Currently we see the transfer of large blocks of bulk power between markets which can impact the voltage regulation at the offsite power supply. Where Nuclear Plant operations once knew with a large degree of certainty the operating range of the system supplying the offsite power supply, this may no longer be the case and more challenges to the safety systems could result. These challenges may manifest themselves as either a loss of offsite power or voltage levels approaching the degraded level setpoints. In this paper we will first explore what challenges are caused by deregulation and how they impact offsite power supply operations. Next we will incorporate the knowledge grained regarding accidents and consequences from the Individual Plant Evaluations (IPE's) to see how the offsite power supply could be operated to mitigate the challenges and extend the capacity of the auxiliary power system. Various scenarios will be examined using the Modular Accident Analysis Program (MAAP) as an integral plant model. MAAP simulations that include both the plant thermal hydraulic responses and corresponding electric power demand are presented to demonstrate the impact of alternate approaches to offsite power system operation. The original design phase of the offsite and onsite power distribution system was based on a criterion relating to the starting of all safety loads if a safety injection signal was present independent of the accident or its progression. The IPE and risk informed insights that are readily available today will be applied in the re-analyses of the offsite distribution system response. (authors)

  15. Modernization of existing power plants. Progress in automation and process control/observation

    International Nuclear Information System (INIS)

    Hanna, I.

    1996-01-01

    Numerous power plants are now getting on in years, and their owners have to face the question 'New plant or upgrade job ?'. Experience in the past few years has shown that in many cases modernization/upgrading of existing plants is a more favorable option than building a complete new power plant. Advantages like lower capital investment costs and avoidance of licensing risks for new plants constitute important motives for choosing the upgrade option in numerous power plants modernization projects. The defined objective here is to ensure the units' operating capability for another 20 to 25 years, sometimes supplemented by meticulous compliance with current environmental impact legislation. Another cogent argument emerges from automation engineering advances in modern-day control systems which make an effective contribution to meeting upgrading objective like: equipment/material -friendly operation, extended useful lifetime, enhanced plant reliability, enhanced plant availability, improved plant efficiency, optimized staffing levels, enhanced cost-effectiveness, compliance with today's international standards. In this context special attention is paid to the economical aspects and to the increase of plant availability. (author). 6 figs

  16. Advanced power plant materials, design and technology

    Energy Technology Data Exchange (ETDEWEB)

    Roddy, D. (ed.) [Newcastle University (United Kingdom). Sir Joseph Swan Institute

    2010-07-01

    The book is a comprehensive reference on the state of the art of gas-fired and coal-fired power plants, their major components and performance improvement options. Selected chapters are: Integrated gasification combined cycle (IGCC) power plant design and technology by Y. Zhu, and H. C. Frey; Improving thermal cycle efficiency in advanced power plants: water and steam chemistry and materials performance by B. Dooley; Advanced carbon dioxide (CO{sub 2}) gas separation membrane development for power plants by A. Basile, F. Gallucci, and P. Morrone; Advanced flue gas cleaning systems for sulphur oxides (SOx), nitrogen oxides (NOx) and mercury emissions control in power plants by S. Miller and B.G. Miller; Advanced flue gas dedusting systems and filters for ash and particulate emissions control in power plants by B.G. Miller; Advanced sensors for combustion monitoring in power plants: towards smart high-density sensor networks by M. Yu and A.K. Gupta; Advanced monitoring and process control technology for coal-fired power plants by Y. Yan; Low-rank coal properties, upgrading and utilisation for improving the fuel flexibility of advanced power plants by T. Dlouhy; Development and integration of underground coal gasification (UCG) for improving the environmental impact of advanced power plants by M. Green; Development and application of carbon dioxide (CO{sub 2}) storage for improving the environmental impact of advanced power plants by B. McPherson; and Advanced technologies for syngas and hydrogen (H{sub 2}) production from fossil-fuel feedstocks in power plants by P. Chiesa.

  17. Lessons learned from first generation nuclear plant probabalistic risk assessments

    International Nuclear Information System (INIS)

    Garrick, B.J.

