• Advances in environmental research
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• 제4권3호
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• pp.173-181
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• 2015

This article outlines a case study of water and energy savings in a typical building through a modelling process and analysis of simultaneous water-energy saving measures. Wet cooling towers are one of the most important equipments in buildings with a considerable amount of water and energy consumption. A variety of methods are provided to reduce water and energy consumption in these facilities. In this paper, thorough the modeling of a typical building, water and energy consumption are measured. Then, After application of modern methods known to be effective in saving water and energy, including the ozone treatment for cooling towers and shade installation for windows, i.e. fins and overhangs, the amount of water and energy saving are compared with the base case using the Simergy model. The annual water consumption of the building, by more than 50% reduction, has been reached to 500 cubic meters from 1024 cubic meters. The annual electric energy consumption has been decreased from 405,178 kWh to 340,944 kWh, which is about 16%. After modeling, monthly peak of electrical energy consumption of 49,428 has dropped to 40,562 kWh. The reduction of 18% in the monthly peak can largely reduce the expenses of electricity consumption at peak.

• KIEAE Journal
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• 제16권2호
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• pp.23-31
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• 2016

Purpose: Recently energy consumption is rapidly increasing due to continuous development of social evolution in various field. In this situation, there is a lot of effort to reduce this energy consumption in many ways, especially in building energy. Preceding studies already started to analyze the housing area such as zero energy house and passive house by researching annual building energy consumption, but to apply the results of housing to office building is insufficient since it has different consumption tendency. Method: In this study, eQuest program was used for simulation and the base model is selected among standard office building in ASHRAE 90.1. Variables are divided into passive and active factors for comparison. Result: In passive factors, glazing system showed the highest energy saving rate by 21.3% with triple low-e glass and enhancing wall u-value showed the lowest energy saving rate by 3.6% with 0.15 m2/K. In active factors, VAV system showed 30.9% energy saving rate when compared to CAV system, and heat exchanger showed 10.2% energy saving rate. For regeneration energy part, photovoltaic panel generated 10.4% of base annual energy usage.

• 한국환경교육학회지:환경교육
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• 제19권3호
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• pp.102-113
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• 2006

The purpose of this study is to devise proper plans for sustainable energy management in schools through applying school eco-audit to energy field. This study is performed by literature review and the analysis of case study. This study analyzes the energy-saving model school according to the three cores of eco-audit such as school administration system, teaching-learning method, and ecological policy, and the result of the study is as followings. First, according to the analysis of school administration system for energy education programs, the participation of all the school staff is very low, and the democratic decision-making system is unsatisfactory. Second, according to the analysis of teaching-learning method, the program is mainly managed by teacher-oriented method not by learner-oriented one. The effect on the education of energy-saving program is a little improved in cognitive area, but is insufficient in affective area. Third, in the aspect of the ecological policy, the practical energy-saving effect in schools is unsatisfactory, and shows the difficulty of continuing application of the program. Consequently, it is desirable to integrate the energy-saving program with the eco-audit for sustainable energy management in schools. Implementation of the energy eco-audit in schools for the sustainable development education as teaching-learning method could achieve extended effect for the earth environmental conservation.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.600-603
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• 2005

U.S. National Research Council proposed benefits framework for energy R&D project as economic benefits, environmental benefits, security benefits and knowledge benefits. Following this framework, U.S. National Renewable Energy Laboratory evaluated the projected benefits of Federal Energy Efficiency and Renewable Energy Programs in the indicators of energy-expenditure savings, energy system cost savings, $CO_2$ emissions reductions. oil savings, natural gas saving and avoided additions to central conventional power. As this result, geothermal energy have predominant position in the energy-expenditure savings, natural gas saving and avoided addi t ions to central conventional power to FY2050. The projected benefits, in monetary value, of the whole supply-potential of geothermal energy in Korea were evaluated as 480.2 billion Won, 43.1 billion Won and 135.8 billion Won for the private energy-cost savings, social environmental-cost savings, and import energy-cost saving, respectively.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.831-835
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• 2007

