• Progress in Superconductivity
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• v.8 no.1
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• pp.122-126
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• 2006

This paper presents experimental and numerical investigation on heat generation of a bulk HTS for application to a 100 kWh Superconductor Flywheel Energy Storage System(SFES) bearing. An experimental device is manufactured to reproduce varying magnetic field conditions that a bulk HTS may experience during the operation of the 100 kWh SFES. The bulk HTS is directly cooled by a cryocooler while the heat is generated by the eddy currents created by varying magnetic fields induced by a coil. In order to design the cryocooling system for the 100 kWh SFES project, a preliminary experiment to investigate the actual cooling load variation under AC magnetic field has been carried out. In the experiment, two different copper holders were designed and tested. Several temperature sensors were installed on each component of the assembly and the temperatures were measured for several operating conditions of the 100 kWh SFES. The experimental investigation on the thermal response of the bulk HTS and its holder is considered to be a valuable step fur the successful materialization of a large-scale SFES.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.829-830
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• 2009

• Progress in Superconductivity
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• v.14 no.1
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• pp.60-65
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• 2012

A superconductor flywheel energy storage system (SFES) is an electro-mechanical battery which transforms electrical energy into mechanical energy for storage, and vice versa. A 35 kWh class SFES module was designed and constructed as part of a 100kWh/1MW class SFES composed of three 35 kWh class SFES modules. The 35 kWh class SFES is composed of a main frame, superconductor bearings, a composite flywheel, a motor/generator, electro-magnetic bearings, and a permanent magnet bearing. The high energy density composite flywheel is levitated by the permanent magnet bearing and superconductor bearings, while being spun by the motor/generator, and the electro-magnetic bearings are activated while passing through the critical speeds. Each of the main components was designed to provide maximum performance within a space-limited compact frame. The 35 kWh class SFES is designed to store 35 kWh, with a 350 kW charge/discharge capacity, in the 8,000 ~ 12,000 rpm operational speed range.

• 한국초전도학회:학술대회논문집
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• v.16
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• pp.88-88
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• 2006

• 한국초전도학회:학술대회논문집
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• 2007.07a
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• pp.65-65
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• 2007

• Membrane Journal
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• v.29 no.6
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• pp.314-322
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• 2019

A worsened drought in Chungnam province of Korea due to climate change and increasing water demand at Daesan industrial complex have motivated the 100,000 ㎥/d seawater desalination project. In this study, therefore, the comprehensive analysis of parameters affecting the reverse osmosis (RO) performance was conducted. Under the various conditions of feedwater salinity and temperature in Daesan, energy consumption was calculated as 2.39 ± 0.13 kWh/㎥. The decrease in membrane flux and recovery rate positively impacted annual operation cost. The average total dissolved solids (TDS) of the permeate and energy consumption with highly permeable membrane according to the membrane manufacturer were 3.84 mg/L and 2.22 ± 0.13 kWh/㎥, respectively. In addition, energy saving up to 0.29 kWh/㎥ or cost reduction of membrane module up to 15.6% is expected by changing the RO configuration from full two pass to partial or split partial two pass.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1101-1102
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• 2010

• Current Photovoltaic Research
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• v.11 no.4
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• pp.134-143
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• 2023

Efforts are being made to respond to global warming. Interest in and demand for the private sector-led RE100 campaign is also increasing. Self-built solar power generation, one of the implementation tools for RE100, is not expanding. However, it can be an economical means of implementation in the long run. In this study, we intend to analyze the impact on the optimal ratio of self-solar power generation using HOMER simulation. OPR defines the optimal solar power generation ratio and looks into what changes there are in the optimal solar power ratio when self-power consumption increases and external power purchase price changes. As a result, the optimal rate of self-solar power generation has a low impact even if self-power consumption increases. As the external power unit price increases, the optimal ratio increases, and at a power unit price of 100 KRW/kWh, OPR is 24%; at 200 KRW/kWh OPR is 31%; and at 300 KRW/kWh OPR is 34%. This shows that the electricity price replaced during the life cycle has a high impact on the economic feasibility of solar power generation. However, when the external power unit price reached a certain level, the increase in OPR decreased. This shows that it is difficult for domestic companies to achieve RE100 based on the economic feasibility of solar energy alone. Therefore, efforts are needed to supply renewable energy in the public sector.

• 전기의세계
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• v.37 no.5
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• pp.3-8
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• 1988

우리나라의 전력 사업은 1887년 경복궁내 건청궁에서 하나의 전등이 최초로 점화된 이후 100년이 경과하여 1988년 금년은 한국 전기의 2세기를 맞이하는 첫해가 되고 있다. 현재 한국이 보유하고 있는 전력생산 설비는 민간기업이 소유한 자가용 발전시설을 제외하고 총 1900만 kW에 달하고 있으며, 1987년도의 총 발전량은 785kWh에 이르러 전력수요성장은 전년도 대비 14%의 증가를 나타내고 있다. 특히, 이러한 전력 수요에 부응하기 위한 총 발전량의 53.1%의 393억kWh는 원자력 발전소에서 공급되었다는 사실은 경제성장과 사회문화의 발전에 따라 에너지 특히, 전력에너지의 역할이 더욱 중요해지고 있다는 점을 감안한다면 이미 원자력발전은 우리 경제 사회활동과 생활여건에 크게 영향을 미치고 있다는 현실로 인식할 필요가 있다.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.329-329
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• 2011

We measured thin films thickness sputtered from Cu target in the magnetron sputter system. Thin films thickness is thin as integration power in target is large. Cu thin films thickness in 100 kWh integration watt was decreased by 20% when that of beginning was compared. But the shape of thin films thickness distribution was same. For the calculation of thin films thickness distribution in the 100 kWh, the angular distribution data sputtered of Cu particles is necessary when Ar ions enter to inclined erosion surface of Cu target. We used the relation results of sputter yield and main angular distribution of sputtering particles emitted from Cu target published by G. Betz.