• Journal of Electrical Engineering and Technology
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• v.8 no.5
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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.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.934-939
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• 2009

To promote citizen's involvement in the GHG(Green House Gas) reduction policy, Busan city administration adopted an pilot energy incentive system called 'energy mileage'. The energy mileage system was designed to make energy end-users motivated to reduce domestic electricity use by providing financial rewards. Through the course of the pilot period, 5,3330 householders volunteerly participated the pilot system. About 66% of the participants managed to make energy saving against the same period of the previous year while 38.8% achieved the targeted reduction rate(i.e. over 10%) and received the equivalent rewards.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2335-2339
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• 2013

Relative reactivity of various Al-substituted dialkylalans ($AlR_2(X)$) in reduction of acetone has been studied with density functional theory and MP2 method. Formation of the alan dimers and the alan-acetone adduct, and the transition state for the Meerwein-Ponndorf-Verley (MPV) type reduction of the adduct were calculated to figure out the energy profile. Formation of dimeric alans is highly exothermic. Both the relative free energies for acetone-alan adduct formation and the TS barriers for the MPV type reduction with respect to alan dimers and acetone were calculated and they show the same trend. Based on these energetic data, relative reactivity of alans is expected to be; $AlR_2(Cl)$ > $AlR_2(OTf)$ > $AlR_2(O_2CCF_3)$ > $AlR_2(F)$ > $AlR_2(OMs)$ > $AlR_2(OAc)$ > $AlR_2(OMe)$ > $AlR_2(NMe_2)$. The energy profile is relatively well correlated with the experimental order of the reactivity of Al-substituted dialkylalans. It is noted that the substituents of alans have initial effects on the relative free energies for the carbonyl-adduct formation. Therefore, an $AlR_2(X)$ which forms a more stable carbonyl-adduct is more reactive in carbonyl reduction.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.8
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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.

• Journal of the Korean Institute of Educational Facilities
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• v.16 no.1
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• pp.43-50
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• 2009

This research is to analyze LCC of Heat Pump system in university building by reduction of electric power costs for education and incentive system for gas. Produced details item different expense of EHP and GHP equipment construction step and preservation administration step. Analysis result is as following. 1) Executed LCC analysis for target system after lowering whole curriculum reduction of electric power costs for education. Analysis result, energy cost-cutting effect of EHP appears greatly than GHP unlike existent study finding, EHP decided by economical system. 2) Sensitivity analysis executed by incentive 500,000 won per units and geometrical ration of gas expense by 1%. As a result, because lowering effect of electric charges appears greatly, EHP decided by more economical system than GHP. As research result of front is different from existent study finding, EHP by lowering of electric charges for alteration and education of governmental frequent volunteer system was decided by more economical system than GHP.

• Journal of the Korean Solar Energy Society
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• v.31 no.4
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• pp.1-8
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• 2011

In this paper, inverse building modeling was applied to building perimeter zones which have different window orientation. Two test zones of east-facing and west-facing zones in ERS(Energy Resource Station) building, which is representative of small commercial building, was used to test performance of cooling load calculation and peak cooling load reduction. The dynamic thermal load model for the east and west zone was validated using measured data for the zones and then it was used to investigate the effect of peak cooling load reduction by adjustment of indoor cooling temperature set points during on-peak time period. For the east zone, the peak load can be reduced to about 60% of the peak load for conventional control even without any precooling. For the west zone, PLR is nearly independent of the start of the on-peak period until a start time of 1pm. Furthermore, PLR has a small dependence on the precooling duration. Without any precooling, the peak cooling load can be reduced to about 35% of the peak load associated with conventional control.

• Journal of Korean Living Environment System
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• v.24 no.6
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• pp.810-823
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• 2017

The envelope is important for sustainable building. Recent commercial buildings are causing thermal degradation and cooling load due to the increase of the area of the windows. Therefore, this research studied kinetic shading system which can improve energy saving and visual environment in summer. For that, this study proposed new shading system and shape considering the orientation of the building and the location of the sun. Based on this, this study analyzed the effectiveness on energy reduction and improvement of visual environment by applying the kinetic shading system proposed in this study. As the results of this study, energy reduction rate was 35% in the east, 22.9% in the south, and 30.7% in the west depending on the application location. Also, as the result of the illuminance analysis, it was found that the effect of achieving uniformity ratio of illumination was considerable.

• Journal of Korea Technology Innovation Society
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• v.5 no.2
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• pp.152-166
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• 2002

This study analyzes effects of the government-funded energy conservation technology research program using a simple calculation-based valuation method. Energy conservation amounts by 50 commercialized technologies are calculated and then transformed to energy conservation effect and pollution reduction effect. Export and import-substitution effects are also calculated. Empirical results show that effectiveness of the research program has been increasing rapidly after 1996 while research fund has not. We suggest rapid increase of government support of this program so that the goal of the research program can be reached.

• Journal of the Korean Applied Science and Technology
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• v.30 no.3
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• pp.480-487
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• 2013

Bioenergy is classified to one of the renewable energy resources such as solar, wind, hydro and tidal energies. It should be noted that all the renewable energies contribute to the reduction of greenhouse gases emission. In some cases, energy from wastes was also categorized as a renewable energy in our country even though it has only negligible effect on the emission reduction. In this paper, we tried to identify the bioenergy in order to follow the global indices of the renewable energy. The indices evaluated here were whether a resource is renewable, biogenic, biodegradable, combustible and organic. Biogenic and combustible were selected as the indices to identify the bioenergy. It was also suggested that combustible as an index can be exchangeable to organic.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1594-1598
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• 2007

Energy saving is an important topic for each heavy user of the power system, including railway operators. Therefore, four strategy of train operations studied that maximum speed reduction, reduced acceleration rate, anticipatory coasting, and saw-tooth coasting for energy saving. The Simulation model of the study used to investigate the performance of a railway system, and it was used to study the effect of energy saving strategies for the train operation. The Study investigate train operation strategy for energy saving, investigate the effect of strategy, and find the energy optimization of acceleration, coasting, braking section used Run-Curve simulator from train data.