• Journal of Climate Change Research
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• v.6 no.2
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• pp.73-85
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• 2015

With 12 environmental basic facilities (EBF) in Busan, each business place's present situation of the operation of new and renewable energy as well as the feasibility to establish additional systems of utilizing solar energy (photovoltaic power generation system [PPGS] and solar heating system [SHS]) were investigated. Currently, with the environmental basic facilities, the new and renewable energies (such as, waste heat, biogas, PPGS, SHS, and small hydro power) can produce 195 GWh per year as electric power unit. Among the energy sources, except waste heat, biogas (154 GWh/yr) appears as the highest. Next, PPGS is the second most widely used system and produces 5,560 MWh/yr at 11 business places. Through a field survey, it appears that 19 business places of total 27 places at 12 EBFs have good locational conditions and they need an introduction of PPGS. Through it, it is investigated that it would be possible to produce 5,311 MWh/yr and to reduce $2,348tCO_2/yr$. And, it is identified that SHS can be additionally introduced in only 4 EBFs. This can reduce energy cost as much as one ten million won/yr and green-house gas as much as $28tCO_2/yr$. A cost-benefic analysis shows that the use of governmental support or private investment can be the most efficient way, when PPGS and SHS are introduced in EBFs.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.590-593
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• 2009

Tidal current power system is one of ocean renewable energies that can minimize the environmental impact with many advantages compared to other energy sources. Not like others, the produced energy can be precisely predicted without weather conditions and also the operation rate is very high. To convert the current into power, the first device encountered to the incoming flow is the rotor that can transform into rotational energy. The performance of rotor can be determined by various design parameters including numbers of blade, sectional shape, diameter, and etc. The stream lines near the rotating rotor is very complex and the interference effects around the system is also difficult to predict. This paper introduces the experiment of rotor performance and also the effect of design parameter on the performance of HAT rotor by CFD.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.150.1-150.1
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• 2011

The global rise of greenhouse gas(GHG) emissions and its potentially devastating consequences require a comprehensive regulatory framework for reducing emissions, including those from the transport sector. alternative fuels and technologies have been promoted as a means for reducing the carbon intensity of the transport sector. Renewable fuel policies were historically motivated by energy security concerns, and to promoted agricultural industries. In the last decade, biofuels have also been discussed as low or net-zero carbon soures of energy for transportation. Hence, the development of biofuels has been supported by a range of policy instruments, including volumetric targets or blending mandates, tax incentives or penalties, preferential government purchasing, government funded research, development in world-wide. As one of the most powerfuel instruments, renewable fuel mandates require fuel producers to produce a pre-defined amount(or share) of biofuels and blend them with petroleum fuel. In this study, we reviewed Renewable Fuel Standard(RFS, USA), Renewable Transport Fules Obligation (RTFO, UK) as a renewable fuel mandate policy to reduce GHG. This includes not only mandate system for blending of biofuels in transport fuels, but also sustainability to use biofuels in this system.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.162.2-162.2
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• 2010

The energy storage system is considered to be one of the useful devices for energy storing and recycling. the energy storage system can save energy cost and stabilize the system voltage. This paper presents the development of two energy storage systems. One is 750V system for light rail system. the other is 1500V system for heavy rail system.

• 한국태양에너지학회:학술대회논문집
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• 2008.11a
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• pp.25-29
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• 2008

Economic assessment of solar thermal power generation systems was carried out by calculating the levelized electricity cost. Four different commercial (or near commercial) solar thermal power systems (parabolic trough system, power tower system with saturated steam, power tower system with molten salts, and dish-stilting system) were considered for assessment. The assessment also included sensitivity analysis covering the effects of system capacity, direct normal insolation, and the system efficiency.

