• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1601-1602
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• 2007

Steam stop valves of steam turbine in the power plant are at their 100% position and have no movements. Steam control valves, ie governor valves have no movements either at their controlling position on load limit operation. By the way, if there were no change of operation state, steam valves could be sticked mechanically. Because the governor could fail in protecting and controlling steam turbine in case of emergency conditions, the closing test of 100% valve travel must be accomplished periodically for the purpose of testimony of their good conditions. And, As the difference between steam turbine structures exists according to the manufacturer or generation capacity, both steam stop valves and steam control valves differes in structure and operation method. Therefore, it is essential for not only turbine protection but also control for the control engineers to find out composition of steam valves and method of closing test.

• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.287-290
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• 1999

This paper describes an optimal design method of VSI output filter for CVCF system. The cost function is used for design, and all parameters are described in p.u(per unit) so that can be adapted to the change of CVCF rating. The capacitor current feedback scheme is proposed to control the damping ratio of the filter plant to meet the system more stable. This means that the LC resonance can be suppressed well in transient condition and can use the same control gains under the change of system capacity. The validity of the proposed method is well verified with the theoretical analysis and simulation results.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.267-272
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• 2009

The effects of design parameters for small scale hydro power(SSHP) plants due to rainfall condition have been studied. The model to predict hydrologic performance for SSHP plants is used in this study. The results from analysis for rainfall conditions based on KIER model show that the capacity and load factor of SSHP site had large difference between the period. Especially, the hydrologic performance of SSHP site due to rainfall condition of recent period varied in design flowrate sensitively. And also, the methodology represented in this study can be used to decide the primary design specifications of SSHP sites.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.614-618
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• 2009

The effects of design parameters for small scale hydro power(SSHP) plants due to rainfall condition have been studied. The model to predict hydrologic performance for SSHP plants is used in this study. The results from analysis for rainfall conditions based on KIER model show that the capacity and load factor of SSHP site had large difference between the period. Especially, the hydrologic performance of SSHP site such as design flowrate due to rainfall condition of recent period varied sensitively. And also, the methodology represented in this study can be used to decide the primary design specifications of SSHP sites.

• Nuclear Engineering and Technology
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• v.44 no.3
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• pp.297-310
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• 2012

Aging-related degradation of nuclear power plant components is an important aspect to consider in securing the long term safety of the plant, especially the seismic safety, since the degradation of the components affects not only their seismic capacity but their response. This can cause a change in the seismic margin of a component and the overall seismic safety of a system. To better understand the status and characteristics of degradation of components in Nuclear Power Plants (NPPs), the degradation occurrences of components in the U.S. NPPs were identified by reviewing recent publicly available information sources and the characteristics of these occurrences were evaluated and compared to observations from the past. Ten categories of components that are of high risk significance in Korean NPPs were identified, comprising anchorage, concrete, containment, exchanger, filter, piping systems, reactor pressure vessels, structural steel, tanks, and vessels. Software tools were developed to expedite the review process. Results from this review effort were compared to previous data in the literature to characterize the overall degradation trends.

• Environmental and Resource Economics Review
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• v.22 no.2
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• pp.367-391
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• 2013

After the Fukushima nuclear accident, the external costs of generating electricity from nuclear power plants such as additional safety compliance costs and possible accident risk action costs have gained increasing attention from the public, policy-makers and politicians. Consequently, estimates of the external costs of nuclear power are very deliberate issue that is at the center of the controversy in Korea. In this paper, we try to calculate the external costs associated with the safety of the nuclear power plants, particularly focusing on additional safety compliance costs and possible accident risk action costs. To estimate the possible accident risk action costs, we adopt the damages expectation approach that is very similar way from the external cost calculation of Japanese government after the Fukushima accident. In addition, to estimate additional safety compliance costs, we apply the levelized cost of generation method. Furthermore, we perform the sensitivity analysis to examine how much these social costs increase the electricity price rate. Estimation results of the additional security measure cost is 0.53Won/kWh ~ 0.80Won/kWh depending on the capacity factor, giving little change on the nuclear power generation cost. The estimates of possible accident risk action costs could be in the wide range depending on the different damages of the nuclear power accident, probability of the severe nuclear power accident and the capacity factor. The preliminary results show that it is 0.0025Won/kWh ~ 26.4188Won/kWh. After including those two external costs on the generation cost of a nuclear power plant, increasing rate of electricity price is 0.001%~10.0563% under the capacity factor from 70% to 90%. This paper tries to examine the external costs of nuclear power plants, so as to include it into the generation cost and the electricity price. This paper suggests one of the methodologies that we might internalize the nuclear power generations' external cost, including it into the internal generation cost.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.03a
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• pp.239-249
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• 2002