Energy Saving is one of worldwide emerging issues. These days, applicable techniques of railway vehicle's regenerative energy are investigating in worldwide railway industries. Energy saving methods are "Downsizing energy loss" and "Re-utilizing kinetic energy". Useful plans for Downsizing energy loss are "adjusting operation table" and "optimizing running pattern". Furthermore, regenerative energy that is produced with decreasing speed and stoping, is an important element with reducing vehicle's weight, raising equipment 's efficiency, decreasing running resistance and re-configurating running pattern. Sustainable energy storage mass : Flywheel, EDLC(electrical double layer capacitor) and Secondary battery are applied in overseas, but these cases are not reported within the country. This research is reported for problems and economical validity that comes from by installing sustainable regenerative energy storage system in korean railway industries.

• 전자공학회논문지
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• 제51권5호
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• pp.76-87
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• 2014

오늘날 ICT 네트워크에서 에너지 소모는 전체 에너지 소모의 10% 내외로, 가까운 미래에 에너지가 현저하게 증가 할 것으로 예측되고 있다. 본 논문에서는 네트워크 품질을 보장하면서 에너지 절감이 가능한 방법을 검토한다. IP 네트워크에서 처리하는 총 트래픽 량이 일정 값 이하가 될 때, 네트워크 내의 특정 링크를 sleep 상태로 하여, 링크 양단의 NIC(Network Interface Card)에서 소모되는 에너지를 절감시키는 방안이다. 본 논문에서는 sleep 상태로 둘 링크를 최대한 도출하고, 이로 인한 노드의 경로(SPT: Shortest Path Tree)변경이 최소화되도록 한다. 우선 target 링크를 선정하고, 선정된 target 링크가 sleep 상태로 두는 것이 가능한지를 위임/수탁 라우터 기반의 heuristic 라우팅 방안에 의해 결정하는 방법을 제안한다. 위임/수탁 라우터 기반의 heuristic 라우팅 방안에서, 시뮬레이션을 통해 min_used traffic 및 min_path의 입력 유형의 특성을 평가한다. Min_used traffic 입력을 이용한 heuristic 방식이 min_path 입력 방식에 비해 링크 절약 효율은 대체적으로 5% 정도 우수하지만, 각 노드의 SPT의 길이는 반대로 평균 약 0.2홉 정도 증가하고 있다. 그러나 이 두 방식은 random 입력 방식에 비해 링크 절약 효율과 SPT 경로 감소 면에서 상당히 우수하다. 또한 본 알고리즘 수행 중 링크 freezing 방법에 따라 링크 절약 효율이 최대 80% 정도 향상되므로 에너지 절감 효과가 크다. 따라서 본 논문에서 위임/수탁 라우터 기반의 heuristic 라우팅 방안을 적용하여 네트워크 품질 유지하면서 에너지를 절약 할 수 있음을 확인 한다.

• 전기학회논문지
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• 제67권11호
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• pp.1477-1485
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• 2018

There are two major issues for activated sludge process in sewage treatment plant. One is how to make sewage be more clean and the other is the energy saving in sewage treatment process. The major monitoring sewage qualities are chemical oxygen demand, phosphorus, nitrogen, suspended solid in effluent. These are transmitted to the national TMS(Telemetry Monitoring System) at every hour. If these exceed the environmental standard, the environmental charges imposed. So, these water qualities are to be controlled below the environmental standard in operation of sewage treatment plant. And recently, the energy saving is also important in process operation. Over 50% energy is consumed in blowers and motors for injection oxygen into aeration tank. So, with the water qualities to be controlled below the environmental standard, the energy saving also is to be accomplished for efficient plant management. Almost researches are aimed to control water quality without considering energy saving. AI techniques have been used for control water quality. AI modeling simulator provided the optimal control inputs(blower speed, waste sludge, return sludge) for control water quality. Blower speed is the main control input for activated sludge process. To make sewage be more clean, the excessive blower speed is supplied, but water quality is not better than the previous. In results, non necessary energy is consumed. In this paper we propose a new method that the energy saving also is to be accomplished with the water qualities to be controlled below the environmental standard for efficient plant management. Water qualities in only aeration tank are used the inputs of fuzzy models. Outputs of these models are chemical oxygen demand, phosphorus, nitrogen, suspended solid in effluent and have the environmental standards. In test, we found this method could save 10% energy than the previous methods.