• Journal of the Korean Solar Energy Society
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• v.40 no.5
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• pp.13-22
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• 2020

Day ahead forecast is necessary for the electricity market to stabilize the electricity penetration. Numerical weather prediction is usually employed to produce the solar irradiance as well as electric power forecast for longer than 12 hours forecast horizon. Korea Meteorological Administration operates the UM-LDAPS model to produce the 36 hours forecast of hourly total irradiance 4 times a day. This study interpolates the hourly total irradiance into 15 minute instantaneous irradiance and then compare them with observed solar irradiance at four ground stations at 1 minute resolution. Numerical weather prediction model employed here was produced at 00 UTC or 18 UTC from January to December, 2018. To compare the statistical model for the forecast horizon less than 3 hours, smart persistent model is used as a reference model. Relative root mean square error of 15 minute instantaneous irradiance are averaged over all ground stations as being 18.4% and 19.6% initialized at 18 and 00 UTC, respectively. Numerical weather prediction is better than smart persistent model at 1 hour after simulation began.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.3
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• pp.593-602
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• 2020

Recently, as research on smart farms has been actively conducted, systems for efficiently cultivating crops have been introduced and various energy systems using renewable energy such as solar, geothermal and wind power generation have been proposed to save the energy. In this paper, we propose a new and renewable energy convergence system for crops that provides energy independence and improved crop cultivation environment. First, we present LPWA-based communication node and gateway for ICT-based data collection. Then we propose an integrated monitoring server that collects energy data, crop growth data, and environmental data through a communication node and builds it as big data to perform optimal energy management that reflects the characteristics of the environment for cultivating crops. The proposed system is expected to contribute to the production of low-cost, high-quality crops through the fusion of renewable energy and smart farms.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.3
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• pp.105-112
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• 2008

Solar energy, which is one of renewable energy, would be the most useful resources that can be applied to making energy recycling villages without using fossil energy. This study analyzed energy potential on solar energy considering weather condition in three traditional villages and compared with energy consumption surveyed. A photovoltaic system having 3.0kWp capacity of unit module can generate 182.5%, 96.1% and 170.9% of the yearly mean consumption of electric power in Makhyun, Boojang, and Soso, respectively. A flat-plate solar collector having $2.64m^2$ area of unit module can generate warm water of $142{\ell}$/day, $89{\ell}$/day, and $173{\ell}$/day, respectively in three study villages. In Makhyun and Soso, photovoltaic power and warm water produced by solar energy were sufficient to supply required amount of electric power and warm water. However, both electric power and warm water produced by unit solar module were not sufficient in Boojang area, and so it is required to increase the module area by more than 50%. According to the results of this study, the appropriate combination of energy resources can be applied to rural green-village planning if the characteristic of energy potential for each local area is considered.

• Journal of Hydrogen and New Energy
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• v.19 no.5
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• pp.367-376
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• 2008

To obtain the data of the pressure loss and differential pressure at the inside of the stack that was composed of 126 cells with 7,500 cm2 electrode area, 75kW molten carbonate fuel cell system has been operated. Computational fluid dynamics was applied to estimate reactions and thermal fluid behavior inside of the stack that was adopted with internal manifold type separator. The pressure loss coefficient K showed 72.29 to 84.01 in anode and 6.34 to 8.75 in cathode at low part of cells at the inside of 75 kW MCFC stack respectively. Meanwhile, the pressure loss coefficient of the higher part of cells at the interior of the stack showed 15.36 and 56.44 in anode and cathode respectively. These results mean that there is no big total pressure difference between anode and cathode at the inner part of 75 kW MCFC stack. This result will be reflected in 250kW MCFC system design.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.4
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• pp.735-742
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• 2021

Recently, renewable energy-related power generation facilities have been surging due to the government's "Renewable Energy 3020", "Green New Deal", "2050 Carbon Neutrality" and "K-RE100" policies. Most renewable energy facilities are small and distributed, making it difficult to manage efficiently, and small distributed resources less than 1MW are having a hard time with participating in the market due to the limited sales and avoidance of trading. In particular, the intermittency of renewable energy has a significant impact on the stability of the power grid. The government is seeking to address volatility and intermittency issues through 'small distributed resource brokerage trading, and to expand the systematic resourceization and acceptability of heterogeneous large and small distributed resources. In this work, we intend to apply an AI-based power generation prediction model to a distributed resource brokerage trading system so that it can be utilized as a foundation platform for pioneering new energy business markets.