The Turbine Building of nuclear power plant is classified as non safety-related structure. During the operation, there may be possibility the original licensing basis would be changed, which makes non safety-related structure safety-related. Such a change in regulation requires utility to perform seismic qualification for the existing structure and their facilities. Thus it is meaningful to evaluate seismic margin of the existing non-qualified building structure. In addition, in this paper it is shown that a modification to the structure can enhance their seismic capacity.

• Korean Journal of Legislative Studies
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• v.23 no.1
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• pp.151-185
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• 2017

Seoul's One Less Nuclear Power Plant is the major urban energy policy launched in April 2012. Its effort to respond to climate change and energy crisis in the aftermath of the Fukushima nuclear accident turned out very successful, considering huge decrease of energy consumption. However, the question of how the cut of energy consumption was possible remains unanswered. This paper introduces the concept of urban governance capacity as the cause of the success. It is the managing and governing capability to maintain the logical consistency policy system, comprising of policy perception, goals, policy tools and evaluation. Without this logical correspondence between the policy factors, any system including energy regime easily falls apart during the systemic transitional period. Governance capacity provides the integrating framework, so that the system as a whole maintains the internal homeostasis.

• Journal of the Korean Solar Energy Society
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• v.34 no.6
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• pp.19-25
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• 2014

Alternative sources of energy take a higher interest in order to reduce the greenhouse gas under the Climate Change Convention, fossil fuel consumption, and lower social anxiety about nuclear power such as crisis involving the Fukushima plant, problem of obsolete equipment. The energy consumption of agriculture, forestry and fisheries in South Korea is 3,082,000toe by 2011, reliance on electrical energy(35%) and oil(57.2%) is very high with 92.2%. In this study, we examined reserves and available capacity of temperature difference energy for thermal discharge from plant, treated sewage, river water, dam, and agricultural reservoir in rural community. Reserves of unutilized energy are 455,735Tcal/yr in rural community, these accounts for 78% of total reserves 582,385Tcal/y. Thermal discharge from plant has the most reserves of unutilized energy in rural community, it is estimated that it has the reserves of 277,410Tcal/y. Available capacity of unutilized energy in rural community is total 134,147Tcal/y, thermal discharge from plant available for heating is the most 128,035Tcal/y, and it shows in the order of treated sewage 4,318Tcal/y, river water 1,653Tcal/y, and reservoir 141Tcal/y. Elevating temperature area of green house by 2012 is 21,208ha. The amount of energy required for heating the greenhouse a year is dbout 11,365Tcal/y with 8.5% of the total available capacity of unutilized energy.

• Nuclear Engineering and Technology
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• v.53 no.12
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• pp.4114-4121
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• 2021

The Rooppur Nuclear Power Plant (RNPP), the first nuclear power plant in Bangladesh with a capacity of 2.4 GWe, is under construction on the bank of the river Padma, at Rooppur in Bangladesh. Measurement of background radioactivity in the natural environment adjacent to RNPP finds great importance for future perspectives. Soil and sediment samples collected from upstream and downstream positions of the Padma River (adjacent to RNPP) were collected and analyzed by HPGe gamma-ray spectrometry for primordial radionuclides. The average activity concentrations (in Bqkg^-1) of ²²⁶Ra, ²³²Th and ⁴⁰K radionuclides in soil samples were found to be 44.99 ± 3.89, 66.28 ± 6.55 and 553 ± 82.17 respectively. Respective values in sediment samples were found to be 44.59 ± 4.58, 67.64 ± 7.93, 782 ± 108. Relevant radiation hazard indices and dosimetric parameters were calculated and compared with the world average data recommended by US-EPA. Analytical results show non-negligible radiation hazards to the surrounding populace. Measured data will be useful to monitor any change of background radioactivity in the surrounding environment of RNPP following its operation for the generation of nuclear energy.