• 한국항해항만학회지
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• 제39권2호
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• pp.107-113
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• 2015

This paper analyzes and evaluates the importance of energy saving measures based on qualitative survey. Through literature review and group interviews with specialists, 4 factors, 13 measures for energy savings, and 4 evaluation criteria were selected to carry out an Analytic Hierarchy Process (AHP) analysis. At the first stage of AHP analysis, the importance of factors was derived, and then the importance of 13 measures. Lastly, the cross examination of 4 factors was carried out in order to evaluate the best possible qualitative considerations. The result revealed that 'choosing the best course weather', is the most important factor with the highest value on applicability and operational complexity criteria. These results may imply that operational considerations are regarded as a main factor to be taken into account when considering appropriate energy saving measures.

• KIEAE Journal
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• 제13권2호
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• pp.53-60
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• 2013

This study examined the building envelope structure used in small housings near urban area which have not good energy source in relation to the application of passive design for energy saving of small-sized architectural design firms in local cities and aimed to provide the basic materials of future design direction of designers and housing owners by analyzing economy of a project in order to know the amount of energy saving and additional expenses depending on the building envelope pattern. As a result of comparing and examining the energy saving cost from the period of use compared to investment by the thickness of insulating materials based on building envelope pattern for energy saving, it was found that the thicker the insulating materials are, the more energy saving amount is. While the current bead-type insulating materials have short payback period due to low initial investment, extruded insulating materials show the difference of five years compared to bead-type insulation because of its high initial investment.

• 자원ㆍ환경경제연구
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• 제16권3호
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• pp.485-510
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• 2007

본 연구에서는 우리나라 제조업의 전체 에너지절약 투자액과 에너지원단위 자료를 이용하여 에너지절약 투자액이 에너지원단위를 개선시키는 효과가 있는지를 실증분석하였다. 실증분석에 사용된 자료는 패널자료(panel data)로서 제조업 9개 업종 가운데 분석기간 동안 시계열의 안정성이 상대적으로 떨어지는 것으로 판단되는 기타 제조업을 제외한 8개 업종이다. 이 가운데 에너지 다소비업종과 비다소비업종은 각각 4개씩이다. 분석기간은 에너지절약 설비 투자 자료가 이용 가능한 1982~2004년까지이다. 추정결과에 의하면, 첫째로 에너지절약 투자는 에너지원단위를 개선시키는 효과가 있는 것으로 추정되었으나, 에너지절약 절대량 측면에서 그 효과는 그리 크지 않는 것으로 나타났다. 둘째로 에너지절약 자금이 에너지원단위를 개선시키는 데 있어 탄력성 측면에서는 에너지 다소비 업종에 비해 에너지 비다소비 업종에서 더 큰 것으로 추정되었다. 셋째로 에너지절약 관련 투자에 있어 에너지절약 투자 자금도 중요하지만, 자동화 투자도 에너지원단위 개선에 중요한 역할을 하는 것으로 나타났기 때문에 투자의 효율성 개선 측면에서 신중한 접근이 필요하다. 분석에 의하면, 자동화 투자의 에너지원단위 개선효과가 탄력성 측면에서 에너지절약 투자보다 큰 것으로 나타났다. 그러나 투자규모면에서 보면, 에너지절약 투자규모는 자동화 투자 규모에 비해 현격히 낮다. 따라서 탄력성 측면에서는 에너지원단위가 에너지절약 투자액보다 자동화투자에 보다 민감하게 반응하지만, 투자규모를 고려한 단위 투자비에 대한 온실가스 배출 저감효과는 에너지절약 투자액이 보다 큰 것으로 나타났다.