    1984-01-01

    The paper by Garrick summarizes the state-of-the-art in what are perhaps the most archetypical probabilistic risk assessments (PRAs). Because of its unique regulatory environment and because of the high levels of perceived (not necessarily actual) risk, the nuclear industry more than any other has been concerned with quantitative risk analysis. Garrick's paper summarizes the lessons learned from ten PRA's conducted in the nuclear industry, including six that can be characterized as full-scope risk studies. Most of the quantitative data, though, came from two especially thorough studies done for the Zion and Indian Point power plants, operated by Commonwealth Edison and Consolidated Edison respectively. The principal conclusions of the Garrick survey are that the public risk (from radiation release) is now known to be very small for commercial nuclear power plants, but that the risk to utilities (from core damage) is somewhat larger. Significant radiation releases require both core meltdown -- an event occurring only about once every 10,000 reactor-years -- and containment failure, occurring only about once in every hundred meltdowns

  18. Auxiliary feedwater system risk-based inspection guide for the South Texas Project nuclear power plant

    International Nuclear Information System (INIS)

    Bumgardner, J.D.; Nickolaus, J.R.; Moffitt, N.E.; Gore, B.F.; Vo, T.V.

    1993-12-01

    In a study sponsored by the US Nuclear Regulatory Commission (NRC), Pacific Northwest Laboratory has developed and applied a methodology for deriving plant-specific risk-based inspection guidance for the auxiliary feedwater (AFW) system at pressurized water reactors that have not undergone probabilistic risk assessment (PRA). This methodology uses existing PRA results and plant operating experience information. Existing PRA-based inspection guidance information recently developed for the NRC for various plants was used to identify generic component failure modes. This information was then combined with plant-specific and industry-wide component information and failure data to identify failure modes and failure mechanisms for the AFW system at the selected plants. South Texas Project was selected as a plant for study. The product of this effort is a prioritized listing of AFW failures which have occurred at the plant and at other PWRs. This listing is intended for use by the NRC inspectors in preparation of inspection plans addressing AFW risk important components at the South Texas Project plant

  19. Auxiliary feedwater system risk-based inspection guide for the H. B. Robinson nuclear power plant

    International Nuclear Information System (INIS)

    Moffitt, N.E.; Lloyd, R.C.; Gore, B.F.; Vo, T.V.; Garner, L.W.

    1993-08-01

    In a study sponsored by the US Nuclear Regulatory Commission (NRC), Pacific Northwest Laboratory has developed and applied a methodology for deriving plant-specific risk-based inspection guidance for the auxiliary feedwater (AFW) system at pressurized water reactors that have not undergone probabilistic risk assessment (PRA). This methodology uses existing PRA results and plant operating experience information. Existing PRA-based inspection guidance information recently developed for the NRC for various plants was used to identify generic component failure modes. This information was then combined with plant-specific and industry-wide component information and failure data to identify failure modes and failure mechanisms for the AFW system at the selected plants. H. B. Robinson was selected as one of a series of plants for study. The product of this effort is a prioritized listing of AFW failures which have occurred at the plant and at other PWRs. This listing is intended for use by NRC inspectors in the preparation of inspection plans addressing AFW risk-important components at the H. B. Robinson plant

  20. Auxiliary feedwater system risk-based inspection guide for the J.M. Farley Nuclear Power Plant

    International Nuclear Information System (INIS)

    Vo, T.V.; Pugh, R.; Gore, B.F.; Harrison, D.G.

    1990-10-01

    In a study sponsored by the US Nuclear Regulatory Commission (NRC), Pacific Northwest Laboratory has developed and applied a methodology for deriving plant-specific risk-based inspection guidance for the auxiliary feedwater (AFW) system at pressurized water reactors that have not undergone probabilistic risk assessment(PRA). This methodology uses existing PRA results and plant operating experience information. Existing PRA-based inspection guidance recently developed for the NRC for various plants was used to identify generic component failure modes. This information was then combined with plant-specific and industry-wide component information and failure data to identify failure modes and failure mechanisms for the AFW system at the selected plants. J. M. Farley was selected as the second plant for study. The product of this effort is a prioritized listing of AFW failures which have occurred at the plant and at other PWRs. This listing is intended for use by NRC inspectors in the preparation of inspection plans addressing AFW risk-important at the J. M. Farley plant. 23 refs., 1 fig., 1 tab