• 에너지공학
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• 제18권4호
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• pp.221-229
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• 2009

본 연구에서는 지역난방 수도권 지사별 실태 및 영향인자 진단 분석을 통해 개별지사와 연계지사간의 효율적이며 경제적인 운전을 할 수 있는 최적화 운전 프로그램을 개발하고 이를 통해 실제보다 최적화 운전시 어느정도 경제적 효과가 있는지를 확인해 보고자 하였다. 이를 위해 각 지사별 실태조사를 통해 보일러, 펌프, 관련Tag(온도, 압력, 연료량)등 다양한 인자를 진단/분석하였고 최적화 프로그램 개발을 위해 방대한 1년간 데이터를 인자별 Data base를 구축할 수 있었다. 또한 이를 통해 지사별 최적화 프로그램을 개발하여 수행한 결과, 최적화 선호도는 "소각장 >한전수열 >CHP >PLBs >PLBw"이었으며 연계를 제외한 각 지사별 실제운전과 최적화 운전 비용차이가 거의 없었다. 한편, 통합운영 최적화 프로그램을 개발하여 실제와 동일한 총 생산열량과 동일한 한전수열량과 같은 고정인자는 변동치 않고 단지 연계공급/수급열량만을 프로그램을 통해 최적조건(가장 저렴하고 효율적인 열량을 우선공급하는 조건)으로 효율적으로 운전한 결과, 사계절별 임의로 선정된 2~4일에 대한 일일 절감율 2.45~6.80%, 일일 절감액 22,727천원~60,077천원을 나타내었는데, 특히 겨울철에 제일 많은 수요량을 나타내며 가장 많은 절감비용을 얻을 수 있었고 수요량이 적은 여름철이 절감비용이 가장 작았다. 이러한 결과를 토대로 1년간 실제 열량 생산비용 대비 연간 절감비용을 환산하면 이론적으로 84억원이며 이는 수도권 전지사의 연간 총 열생산 비용(3,070억원)의 2.74%이상을 절감하는 경제적 효과가 있음을 확인할 수 있었다.

• 한국조경학회지
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• 제27권2호
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• pp.19-28
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• 1999

This study quantified shading, evapotranspiration and windspeed-reduction effects of trees on use and cost of heating and cooling energy in two residential neighborhoods of Chuncheon different in tree cover. Annual savings per residence of heating energy were approximately 1,210 MJ(1%) and those of cooling energy, 130 kWh(10%) in study district 1 having tree cover of about 10% . For district 2 with tree cover of about 20%, annual heating and cooling savings were 2,130 MJ(2%) and 180 kWh(19%) per residence, respectively. Trees annually saved energy costs by approximately ￦31,000 ($26, $1=￦1,200) per residence in district 1 and by ￦49,000($41) in district 2. One tree taller than 3 m resulted in annual energy savings of ￦8,000($7) in the study districts. Energy savings by trees in district 2, which had higher tree cover by 10% difference than district 1, were about 2 times greater than those in district 1. This implies that more tree plantings could enhance energy saving effects. Of the total costs saved, 58% was attributed to windspeed reduction and 47%, evapotranspiration. However, shading increased energy costs by 5% due to tree plantings at the wrong locations. Full tree plantings on the west and north of buildings and avoidance of shade-tree plantings of use of solar-friendly trees on the south are recommended to increase building energy savings efficiently.

• 대한전기학회논문지:전력기술부문A
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• 제54권8호
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• pp.396-400
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• 2005

This paper proposes the cost analysis on the energy efficient equipment when this equipment is participated in the demand-side bidding. Conventional demand-side bidding is exercised through load re-distribution. However if this load reduction is exercised by the use of high efficient equipment, its effect will be assumed to be more economical. This paper analyses this cost-benefit effect of high efficient equipment in the demand-side bidding.

• 한국태양에너지학회 논문집
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• 제30권1호
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• pp.50-60
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• 2010

Today, the amount of energy consumption in the university campuses is huge. The effort for the energy consumption reduction in university campuses is certainly needed by the following reason; first, contribution to the greenhouse gas discharge reduction demand. Second, energy cost reduction in university campus. Third, contribution to the improvement of the social awareness as the maximum higher educational institutions. The energy consumption analysis of current situation has to be executed for the energy consumption reduction in university campus. The energy reduction possibility in which it exists in university campuses can be understood through the energy consumption analysis. And the application is possible as fundamental data of the policy establishment for the effective energy reduction in university campuses. Especially, the best way to reduce the energy consumption in university campuses that is the energy consumption reduction of buildings. Accordingly, this study derived the plans for improving the performance of energy in the university building by analyzing case study, so this study analyzed the performance of energy for the university building through VE, a program for the analysis of building energy. Based on this result, this study classified the plans improving the efficiency of energy in university building into the plan for passive control and active control respectively, and suggested some concrete plans, and finally evaluated the performance of decreasing energy consumption for each plan.

