• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.80-85
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• 2008

A PVIB(Photovoltaic in Building) system is united by a constituent outer covering and can expect dual effects that reduce expenses for the establishment of a PV system. It is a profitable technology because it does not need a building as it is a stand alone PV system. This paper presents design, operational features analysis, and PCS(Power Conditioning System) of grid-connected 30kW PVIB set up on the library of Dongshin University. For a sustainable photovoltaic system in this area, the data of the PVIB system are collected and analyzed by monitoring system using LabView. PCS of the grid-connected PVIB system, also, is designed for optimal operation with characteristics suggested in this paper.

• Transactions of the Korean hydrogen and new energy society
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• v.26 no.5
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• pp.484-492
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• 2015

As our government is actively introducing the RPS (Renewable Portfolio Standards) as a national renewable energy obligation policy, power producers are using the various renewable energy to meet the RPS supply quota since 2012. Recently, it is appling to use power bio-fuel oil in bio-fuel oil demonstration project with power companies. In general, power bio-fuel oils are composed of mixture products of vegetable oil, animal fat, fatty acid ester and waste oil. It is already developing for a power plant as a renewable energy abroad. In Korea, it is studying a 100% combustion and blended combustion of heavy fuel oil and bio-fuel oil. In this study, we investigated fuel characteristics of mixed power bio-fuel oil and its emission performance. Especially, it was reduced emissions of bio-oil in industrial boilers due to bio-fuel properties as compare with fuel oil.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.7
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• pp.35-42
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• 2018

Semi-transparent Photovoltaics (STPV) works as an exterior material replacing windows as well as functioning as a electricity generator. As a result, it also affects the building's heating, cooling and lighting loads. In this study, we used the concept of Net Electricity Benefit(NEB) to conduct a parametric analysis of building energy impact of STPV. The NEB of STPV is from $-1kWh/m^2$ to $6kWh/m^2$. Since NEB represents the amount of energy increase or decrease when STPV is applied compared to the standard window, a value of 0 or less means that the demand for building energy can be increased rather than applying a general window having high thermal performance and high visible light transmittance value. Therefore, it is necessary to perform a comprehensive performance evaluation considering both the performance evaluation based on the existing power generation performance and the influence on the building energy.

• Journal of the Korean Society for Marine Environment & Energy
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• v.14 no.4
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• pp.230-238
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• 2011

The experimental study for the performances of 100 kW marine current turbines (Horizontal Axis Turbine) has been conducted with three cases of 700 mm diameter model in PNU 100 m towing tank. Three cases of impeller have been designed according to the variation of section configuration and tip shape. The model tests have been carried out at different speed of revolution to find out the scale effect (Reynolds number effect). The designed rake impeller was the best among them in the efficiency point of view especially at high Tip Speed Ratio (TSR). The present study is expected to be extended to conduct at high reynolds number as well as the computational study for the validation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.5
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• pp.53-59
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• 2007

Now, the study is activity that the energy market depending on a fossil fuel tend to change different way. In middle of the study compositive use of renewable energy(fuel cell and wind power, solar cell, etc.) is dispersion power system which concern is increasing. But in the case of generation of electric wind power system is changeable to be turbulence and wind and win speed are changeable in several seconds, so making the best of wind energy the MPPT that role in this case is important. In this paper suggest a MPPT which is making a use of information of wind speed and turning speed, windmill, electric power but it is simpler than former way. We could verify that a proposed controller working at the highest point of electric power when wind speed is regular speed and changable speed through the simulation.

• Environmental and Resource Economics Review
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• v.27 no.4
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• pp.695-723
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• 2018

Recently, extreme weather due to climate change has become more frequent, and increase of fine dust has worsen air quality in Korea. Therefore, not only negative perception on coal-fired power generation is dominant, but also the social acceptance of nuclear power generation declines. This study aims at deriving consumer preferences on the mid and long term power mix with various energy sources. Willingness to pay for each generation source was estimated and the preference heterogeneity of consumers was examined by using mixed logit and latent class models. Mixed logit estimation results show that the preference heterogeneity of consumers is especially large for the nuclear power relative to renewable or coal energy. According to the estimation results from the latent class model, group 1 prefers renewable energy while group 2 prefers coal energy. Group 3 shows lexicographic preference which means restricted rationality. As for the policy implication, it is necessary to understand the preference heterogeneity of consumer groups in planning the mid to long term power mix.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.28-30
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• 2009

