• KIEE International Transactions on Power Engineering
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• v.5A no.3
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• pp.214-220
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• 2005

In order to improve energy efficiency and solve power disturbances, power components measurement for both the supply and demand side of a power system must be implemented before appropriate action on the power problems can be taken. This paper presents a DSP (Digital Signal Processor)-based multi-channel (voltage 8-channel and current 10-channel) power measurement system that can simultaneously measure and analyze power components for both supply and demand. Voltage 8-channel and current 10-channel measurement is made through voltage and current sensors connected to the developed system, and power components such as reactive power, power factor and harmonics are calculated and measured by the DSP. The measured data are stored in a personal computer (PC) and a commercial program is then used for measurement data analysis and display. After voltage and current measurement accuracy revision using YOKOGAWA 2558, the developed system was tested using a programmable ac power source. The test results showed the accuracy of the developed system to be about 0.3 percent. Also, a simultaneous measurement field test of the developed system was implemented by application to the supply and demand side of the three-phase power system.

• Journal of Electrical Engineering and Technology
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• v.12 no.1
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• pp.451-458
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• 2017

An Electric Vehicle (EV) is operated with the electric energy of a battery in place of conventional fossil fuels. Thus, a suitable charging infrastructure must be provided to expand the use of electric vehicles. Because the battery of an EV must be charged to operate the EV, expanding the number of EVs will have a significant influence on the power supply and demand. Therefore, to maintain the balance of power supply and demand, it is important to be able to predict the numbers of charging EVs and monitor the events that occur in the distribution system. In this paper, we predict the hourly charging rate of electric vehicles using transformation matrix, which can describe all behaviors such as resting, charging, and driving of the EVs. Simulation with transformation matrix in a specific region provides statistical results using the Monte-Carlo Method.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.7
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• pp.1232-1236
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• 2010

In this Paper, optimal capacity of energy storage and amount of $CO_2$ reduction in Jeju is calculated. Based on electricity demand data of Je-Ju from 2006 to 2007, the estimation electricity demand from 2009 to 2018 is performed. To calculate the amount of maximum $CO_2$ reduction and energy storage capacity in Jeju, the 4th power supply planning and IPCC guideline are used. Finally, Optimal capacity of energy storage and the amount of $CO_2$ reduction are showed.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.04a
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• pp.175-180
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• 2009

According to an increasing demand of political support and development on renewable energy as a solution for the energy problem in Korea, the government has established a goal to raise renewable energy supply from 2.27% to 5% until 2011. Especially in the case of public building in which energy use is in great demand, it would bring a great advantage to develop and utilize the Photovoltaic System as an electric energy and Geothermal Heat Pump System as a thermal energy. On the occasion of Photovoltaic System, Photovoltaic module can be used as an architectural material so that it can reduce construction cost and when we use solar energy, it is possible to make building's own power supply. As for Geothermal Heat Pump System, It can be used infinitely as long as the solar energy exist and operation cost is cheap and yearly efficiency is stable. However, we need to make a plan to reduce early investment expanses for these two renewable energy systems and to expand a diffusion rate as we develop a competitive domestic technology level. So in this study, we are going to perform evaluation of economical efficiency according to the introduction of Photovoltaic System and Geothermal Heat Pump System in public buildings which will be built up inside of Daegu Sin-seo innovation city. As a first step, we will investigate present installation condition of these two renewable energy systems and based upon that, will seek efficient introduction program of renewal energy systems that can be applied in public buildings.

• Nuclear Engineering and Technology
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• v.56 no.8
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• pp.3369-3377
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• 2024

As the realization of carbon neutrality has been a main assignment for coping with the global climate change, it became necessary to analyze upcoming changes in electricity mix with economic and technical viewpoints. This paper presents a newly-developed simulation model that reflects the daily intermittency of renewable energy by applying daily average power supply-demand patterns for each season. Also, the paper provides an economic analysis in the viewpoint of investment cost, annual cost and power generation cost by utilizing the calculations from the simulation model. Four scenarios are selected for the analyses, one based on the Korean Government's 2050 Carbon Neutrality Scenario and three Nuclear Power Build-up scenarios, which are newly suggested by the authors. The simulation results show that the increase of nuclear energy from 5.7% of Government's Scenario to 37.7% of the proposed Nuclear Power Build-up Scenario leads to the decrease of about 704 billion US$ in investment cost and about 181 billion US$ in annual cost; with reduction in the increase of 2050 expected generation cost from 3.1 to 1.6 times compared with the referenced 2021 average cost. Further, this study has significance in performing the economic analysis with the expected daily power supply-demand patterns in 2050.

• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.133-147
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• 1994

Wastepaper recycling has significant implications not only in providing scarce raw material input for the paper industry but in environmental concerns such as reducing solid waste disposal, energy conservation and preservation of forest resources. The objectives of this study was (1) to develop an econometric model of demand for and supply of wastepaper, (2) to forecast wastepaper consumption and price to the year 2000 applying the econometric models estimated and (3) to estimate the elasticity of variables which are included in the wastepaper supply and demand equations. In this study wastepaper was classified into three groups, old newsprint, old corrugated and mixed For each group such as demand and supply equation were estimated. The demand equations were estimated as a function of paper and paper product consumption and wholesale price index and supply equations as a function of wastepaper price, one year lagged paper and paperproduct consumption and transportation price. Applying the econometric models to forcasting results in the future consumption and supply of wastepaper projected as 11.645 million MT and 7.396 million MT in 2000, respectively. The rate of wastepaper self-supply is forcasted about 63.5% in 2000. Especially, the rate of old neswprint self-supply is predicted about 16% which means about 2.2 million MT of old newsprint should be imported from foreign countries. Lastly, some policy measures to promote wastepaper recycling rate based upon economic and physical characteristics of wastepaper and market structure are suggested.

• Journal of Environmental Impact Assessment
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• v.22 no.6
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• pp.639-648
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• 2013

Unconventional natural gas resources are now estimated to be as large as conventional resources. Unconventional natural gas has became an increasingly important source of energy in the world since the start of this century. The factors that drive natural gas demand and supply point more and more to a future in which natural gas plays greater role in the global energy mix. The expansion of using natural gas will be expected in Korea. This research aims to analyze environmental impacts of expansion of unconventional natural gas. This research was carried out for comparative analysis between global energy mix and Korea energy mix, and developed a case that reflect the changed energy mix due to the expansion of unconventional natural gas in Korea. Also this research evaluate the production of air pollutants and the cost of the damage in power generation sector. The results of this research can be summarized as that natural gas portion of future global energy mix (about 25%) is greater than Korea energy mix (about 12%). This research developed a case that replace 10% energy of power generation sector to natural gas in the 6th demand supply program, reflecting the changed energy mix due to the expansion of natural gas use. In that case, air pollutants would be reduced gradually through 2015 to 2027. In detail, carbon dioxide reduces 22 million tons and environmental damage cost reduces 4500 billion won by 2027.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.65 no.2
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• pp.94-100
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• 2016

A virtual power plant (VPP) technology is a cluster of distributed generation installations. VPP system is that integrates several types of distributed generation sources, so as to give a reliable overall power supply. Virtual power plant systems play a key role in the smart grids concept and the move towards alternative sources of energy. They ensure improved integration of the renewable energy generation into the grids and the electricity market. VPPs not only deal with the supply side, but also help manage demand and ensure reliability of grid functions through demand response (DR) and other load shifting approaches in real time. In this paper, utilizing a variety of distributed generation resources(such as emergency generator, commercial generator, energy storage device), activation scheme of the virtual power plant technology. In addition, through the analysis of the domestic electricity market, it describes a scheme that can be a virtual power plant to participate in electricity market. It attempts to derive the policy support recommendation in order to obtain the basics to the prepared in position of power generation companies for the commercialization of virtual power plant.

• Asia Pacific Journal of Business Review
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• v.3 no.1
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• pp.19-38
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• 2018

The energy intensity of Nepal is economically not worthy, lacks eco-friendly and importantly not sustainable, and almost four times the average global energy intensity. Considerable efforts have been exercised to reduce the energy gap yet, it is still much to achieve. Nation priority on energy sector was envisaged with promulgation of investment friendly rules and law in hydropower and renewable technology even though, could not harness the sufficient energy. In amid of this acute energy crisis, the government launched the Nepal Energy Efficiency Programme (NEEP) with technical assistance from German International Cooperation (GIZ). Energy Efficiency (EE) practice is the most cost-effective method to reduce the supply and demand gap, reduce on greenhouse gases and pollution, and deter on import of petroleum products which finally improves on trade imbalance. This paper had proposed a framework of energy management team to promote energy efficient technologies in residential consumer. The energy management teams study the past records of energy use pattern of consumers and suggest appropriate technology for energy saving options. The paper provides some reviews of energy efficiency initiatives undertaken by the concern regulatory body which highlights the current status. The comprehensive knowledge acquired through exploratory research is implemented in this paper to identify the various barriers that domestic consumer is experiencing towards the active participation in energy efficiency program launched by the Government of Nepal.

• Solar Energy
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• v.16 no.2
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• pp.15-37
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• 1996

Most of the world's energy demand is met by fossil fuels, mainly petroleum and natural gas. Even though their production is not keeping up with the demand, there are many options before us-solar energy in its direct and indirect forms, nuclear breeders, thermonuclear power, geothermal energy, synthetic fluid fuels, and hydrogen as energy carrier to complement the nonfossil energy sources. But, before these energy alternatives can be utilized, in most cases, it is necessary to conduct extensive research and development work. In order to solve global energy and environmental issues, it is very important to develop and install energy supply systems which utilizes natural energy. The installation of these systems brings the following merits from the viewpoints of energy saving or environmental protection-(a) the positive use of natural energy reduces fossil fuel consumption; and (b) it also prevents environmental degradation. In this paper, the types of natural energy considered is confined to the solar, wind, hydraulic, geothermal and ocean-wave energy. And, the objective of the paper is to describe the state of the art of natural energy and future utilization prospect of them.