• 대한건축학회논문집:구조계
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• 제34권11호
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• pp.81-87
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• 2018

Among various types of geothermal heat pump systems, Vertical Closed-Loop Geothermal Heat Pump (VGSHP) has received increasing attention due to a variety of advantages such as the potential to be installed in a relatively small space and improved energy efficiency. In this research, the performance of VGSHP system coupled with heat storage tank was evaluated, by analyzing operational behavior of heat storage tank, the variations of heat pump energy performance due to the connection with heat storage tank, part load ratios characteristics of heat pump and the corresponding energy cost, compared to chiller and boiler based conventional system. The results of this study showed that the VGSHP system coupled with heat storage tank showed an energy saving effect of about 18% for cooling and about 73% for heating, and annual heating/cooling energy cost reduction of 43,000,000 KRW ($ 39,000), compared to the conventional air conditioning system. In addition, after considering both energy cost and initial investment cost including equipment, installation and auxiliary device expenses, payback period of approximately 11.8 years was required.

• Journal of Electrical Engineering and Technology
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• 제8권5호
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• pp.1070-1077
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• 2013

Owing to the consistent increase in energy efficiency issues, studies for improving regenerative energy utilization have been receiving attention in the Urban DC railway systems, where currently, the utilization of regenerative energy is low due to the lack of a specific plan for using this energy. The regenerative energy in railway systems has a low efficiency problem which results in the increase of the catenary voltage and a possibility to create problems to the electrical devices connected to the system. This paper deals with the power integration of large urban railway subsystems to improve regenerative energy utilization where the railway subsystems are integrated with other railway subsystems to improve the energy efficiency. Through the case studies, to find the realistic effect of integrated operation, the Seoul Metro subsystems, namely Line 5 and Line 7, has been applied. Also, evaluation for the electricity cost saving has been performed by using KEPCO electricity cost table.

• Journal of Electrical Engineering and Technology
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• 제9권6호
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• pp.1843-1850
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• 2014

In this paper, we investigate a group building based power consumption scheduling to minimize the electricity cost. We consider the demand shift to reduce the peak load and suggest the compensation function reflecting the relationship between the change of the building demand and the occupants' comfort. Using that, the electricity cost minimization problem satisfied the convexity is formulated, and the optimal power consumption scheduling algorithm is proposed based on the iterative method. Extensive simulations show that the proposed algorithm achieves the group management gain compared to the individual building operation by increasing the degree of freedom for the operation.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2009년도 학술논문요약집
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• pp.51-52
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• 2009

Recently, several industrial countries using the fission energy have given attention to the Gen-IV SFR (sodium-cooled fast reactor) for achieving sustainable nuclear energy systems. In this context, an SFR is currently developed at the design concepts study stage in the Republic of Korea [Kim & Hahn 200909]. The sustainability of systems means economic, environment-friendly, proliferation-resistant, and safer systems. More specifically, this sustainability can be accomplished in terms of resource recycling and radioactive waste reduction. In the present work, the objective of fuel cycle cost modeling is to identify the impact of various conceptual options as a cost reduction measure for the Gen-IV SFR at the design concepts study stage. It facilitates the selection of several reasonable fuel cycle pathways for the future Gen-IV SFR from an economic viewpoint.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제48권6호
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• pp.294-300
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• 1999

There is a growing interest in hybrid electric vehicles due to environmental concerns. Recent efforts are directed toward developing an improved main component systems for the hybrid electric vehicle applications. Soon after the introduction of electric starter for internal combustion engine early this century, despite being energy efficient and nonpolluting, electric vehicle lost the battle completly to internal combustion engine due to its limited range and inferior performance. Hybrid Electric vehicles offer the most promising solutions to reduce the emission of vehicles. This paper describes a method for cost reduction estimation of parallel hybrid electric vehicle. We used a cost reduction structure that consisted of five major subsystems (three-type and two-type motor) for parallel hybrid electric vehicle. Especially, we estimated the potential for cost reductions in parallel hybrid electric vehicle as a function of time using the learning curve. Also, we estimated the potentials of cost by depreciation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.420-421
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• 2006

The cost-effective reduction of greenhouse gas(GHG) emission to avert the most severe impacts of climate change remains one of the widely accepted priorities for global action. In order to facilitate cost-effective abatement strategies, the Kyoto Protocol introduced three mechanisms, or flexible instruments, the Emissions Trading(ET), the Joint Implementation(JI) and the Clean Development Mechanism(CDM). The CDM enables Annex I countries to the Kyoto Protocol to partially meet cost-effectively their emission reduction commitments by undertaking GHG mitigation Projects in developing countries, which do not have any GHG abatement obligations and where the emission reductions are cheaper. One of the major barriers hampering the wide spread implementation of CDM is the high transaction costs associated with the initial identification of promising CDM projects. This paper presents development of a pre-validation program of CDM. The developed program may provide a useful aid to potential investors and project developers as a supportive pre-evaluation tool, and may become an effective tool for the promotion of renewable energy and fuel switching projects.