이종접합태양전지에서 p a-Si:H/c-Si의 p a-Si:H의 증착 조건인 $H_2/SiH_4$ 비율, $B_2H_6$의 농도를 변화 시키며 실험하여 이 따라 계면 특성 변화를 연구하였다. pa-Si:H의 $H_2/SiH_4$ 비율이 상승할수록 carrier lifetime이 증가하다 다시 감소하는 경향을 나타내었다. 이는 $H_2/SiH_4$의 비율 중 효과적으로 웨이퍼표면을 효과적으로 passivation하는 지점이 있는 것으로 보인다. $B_2H_6$의 농도는 상승할수록 carrier lifetime이 줄어드는 경향을 보였다. $B_2H_6$에서 농도가 올라감에 웨이퍼 표면의 defect로 작용했을 것으로 생각된다. 이에서 몇몇의 조건으로 태양전지를 제작한 결과 $H_2/SiH_4$ 비율에 따라서는 carrier lifetime은 효율에 그 영향이 미미한 것으로 조사되었고, $B_2H_6$의 농도가 낮을수록 개방전압은 상승하는 결과를 얻어 도핑 농도가 효율에 직접적인 형향을 주는 것으로 나타났다.

• New & Renewable Energy
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• v.5 no.2
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• pp.15-24
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• 2009

As new small scale LFG (landfill gas) energy project model which can improve economic feasibility limited due to the economy of scale, LFG-Microturbine combined heat and power system with $CO_2$ fertilization into greenhouses was proposed and investigated including basic design process prior to the system installation at Gwang-ju metro sanitary landfill. The system features $CH_4$ enrichment for stable microturbine operation, reduction of compressor power consumption and low CO emission, and $CO_2$ supplement into greenhouse for enhancement plant growth. From many other researches, high $CO_2$ concentration was found to enhance $CO_2$ assimilation (also known as photosynthesis reaction) which converts $CO_2$ and $H_2O$ to sugar using light energy. For small scale landfills which produce LFG under $3\;m^3$/min, among currently available prime movers, microturbine is the most suitable power generation system and its low electric efficiency can be improved with heat recovery. Besides, since its exhaust gas contains very low level of harmful contaminants to plant growth such as NOx, CO and SOx, microturbine exhaust gas is a suitable and economically advantageous $CO_2$ source for $CO_2$ fertilization in greenhouse. The LFG-Microturbine combined heat and power generation system with $CO_2$ fertilization into greenhouse gas to enhance plant growth is technologically and economically feasible and improves economical feasibility compared to other small scale LFG energy project model.

• New & Renewable Energy
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• v.18 no.4
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• pp.38-53
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• 2022

T Recently, the government has been promoting the expansion and supply of renewable energy as an alternative for achieving carbon neutrality and the nationally determined contributions by 2030. In 2020, the Ministries of Industry and Environment and the Korea Forest Service collaborated to build a nationwide onshore wind energy siting atlas considering wind resources and forestry and environmental regulations focused on central regulations. In this study, the ordinances of the local governments were analyzed to examine the effects of regional location regulations on the expansion of onshore wind power energy generation facilities, in addition to those of central regulations. A development permit standard survey of 226 urban plan ordinances of the local governments nationwide showed that presently in 2022, 52 municipalities are applying regulations on wind energy generation facilities by ordinances. This is twice more than that in 2018, when renewable energy power generation facility development was difficult. Additionally, the location regulations applied by these ordinances were organized by items and regions, and regulatory characteristics, such as the number and scope, were analyzed by regions. To analyze the spatial distribution characteristics, JeollaNamdo was selected as the case area. A spatial DB was established for regulated areas based on the regional and central regulations, and the spatial distribution characteristics and the regulatory scope were compared and analyzed.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.1
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• pp.71-78
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• 2020

In the case of power generation using renewable energy, power production may not be smooth due to the influence of the weather. The energy storage system (ESS) is used to increase the efficiency of solar and wind power generation. ESS has been continuously fired due to a lack of battery protection systems, operation management, and control system, or careless installation, leading to very big casualties and economic losses. ESS stability and battery protection system operation management technology is indispensable. In this paper, we present a battery level calculation algorithm and a failure prediction algorithm for ESS optimization and stable operation. The proposed algorithm calculates the correct battery level by accumulating the current amount in real-time when the battery is charged and discharged, and calculates the battery failure by using the voltage imbalance between battery cells. The proposed algorithms can predict the exact battery level and failure required to operate the ESS optimally. Therefore, accurate status information on ESS battery can be measured and reliably monitored to prevent large accidents.